ICHEP 2020

Jul 28, 2020, 9:00 AM → Aug 6, 2020, 11:00 PM Europe/Prague

virtual conference

Rupert Leitner (Charles University (CZ)), Zdenek Dolezal (Charles University (CZ))

40th International Conference on High Energy Physics

ICHEP is a series of international conferences organized by the C11 commission of the International Union of Pure and Applied Physics (IUPAP). It has been held every two years since more than 50 years, and is the reference conference of particle physics where most relevant results are presented.

At ICHEP, physicists from around the world gather to share the latest advancements in particle physics, astrophysics/cosmology, and accelerator science and discuss plans for major future facilities.

Bulletin 1

Bulletin 2

Conference picture

Conference picture (small)

ICHEP Summary Book

Instructions for speakers and chairs

Mattermost instructions

Practical handbook

Program at glance

Sponsorship Brochure

Tuesday, July 28

Astro-particle Physics and Cosmology: Session I - Premiere

Convener: Constantinos Skordis (Institute of Physics AS CR)

Replay

1 Dark matter Annihilation in Most Luminous and the Most Massive Ultracompact Dwarf Galaxies (UCD)

We explore the potential astrophysical signatures of dark matter
(DM) annihilations in ultracompact dwarf galaxies (UCDs) considering two of the richest known galaxy clusters within 100 million light-years, nominally, Virgo and Fornax. Fornax UCD3 is the most luminous UCD and M59 UCD3 is the most massive UCD. With the detection of a 3.5 million solar mass black hole (BH) in Fornax UCD3, we carefully model several DM enhanced profiles scenarios, considering both the presence of the supermassive black hole (SMBH) and DM. For Fornax UCD3, the comparison of the stellar and dynamical masses suggests that there is little content of DM in UCDs. M59 UCD3 did not receive the same attention in simulations as Fornax UCD3, but deep radio imaging and X-ray observations were performed for M59 UCD3 and can be used to place limits in DM content of these UCDs. We work with an average estimative of dark matter content considering the Salpeter and Kroupa mass functions. We model Fornax UCD3 and M59 UCD3 to have a DM content that is the average of these mass functions. We then analyze the constraints for Fornax and M59 UCD3 coming from gamma-ray and radio sources considering in our simulations, a dark matter particle with mass between 10 − 34 GeV. In the absence of strong γ-ray signatures, we show that synchrotron emission from electrons and positrons produced by DM annihilations can be very sensitive to indirect DM search. We find that DM parameters can be significantly constrained at radio frequencies and the spike profiles play an interesting rule in order to deep study the enhancements of DM & BH interactions in ultracompact galaxies.

Speaker: Prof. Fortes Elaine (Unipampa)

Dark matter Annihilation in Most Luminousand themost massive Ultracompact Dwarf galaxies.pdf

2 Heat Engine for Black Holes in Presence of Cyclic Thermodynamics Behavior

The study of astrophysics context of massive theory leads to the black hole heat engine may be regarded as a possible energy source of the high energy astrophysical phenomena. Therefore, a black hole engine may be regarded as a possible source of power gamma rays and ultrahigh energy cosmic rays. Propose of this research was study to heat engine provided by black holes in presence of cyclic thermodynamics behavior. The main motivation was to investigate the rate of change of the cyclic process based on massive theory leads to the effect as different of the efficiency of black hole engines in massive gravity. It would be interesting to investigate the efficiency calculated on the horizon with these three different topologies were spherical flat and hyperbolic which then make a comparison. The results in this research will be shown that the highest efficiency for the heat engine belongs to black holes with the hyperbolic horizon, while the lowest one belongs to the spherical black holes.

Speaker: Dr Atirat Maksuwan (Pathumwan Institute of Technology)

3 Production of Thermal Axions across the ElectroWeak Phase Transition

If there are light axions in nature they will very probably leave a cosmic background, just like neutrinos. In this work we complete the study of thermal axion production above the QCD Phase Transition (QCDPT) by including the scatterings of the axion with the longitudinal components of the W and Z bosons. We study the predictions for pa4ticular QCD axion scenarios, like the KSVZ and the so-called Minimal Flavour Violating Axion.

Speaker: Fernando Arias Aragón (Universidad Autónoma de Madrid)

Thermal Axions across EWPT Talk.pdf

4:45 PM Coffee break

4 Generation of magnetic fields in cosmic string wakes

We describe a novel method of generating magnetic fields in cosmic string wakes from neutrino currents. We show that neutrino currents act as a cross-perturbation across the cosmic string wake. This cross perturbation along with the high Reynolds number generates a magnetic field in the wake of the cosmic string. The neutrino current is generated by the neutrinos rotating around the Abelian Higgs strings. As the string moves through the cosmic plasma, the velocity kick generated by the motion of the string will enhance the neutrino current in the wake region. The neutrino current density depends on its distance from the string and is oscillatory in nature. This leads to neutrino density gradients in the plasma. We have shown that these neutrino gradients give rise to electron gradients in the plasma, which in turn generate magnetic fields of the order of $10^{13}$ Gauss.

Speaker: Sovan Sau (University of Hyderabad)

ICHEP.pdf

sau2020.pdf

5 On the Abraham-Minkowski controversy: Can the time delay of the gamma-ray bursts travelling through interstellar space be explained without invoking the Lorentz-invariance violation?

The ANTARES neutrino telescope and other experiments are searching for more detailed information on the previously observed shifted high-energy neutrinos from the gamma-ray bursts travelling through interstellar space. Many theoretical models have been proposed to explain this phenomenon, based on assuming the Lorentz-invariance violation. In this talk I shall show that the dispersion phenomenon of gamma-ray in an interstellar space considered as a cosmic plasma can explain this effect. This in turn indicates that invoking the drastic assumption of Lorentz-invariance violation for such a problem can be premature.

Speaker: Prof. Masud Chaichian (University of Helsinki)

Chaichian_AM_dilemma_ICHEP2020.pdf

6 New Properties of primary and secondary cosmic rays measured by AMS

We present precision high statistics measurements of primary cosmic rays protons, Helium, Carbon and Oxygen and the secondary cosmic rays Lithium, Beryllium and Boron measured by Alpha Magnetic Spectrometer on ISS in the rigidity range from 2 GV to 3 TV.
These measurements are based on more than one billion nuclei collected by AMS during first 7 years of operation from May 2011 to May 2018. The unexpected properties of these cosmic rays as well as high statistics secondary-to-primary flux ratios such as Li/C,Be/C, B/C, Li/O, Be/O and B/O will be discussed.

Speaker: Dr Mercedes Paniccia (Universite de Geneve (CH))

ICHEP2020 - New Properties of Primary and Secondary Cosmic-Rays measured by AMS - M.Paniccia.pdf

6:30 PM Coffee break

7 New Properties of Neon, Magnesium, Silicon, and Sulfur Primary Cosmic Rays observed by the Alpha Magnetic Spectrometer on the International Space Station

Neon, Magnesium, Silicon, and Sulfur nuclei in cosmic rays are thought to be mainly of primary origin, they are mainly produced and accelerated in astrophysical sources. We report the latest precise measurements of the Ne, Mg, Si, and S individual spectra in the rigidity range from 2 GV to 3 TV by the Alpha Magnetic Spectrometer based on the data collected during its first 7 years of operation. Unexpectedly, compared with the spectra of light nuclei Helium, Carbon, and Oxygen, the spectra of heavy nuclei Ne, Mg, Si, and S show distinctly different new properties.

Speaker: Qi Yan (Massachusetts Inst. of Technology (US))

2020ICHEP_AMSHZNuclei_QiYan.pdf

8 Anisotropy of Elementary Particle Fluxes in Primary Cosmic Rays Measured with the Alpha Magnetic Spectrometer on the ISS

Analysis of anisotropy of the arrival directions of galactic protons, electrons and positrons has been performed with the Alpha Magnetic Spectrometer on the International Space Station. These results allow to differentiate between point-like and diffuse sources of cosmic rays for the explanation of the observed excess of high energy positrons. The AMS results on the dipole anisotropy are presented along with the discussion of implications of these measurements.

Speaker: Miguel Angel Velasco Frutos (Centro de Investigaciones Energéti cas Medioambientales y Tecno)

MAVelasco_ICHEP2020.pdf

9 Precision Measurement of the Monthly Boron, Carbon and Oxygen Fluxes in Cosmic Rays with the Alpha Magnetic Spectrometer on the International Space Station

Cosmic Rays (CR) inside the Heliosphere are subject to the effects of the Solar Modulation, resulting from their interaction with the solar wind and with the interplanetary magnetic field. These effects are strongly related to the solar activity and lead to a temporal variation of the cosmic ray intensity near Earth for rigidities up to few tens of GV. Previous AMS results on proton and helium spectra showed how the two fluxes behave differently in time. To better understand these unexpected results, one should therefore study the next most abundant species such as carbon, oxygen, and boron.
In this contribution, the precision measurements of the monthly boron, carbon and oxygen fluxes for the period from May 2011 to May 2018 with Alpha Magnetic Spectrometer on the International Space Station are presented. This period covers the ascending phase of solar cycle 24 together with the reversal of the Sun’s magnetic field polarity through the maximum. The detailed temporal variations of the boron, carbon and oxygen fluxes are shown up to rigidities of 60 GV. The time dependence of the B/C, B/O and C/O fluxes ratios are also presented.

Speaker: Jian Tian (Universita e INFN, Perugia (IT))

ICHEP2020_BCO.pdf

8:15 PM Coffee break

8:25 PM General discussion

Beyond the Standard Model: Session I - Premiere

Conveners: Alexandre Sousa (University of Cincinnati), Mia Tosi (Università degli Studi di Padova & INFN)

Replay

10 R-parity violating SUSY searches in ATLAS

R-parity violating (RPV) SUSY models evade the stringent limits from missing-energy-based searches, and remain excellent candidates for low-scale SUSY. ATLAS has completed several dedicated searches for RPV signatures in Run 2, the most recent of which will be shown in this talk.

Speaker: Johannes Josef Junggeburth (Max-Planck-Institut fur Physik (DE))

mpi-beamer-template.pdf

11 New bounds on sneutrino masses through collider searches

Though collider searches are constraining supersymmetric parameter space, generic model independent bounds on sneutrinos remain very low. We calculate new model independent lower bounds on general supersymmetric scenarios with sneutrino LSP and NLSPs. By recasting ATLAS LHC exotic searches in mono boson channels, we place an upper bound on the cross section on $pp \rightarrow \tilde{\nu} \tilde{\nu} + V $ processes in mono-photon, mono-$Z$ and mono-Higgs channels. We also evaluate the LHC discovery potential of sneutrinos in the HL-LHC 3 inverse attobarn run.

Speaker: Humberto Gilmer (Ohio State University)

ICHEP_2020-Gilmer.pdf

12 Higgs properties: constraints and sensitivity on Supersymmetry?

We present some highlights on the complementarity of the Higgs and SUSY searches at the LHC, using the 8 and 13 TeV results. In particular, we discuss the constraints that can be obtained on the MSSM parameters by the determination of the Higgs boson mass and couplings. In addition, we investigate the interplay with heavy Higgs searches, and evaluate how higher LHC luminosities and a future linear collider can help probing the pMSSM Higgs sector and reconstructing the underlying parameters.

Speaker: Nazila Mahmoudi (Universite Claude Bernard Lyon I (FR))

ICHEP_July2020_Nazila.pdf

13 Sbottoms as probes to MSSM with nonholomorphic soft interactions

Presence of non-holomorphic soft SUSY breaking terms is known to be a possibility in the popular setup of the Minimal Supersymmetric Standard Model (MSSM). It has been shown that such a scenario known as Non-Holomorphic Supersymmetric Standard Model (NHSSM) could remain ‘natural’ (i.e., not fine-tuned) even in the presence of a rather heavy higgsino-like LSP. In a first study of such a scenario at colliders (LHC), we explore a possible way that focuses on the sbottom phenomenology. This exploits the usual tanβ-dependence (enhancement) of the bottom Yukawa coupling but reinforced/altered in the presence of non-vanishing nonholomorphic soft trilinear parameter A'_b. For a given set of masses of the sbottom(s) and the light electroweakinos (LSP, lighter chargino etc.) which are known from experiments, the NHSSM could manifest itself via event rate in the 2b + MET final state, which could be characteristically different from its MSSM expectation. Impact on the phenomenology of the stops at the LHC is also touched upon.

Speaker: Ms Samadrita Mukherjee (Indian Association for the Cultivation of Science)

Samadrita_ICHEP2020Sbottom.pdf

14 Beyond the Standard Model Physics Prospects at Deep Underground Neutrino Experiment

The Deep Underground Neutrino Experiment (DUNE) is an international project for neutrino physics and proton-decay searches, currently in the design and planning stages. Once built, DUNE will consist of two detectors exposed to the world’s most intense neutrino beam. The near detector will record neutrino interactions near the beginning of the beamline, at Fermilab. The other, much larger, detector, comprising four 10-kton liquid argon time projection chambers (TPCs), will be installed at a depth of 1.5 km at the Sanford Underground Research Facility in South Dakota, about 1300 km away from the neutrino source.
The unique combination of the high-intensity neutrino beam with DUNE's high-resolution near detector system and massive LArTPC far detector enables a variety of probes of BSM physics, either novel or with unprecedented sensitivity, from the potential discovery of new particles (sterile neutrinos or dark matter), to precision tests of beyond the three-flavor mixing paradigm, Non-standard Neutrino Interactions, Heavy Neutral Leptons, or the detailed study of rare processes (e.g. neutrino trident production). The talk will review these physics topics and discuss the prospects for their discovery at the DUNE experiment.

Speaker: Doojin Kim (University of Florida)

Presentation_ICHEP2020_DoojinKim.pdf

15 Search for Proton Decay via $p\to e^+\pi^0$ and $p\to \mu^+\pi^0$ in 450 kiloton$\cdot$years Exposure of the Super-Kamiokande Detector

Super-Kamiokande is a 50 kton water Cherenkov detector in Japan. One of the main physics goals is to test Grand Unified Theory by searching for proton decay. The $p\to e^+\pi^0$ and $p\to \mu^+\pi^0$ decay modes are the most prospective because they are predicted in many theories, and because of their unique event topologies, signal and atmospheric neutrino background events that can be clearly discriminated experimentally. Super-Kamiokande has been operating from April 1996 and accumulated a large amount of data with a great potential for discovery. In order to further improve the search sensitivity, we have enlarged the fiducial mass of the Super-Kamiokande detector by 20% and added 25% more exposure by livetime update since the last published results in 2017, resulting in 1.5 times larger statistics. In this talk, the latest proton decay search results, especially via $p\to e^+\pi^0$ and $p\to \mu^+\pi^0$ modes with the larger fiducial mass will be presented.

Speaker: Akira Takenaka (University of Tokyo)

TAKENAKA.PDK.ICHEP.20200728.pdf

16 Search for heavy neutral leptons decaying into muon-pion pairs in the MicroBooNE detector

We will present upper limits on the production of heavy neutral leptons (HNLs) decaying to muon-pion pairs using data collected with the MicroBooNE liquid-argon time projection chamber (TPC) operating at Fermilab. This search is the first of its kind performed in a liquid-argon TPC and the first beyond the Standard Model result obtained with the MicroBooNE detector. We use data collected in 2017 and 2018 corresponding to an exposure of 2 x 1020 protons on target from the Fermilab Booster Neutrino Beam, which produces mainly muon neutrinos with an average energy of about 800 MeV. HNLs with higher mass are expected to have a longer time-of-flight to the liquid-argon TPC than Standard Model neutrinos. The data are therefore recorded with a dedicated trigger configured to detect HNL decays that occur after the neutrino spill reaches the detector. We set upper limits at the 90\% confidence level on the element U_mu2 of the extended PMNS mixing matrix in the range for Dirac HNLs and Majorana HNLs, assuming HNL masses between 260 and 385 MeV.

Speaker: Owen Robert Young Goodwin (University of Manchester (GB))

ICHEP_talk_HNL_ogoodwin.pdf

17 Explaining the SM flavor structure with grand unified theories

We do not know why there are three fermion families in the Standard Model (SM), nor can we explain the observed pattern of fermion masses and mixing angles. Standard grand unified theories based on the SU(5) and SO(10) groups fail to shed light on this issue, since they also contain three copies of fermion representations of an enlarged gauge group.

However, it does not need to be so. In this talk, I will discuss the possibility that the Standard Model families are distributed over distinct representations of a grand unified model, in which case the gauge symmetry itself might discriminate the various families and explain (at least partially) the flavor puzzle.

Speaker: Renato Fonseca (IPNP, Charles University, Prague)

ICHEP2020-RenatoFonseca.pdf

ICHEP2020-RenatoFonseca.pptx

18 A new program of searches for baryon number violation via neutron conversions at ORNL and the ESS

Searches for free neutrons converting to anti-neutrons (|ΔB|=2) and/or sterile neutrons (|ΔB|=1) play a distinctive and complementary role in the worldwide program of baryon number violation searches. These searches provide an important test of a global symmetry that must be violated to create a baryon asymmetry in the universe, and offer a unique portal to a dark sector through these feeble interactions. An international collaboration has developed a staged program of searches for neutron conversions at Oak Ridge National Laboratory and the European Spallation Source, which will allow both precision searches and research and development for subsequent stages, culminating in an ultimate improvement in sensitivity of around three orders of magnitude compared with earlier work. We will outline this program and present results of the first-stage search for neutron conversions to sterile neutrons in large magnetic fields, suggested to explain the long-standing neutron lifetime anomaly.

Speaker: Leah Broussard (Oak Ridge National Laboratory)

ICHEP 2020 n-nbar LJB.pptx

5:45 PM Coffee Break

19 Searching for new resonances in partially-hadronic states in ATLAS

Many extensions to the Standard Model predicts new particles decaying into two bosons (VV, VH, Vgamma) making these important signatures in the search for new physics. Searches for such diboson resonances have been performed in final states with different numbers of leptons, photons and jets where new jet substructure techniques to disentangle the hadronic decay products in highly boosted configuration are being used. This talk summarizes ATLAS searches for diboson resonances with LHC Run 2 data in semileptonic final states.

Speaker: Stefan Raimund Maschek

ICHEP_SemileptonicResonanceSearch_StefanRaimundMaschek.pdf

20 Search for new phenomena in leptonic final states at CMS

Many new physics models, e.g., compositeness, extra dimensions, extended Higgs sectors, supersymmetric theories, and dark sector extensions, are expected to manifest themselves in the final states with leptons and photons. This talk presents searches in CMS for new phenomena in the final states that include leptons and photons, focusing on the recent results obtained using the full Run-II data-set collected at the LHC.

Speaker: Saranya Samik Ghosh (RWTH, III. Physik. Inst. A)

ICHEP2020_BSM_CMSExoticLeptonic_SGhosh.pdf

ICHEP2020_BSM_CMSExoticLeptonic_SGhosh_withTransitions.pdf

21 Search for new physics with unconventional signatures at CMS

Many extensions to the standard model predict new particles and phenomena that may produce unique and unconventional signatures at the LHC. This talk presents results from searches that look for such unconventional signatures using novel reconstruction techniques in CMS with the full Run-II data-set collected at the LHC

Speaker: Brian Francis (The Ohio State Univ.)

bfrancis_ichep2020.pdf

22 Search for new physics using final states with photons at CMS

Several theories of physics beyond the standard model predict new phenomena and interactions involving photons. This talk covers searches for new physics performed using data collected with the CMS detector at the LHC, which target final states consisting of photons.

Speaker: Justin Andrew Williams (The Univ. of Kansas)

final_states_with_photons.pdf

23 Searches for new heavy resonances in hadronic final states with the ATLAS detector

Many theories beyond the Standard Model predict new phenomena which decay to jets. These are of particular interest at the LHC since new phenomena produced in parton collisions are likely to produce final states with (at least) two partons. This talk presents the latest 13 TeV ATLAS results, covering exclusive searches for dijet resonances along with searches for dijet events produced in association with additional particles such as an additional isolated lepton, which overcomes the trigger limitations to extend to lower dijet masses.

Speaker: Jeremy Robert Love (Argonne National Laboratory (US))

ICHEP2020_HadroRes_v1.pdf

24 Searches for vector-like quarks at CMS

We present results of searches for massive vector-like top and bottom quark partners using proton-proton collision data collected with the CMS detector at the CERN LHC at a center-of-mass energy of 13 TeV. Single and pair production of vector-like quarks are studied, with decays into a variety of final states, containing top and bottom quarks, electroweak gauge and Higgs bosons. We search using several categories of reconstructed objects, from multi-leptonic to fully hadronic final states. We set exclusion limits on both the vector-like quark mass and cross sections, for combinations of the vector-like quark branching ratios.

Speaker: Julie Hogan (Brown Univ.)

CMSVLQ_ICHEP2020.pdf

25 Fully Hadronic Diboson searches in ATLAS

Many extensions to the Standard Model predicts new particles decaying into two bosons (W, Z, photon, or Higgs bosons) making these important signatures in the search for new physics. Searches for such diboson resonances have been performed in different final states and new jet substructure techniques to disentangle the hadronic decay products in highly boosted configuration are being used. Novel analysis techinques, unsupervised learning, are also used to extract new feature from the data. This talk summarizes recent ATLAS diboson searches with LHC Run 2 data in fully hadronic final state.

Speaker: Steven Schramm (Universite de Geneve (CH))

StevenSchramm-FullHadDibosonSearches.pdf

26 Search for new new phenomena using jets at CMS

Many new physics models, e.g., compositeness, extra dimensions, extended Higgs sectors, supersymmetric theories, and dark sector extensions, are expected to manifest themselves in the final states with hadronic jets. This talk presents searches in CMS for new phenomena in the final states that include jets, focusing on the recent results obtained using the full Run-II data-set collected at the LHC.

Speaker: Dimitrios Karasavvas (Univ. of Athens)

ICHEP_jet_presentation.pdf

27 Search for millicharged particles at the LHC with the milliQan prototype

In this talk, I will present the results of a recent search for fractionally charged particles using a data sample of proton-proton collisions provided by the CERN Large Hadron Collider in 2018. This search was carried out with a prototype scintillator-based detector, which allows the first sensitivity to particles with charges ≤0.1e at a hadron collider. The existence of new particles with masses between 20 and 4700 MeV is excluded at 95% confidence level for charges between 0.006e and 0.3e, depending on their mass. New sensitivity is achieved for masses larger than 700 MeV. I will discuss the concept of the experiment, the results of the search, and the plan for the full milliQan detector given the successful operation of the prototype.

Speaker: Matthew Daniel Citron (Univ. of California Santa Barbara (US))

milliQan_ICHEP_MC.pdf

28 Search for non-Newtonian gravity with optically-levitated microspheres

The universal law of gravitation has undergone stringent tests for many decades over a significant range of length scales, from atomic to planetary. Of particular interest is the short distance regime, where modifications to Newtonian gravity may arise from axion-like particles or extra dimensions. We have constructed an ultra-sensitive force sensor based on optically-levitated microspheres with a force sensitivity of $10^{-17}$ N/$\sqrt{\rm Hz}$ for the purpose of investigating non-Newtonian forces in the 1-100 $\mu$m range. Microspheres interact with a variable-density attractor mass made by alternating silicon and gold segments with periodicity of 50 $\mu$m. The attractor can be located as close as 10 $\mu$m from a microsphere. I describe the characterization of this system, its sensitivity, and some preliminary results. Further technological developments to reduce background are expected to provide orders of magnitude improvement in the sensitivity, probing beyond current constraints on non-Newtonian interactions.

Speaker: Dr Nadav Priel (Stanford University)

ICHEP2020_v1.pdf

Computing and Data Handling: Session I - Premiere

Conveners: Elisabetta Maria Pennacchio (Centre National de la Recherche Scientifique (FR)), Dagmar Adamova (Czech Academy of Sciences (CZ))

Replay

29 Application of Quantum Machine Learning to High Energy Physics Analysis at LHC using IBM Quantum Computer Simulators and IBM Quantum Computer Hardware

Using IBM Quantum Computer Simulators and Quantum Computer Hardware, we have successfully employed the Quantum Support Vector Machine Method (QSVM) for a ttH (H to two photons), Higgs production in association with a top quark pair analysis at the LHC.

We will present our experiences and results of a study on LHC high energy physics data analysis with IBM Quantum Computer Simulators and IBM Quantum Computer Hardware using IBM Qiskit. The work is in the context of a Qubit platform. Taking into account the limitation of a low number of qubits, the result using the Quantum Computer Simulators expressed in a ROC curve is comparable with the results using classical machine learning methods (BDT and classical SVM). This study is applied to a ttH physics analysis, one of the flagship physics channels at the LHC, with 5 qubits, 100 training events and 100 test events. Here the ROC curve is defined as the Receiver Operating Characteristics curve in the plane of background rejection versus signal efficiency.

In addition, we have employed the IBM QSVM Variational quantum machine learning algorithm using 5 qubits on the IBM Quantum Computer Hardware of 20 qubits (“IBM Boeblingen”), with 100 training events and 100 test events, again for a ttH (H to two photons) analysis at the LHC. The present result from the IBM Quantum Hardware is about 10% in performance below the Quantum Simulation.

The work is performed by an international and interdisciplinary collaboration with Department of Physics and Department of Computer Sciences of University of Wisconsin, CERN Openlab of IT Division, IBM Research Zurich and Fermilab Quantum Institute.

This work pioneers a close collaboration of academic institutions with industrial corporations in a High Energy Physics analysis effort.

Speaker: Chen Zhou (University of Wisconsin Madison (US))

QMLHEP_ICHEP2020.pdf

30 On the impact of modern deep-learning techniques to the performance and time-requirements of classification models in experimental high-energy physics

Beginning from a basic neural-network architecture, we test the potential benefits offered by a range of advanced techniques for machine learning and deep learning in the context of a typical classification problem encountered in the domain of high-energy physics, using a well-studied dataset: the 2014 Higgs ML Kaggle dataset. The advantages are evaluated in terms of both performance metrics and the time required to train and apply the resulting models. Techniques examined include domain-specific data-augmentation, learning rate and momentum scheduling, (advanced) ensembling in both model-space and weight-space, and alternative architectures and connection methods. Following the investigation, we arrive at a model which achieves equal performance to the winning solution of the original Kaggle challenge, whilst requiring about 2% of the training time and less than 5% of the inference time using much less specialised hardware. Additionally, a new wrapper library for PyTorch called LUMIN is presented, which incorporates all of the techniques studied.

Speaker: Giles Chatham Strong (Universita e INFN, Padova (IT))

GS_ICHEP_28-07-20.pdf

Paper

Study code

31 Hello RNTuple and friends: what the new ROOT means for your analysis

ROOT is one of HEP's most senior active software projects; virtually every physicist uses it, and its TTree is the backbone of HEP data. But ROOT can do even better - and it's getting there, step by step. It now features RDataFrame, a new, simple and super-fast way to write a data analysis. Soon TTree will have a successor, RNTuple, allowing for even faster data processing. Graphics will become web-based, sleek, and right-by-default. Python interfaces are promoted to become a first class citizen, and even histograms will see a new generation with more obvious, simpler interfaces and higher speed. This presentation will feature a sneak preview for all of this - because we do this for you, and we want your comments to get it right, for the next 30 years.

Speaker: Axel Naumann (CERN)

Naumann-ROOT-ICHEP-2020.pdf

4:30 PM Coffee break

virtual conference

32 What the new RooFit can do for your analysis

RooFit is a toolkit for statistical modelling and fitting, and together with RooStats it is used for measurements and statistical tests by most experiments in particle physics.
Since one year, RooFit is being modernised. In this talk, improvements already released with ROOT will be discussed, such as faster data loading, vectorised computations and more standard-like interfaces. These allow for speeding up unbinned fits by several factors, and make RooFit easier to use from both C++ and python.
Furthermore, an overview of features in development is given, such as a fast implementation of "HistFactory" computations, easier data loading, and the prospects for RooFit computations on GPUs.

Speaker: Stephan Hageboeck (CERN)

20.07_RooFit_ICHEP.pdf

33 Automated selection of particle-jet features for data analysis inHigh Energy Physics experiments

In high-energy physics experiments, the sensitivity of selection-based analyses critically depends on which observable quantities are taken into consideration and which ones are discarded as considered least important. In this process, scientists are usually guided by their cultural background and by literature.
Yet simple and powerful, this approach may be sub-optimal when machine learning strategies are envisaged and potentially all features are usable. On the other hand, training multivariate algorithms with all available features is often impossible, due to lack of calibration or computing power limitations. How to robustly choose the set of observables to use in a modern high-energy physics analysis?
We show here that it is possible to rank the relative importance of all available features in an automated fashion by engineering a fast and powerful classification model.
Features are sorted with the Random Forest algorithm, then selected as input quantities for a Deep Learning Neural Network. We make it explicit the relation between Random Forest importance ranking and signal-to-background ratio increase, varying the number of features to feed the Neural Network with. We benchmark our procedure with the case of highly boosted di-jet resonances decaying to two b~quarks, to be selected against an overwhelming QCD background. Promising results from Monte Carlo simulation with HEP pseudo-detectors are shown.

Speaker: Mr Andrea Di Luca (Universita degli Studi di Trento and INFN (IT))

ichep2020_diluca.pdf

34 Data Analysis with GPU-Accelerated Kernels

At HEP experiments, processing billions of records of structured numerical data can be a bottleneck in the analysis pipeline. This step is typically more complex than current query languages allow, such that numerical codes are used. As highly parallel computing architectures are increasingly important in the computing ecosystem, it may be useful to consider how accelerators such as GPUs can be used for data analysis. Using CMS and ATLAS Open Data, we implement a benchmark physics analysis with GPU acceleration directly in Python based on efficient computational kernels using Numba/LLVM, resulting in an order of magnitude throughput increase over a pure CPU-based approach. We discuss the implementation and performance benchmarks of the physics kernels on CPU and GPU targets. We demonstrate how these kernels are combined to a modern ML-intensive workflow to enable efficient data analysis on high-performance servers and remark on possible operational considerations.

Speaker: Irene Dutta (California Institute of Technology (US))

Data_Analysis_with_GPU-Accelerated_Kernels_IreneDutta.pdf

5:50 PM Coffee break

35 Parallelization for HEP Event Reconstruction

We report on developments targeting a boost in the utilization of parallel computing architectures in HEP reconstruction, particularly for LHC experiments and for neutrino experiments using Liquid Argon Time-Projection Chamber (LArTPC) detectors. Key algorithms in the reconstruction workflows of HEP experiments were identified and redesigned: charged particle track reconstruction for CMS, and hit finding for LArTPC detectors such as ICARUS and MicroBooNE. These algorithms are some of the most time-consuming steps of the event reconstruction, and optimizing their computational performance is key to defining the computing needs for the reconstruction software of the next-generation HEP experiments. With the use of advanced profiling tools and development techniques, the algorithms have been rewritten so that they can take full advantage of multi-threading and vectorization on modern multicore CPUs, while at the same time satisfying physics performance goals. On a single thread, the modified versions are faster than the original algorithms by a factor ranging from 6 to 12x, depending on the application, and both the track reconstruction and hit finder algorithms have been integrated into the experiments’ reconstruction software. Portable implementations of the algorithms for usage at supercomputers and with heterogenous platforms have been explored.

Speakers: Giuseppe Cerati (Fermi National Accelerator Lab. (US)), Allison Reinsvold Hall (Fermilab), Giuseppe Cerati (Fermi National Accelerator Lab. (US))

hepreco-ichep2020.pdf

36 Using an Optical Processing Unit for tracking and calorimetry at the LHC

The High Luminosity Large Hadron Collider is expected to have a 10 times higher readout rate than the current state, significantly increasing the computational load required. It is then essential to explore new hardware paradigms. In this work we consider the Optical Processing Units (OPU) from LightOn, which compute random matrix multiplications on large datasets in an analog, fast and economic way, fostering faster machine learning results on a dataset of reduced dimension. We consider two case studies.

1) “Event classification”: high energy proton collision at the Large Hadron Collider have been simulated, each collision being recorded as an image representing the energy flux in the detector. The task is to train a classifier to separate a Susy signal from the background. The OPU allows fast end-to-end classification without building intermediate objects (like jets). This technique is presented, compared with more classical particle physics approaches.

2) “Tracking”: high energy proton collisions at the LHC yield billions of records with typically 100,000 3D points corresponding to the trajectory of 10.000 particles. Using two datasets from previous tracking challenges, we investigate the OPU potential to solve similar or related problems in high-energy physics, in terms of dimensionality reduction, data representation, and preliminary results.

Speaker: Laurent Basara (LAL/LRI, Université Paris Saclay)

200728_ICHEP_Basara_OPU.pdf

Dark Matter Detection: Session I - Premiere

Conveners: Dr Silvia Scorza (SNOLAB), Torben Ferber (DESY)

Replay

37 New Inelastic Channels for Sub-GeV Dark Matter Scattering

As the search for dark matter continues down to lower and lower masses, the kinematics of sub-GeV dark
matter scattering require moving beyond the approximation of free-particle scattering. I will describe two inelastic
channels relevant for sub-GeV dark matter detection which necessarily involve the condensed matter properties of
common detector materials: the Migdal effect in liquid nobles, and plasmon excitation in semiconductors. I will
outline the theoretical basis for these processes, discuss the importance of many-body effects in accurately
predicting the scattering rates, and speculate on whether these processes have already been observed at numerous
experiments.

Speaker: Yonatan Kahn (University of Illinois)

Mail to yfkahn@illinois.edu if you have any further questions!

New_Inelastic_Channels_subGeV.pdf

38 Dark Matter - phonon scattering

Light dark matter interacting in a crystal or fluid must scatter off a
collective excitation (phonon) rather than off individual nuclei. I will
set up the appropriate low energy effective theory and show how to
calculate the dark matter scattering rate for various dark matter models
and target materials.

Speaker: Simon Knapen (CERN)

ICHEP_phonons.pdf

Zoom discussion

39 String fragmentation in supercool confinement as a new dark matter production mechanism

A new strongly-coupled sector can feature a supercooled confinement transition in the early universe. When fundamental quanta of the strong sector are swept into expanding bubbles of the confined phase, the distance between them is large compared to the confinement scale. The string of flux linking the fundamental quanta fragments and in the process produces an enhanced number of composite states. Furthermore, the resulting composite states are highly boosted in the CMB frame, which leads to additional particle production through the subsequent deep inelastic scattering. This opens several new avenues of investigation, in this talk I will focus on the one related to the composite dark matter relic density.

Speaker: Filippo Sala (LPTHE)

FSala_ICHEP_Jul20.pdf

4:45 PM Coffee break

40 Recent Searches for Hidden-Sector Particles with BABAR

Many models of dark matter and hidden sectors predict new particles with masses below the electroweak scale. Low-energy electron-positron colliders such as BABAR are ideally suited to discover these hidden-sector particles. We present several recent BABAR searches for low-mass hidden- sector particles, including new searches for prompt and long-lived leptonically decaying hidden scalars produced in association with tau leptons. This search is sensitive to viable models that could account for the muon $g-2$ excess. We also present results a search for dark muonic forces, and for invisible particles produced in six-quark final states. These examples show the importance of $B$-factories in constraining and discovering new hidden-sector physics beyond the Standard Model.

Speaker: Yunxuan Li (California Institute of Technology)

ICHEP_Hidden_Sector_BaBar.pdf

41 Search for an Axion-Like Particle in B -> K a, with a -> gamma gamma at BABAR

Many extensions of the Standard Model include the possibility of light new particles, such as axions or dark matter candidates. These scenarios can be probed using the large data sets collected by $B$-factories, complementing measurements performed at the LHC.
We report on a search for an Axion-like particle (ALP), $a$, produced in the Flavor-Changing Neutral-Current decay $B\to K a$, with $a\to \gamma\gamma$, which is expected to be competitive with the corresponding Standard-Model electroweak processes. This search, performed by using a dataset of about 470 million $B\bar{B}$ pairs collected by the $BABAR$ experiment at the PEP-II $e^+e^-$ collider, is sensitive to ALP masses in the range 0 - 4.78 GeV.

Speaker: Brian Shuve (Harvey Mudd College)

Shuve_ICHEP_BABAR_ALP.pdf

Zoom discussion

42 Dark Sector first results at Belle II

The Belle II experiment at the SuperKEKB energy-asymmetric $e^+ e^-$ collider
is a substantial upgrade of the B factory facility at the Japanese KEK laboratory.
The design luminosity of the machine is $8\times 10^{35}$ cm$^{-2}$s$^{-1}$ and
the Belle II experiment aims to record 50 ab$^{-1}$ of data, a factor of 50 more
than its predecessor. During 2018, the machine has completed a commissioning run,
recording a data sample of about 0.5 fb$^{-1}$. Main operations started in
March 2019 with the complete Belle II detector: an integrated luminosity
of 10 fb$^{-1}$ has been collected so far. These early data sets,
with specifically designed low multiplicity triggers, offer already the
possibility to search for a large variety of dark sector particles in
the GeV mass range, complementary to LHC and to dedicated low energy experiments.
The talk will review the status of the dark sector searches at Belle II, with a focus
on the discovery potential of the early data, and show the first results.

Speaker: Enrico Graziani (Universita' di Roma III)

graziani-ichep2020.pdf

6:15 PM Coffee break

43 DarkSide-20k and the Direct Dark Matter Search with Liquid Argon

Dual phase noble liquid Time Projection Chambers (TPCs) offer a
competitive and scalable way to search for dark matter directly via
elastically scattering off of detector target nuclei and electrons.
The Global Argon Dark Matter Collaboration (GADMC) is undertaking an
ambitious global program from the extraction and purification of
Underground Argon (UAr), depleted in 39Ar which reduces the internal
background, to the development of $25 cm^2$ Silicon Photo Multiplier
(SiPM) modules capable of resolving single photoelectrons.
DarkSide-20k is the next stage of this program and will be the next
generation dual phase Argon TPC. DarkSide-20k will be housed in the
Gran Sasso underground laboratory (LNGS) and has an exposure goal of
~100 tonne-years with zero instrumental background in expectation of a
WIMP-nucleon cross section of $10^{-47} cm^2$ for a WIMP mass of 1TeV/$c^2$
during a 5-year run. An overview of the DarkSide experimental program
will be presented with a focus on the upcoming DarkSide-20k detector
and the new technologies involved.

Speaker: Dr Luigi Pio Rignanese (Universita e INFN, Bologna (IT))

DS_ICHEP2020.pdf

Zoom discussion

44 The Light Dark Matter eXperiment, LDMX

The constituents of dark matter are still unknown, and the viable possibilities span a very large mass range. Specific scenarios for the origin of dark matter sharpen the focus on a narrower range of masses: the natural scenario where dark matter originates from thermal contact with familiar matter in the early Universe requires the DM mass to lie within about an MeV to 100 TeV. Considerable experimental attention has been given to exploring Weakly Interacting Massive Particles in the upper end of this range (few GeV – ~TeV), while the region ~MeV to ~GeV is largely unexplored. Most of the stable constituents of known matter have masses in this lower range, tantalizing hints for physics beyond the Standard Model have been found here, and a thermal origin for dark matter works in a simple and predictive manner in this mass range as well. It is therefore a priority to explore. If there is an interaction between light DM and ordinary matter, as there must be in the case of a thermal origin, then there necessarily is a production mechanism in accelerator-based experiments. The most sensitive way, (if the interaction is not electron-phobic) to search for this production is to use a primary electron beam to produce DM in fixed-target collisions. The Light Dark Matter eXperiment (LDMX) is a planned electron-beam fixed-target missing-momentum experiment that has unique sensitivity to light DM in the sub-GeV range. This contribution will give an overview of the theoretical motivation, the main experimental challenges and how they are addressed, as well as projected sensitivities in comparison to other experiments.

Speaker: Andrew James Whitbeck (Texas Tech University (US))

LDMX_ICHEP_2020_final.pdf

Zoom discussion

45 Dark Matter searches with the ATLAS detector

The presence of a non-baryonic dark matter (DM) component in the Universe is inferred from the observation of its gravitational interaction. If dark matter interacts weakly with the Standard Model it would be produced at the LHC, escaping the detector and leaving a large missing transverse momentum as their signature. The ATLAS detector has developed a broad programme to directly search for DM. The results of  recent searches on 13 TeV pp data, their interplay and interpretation will be presented.

Speaker: Ben Carlson (University of Pittsburgh)

Carlson_DarkMatterATLAS_ICHEP_July28_2020.pdf

Detectors for Future Facilities (incl. HL-LHC), R&D, Novel Techniques: Session I - Premiere

Convener: Petra Merkel (Fermi National Accelerator Lab. (US))

Replay

46 The CMS Tracker Upgrade for the High Luminosity LHC

The LHC machine is planning an upgrade program which will smoothly bring the luminosity to about $5-7.5\times10^{34}$cm$^{-2}$s$^{-1}$, to possibly reach an integrated luminosity of $3000-4000\;$fb$^{-1}$ over about a decade. This High Luminosity LHC scenario, HL-LHC, starting in 2027, will require an upgrade program of the LHC detectors known as Phase-2 upgrade. The current CMS Outer Tracker, already running beyond design specifications, and CMS Phase-1 Pixel Detector will not be able to survive HL-LHC radiation conditions and CMS will need completely new devices, in order to fully exploit the highly demanding conditions and the delivered luminosity. The new Outer Tracker should have also trigger capabilities. To achieve such goals, R\&D activities have explored options for both the Outer Tracker and for the Inner Tracker. The solutions developed will allow to include tracking information in the first level trigger stage. The design choices for the Tracker upgrades are discussed along with some highlights on technological approaches and R\&D activities.

Speaker: Katja Klein (RWTH, I. Physik. Inst.)

ICHEP2020_KatjaKlein.pdf

47 ATLAS ITk Pixel Detector Overview

For the HL-LHC upgrade the current ATLAS Inner Detector is replaced by an all-silicon system. The Pixel Detector will consist of 5 barrel layers and a number of rings, resulting in about 14 m2 of instrumented area. Due to the huge non-ionizing fluence (1e16 neq/cm2) and ionizing dose (5 MGy), the two innermost layers, instrumented with 3D pixel sensors (L0) and 100μm thin planar sensors (L1) will be replaced after about 5 years of operation. All hybrid detector modules will be read out by novel ASICs, implemented in 65nm CMOS technology, with a bandwidth of up to 5 Gb/s. Data will be transmitted optically to the off-detector readout system. To save material in the servicing cables, serial powering is employed for low voltage. Large scale prototyping programs are being carried out by all sub-systems. The talk will give an overview of the layout and current status of the development of the ITk Pixel Detector.

Speaker: Stefano Terzo (IFAE Barcelona (ES))

terzo_ITk.pdf

48 The ATLAS ITk Strip Detector System for the Phase-II LHC Upgrade

The ATLAS experiment at the Large Hadron Collider is currently preparing for a major upgrade of the Inner Tracking for the Phase-II LHC operation (known as HL-LHC), scheduled to start in 2026. In order to achieve the integrated luminosity of 4000 fb-1, the instantaneous luminosity is expected to reach unprecedented values, resulting in about 200 proton-proton interactions in a typical bunch crossing. The radiation damage at the full integrated luminosity implies integrated hadron fluencies over 2x10^16 neq/cm2 requiring a complete replacement of the existing Inner Detector. An all-silicon Inner Tracker (ITk) is under development with a pixel detector surrounded by a strip detector, aiming to provide increased tracking coverage up to |η|=4.
The ITk Strip Detector system consisting of four barrel layers in the centre and forward regions composed of six disks at each end, is described in the ATLAS Inner Tracker Strip Detector Technical Design Report (TDR). With the recent completion of Final Design Reviews (FDRs) in a number of key areas, such as Sensors, Modules, ASICs and Front-end electronics, the prototyping phase has been completed successfully. The pre-production phase is about to start at the institutes involved.
In this contribution we present an overview of the ITk Strip Detector System, including the final layout of the ITk Strip Detector System, and highlight the final design choices of sensors, module designs and ASICs. We will give an extended summary of the R&D results achieved in the prototyping phase. Some of the modules were irradiated with a range of fluencies and reaching up to and in some cases exceeding HL-LHC doses, demonstrating the excellent radiation hardness achieved. In addition, we will outline the current status of pre-production on various detector components, with an emphasis on QA and QC procedures. We will also discuss the status of preparations and the plans for the forth- coming pre-production and production phase.

Speaker: Dennis Sperlich (Albert Ludwigs Universitaet Freiburg (DE))

ITk_Sperlich.pdf

49 The LHCb VELO Upgrade Programme for High Luminosity running at the LHC and HL-LHC

The detector currently under construction is designed to run throughout Run 3 and 4, after which a further major Upgrade will be implemented to enable the LHCb Upgrade II physics goals. The Upgrade II detector is designed to run at instantaneous luminosities of 2 × $10^{34}cm^{-2}s^{-1}$, an order of magnitude above Upgrade I, and accumulate a sample of more than 300 fb-1. At this intensity, the mean number of visible proton- proton interactions per crossing would be 56, producing around 2500 charged particles within the LHCb acceptance. The Upgrade II programme is reliant on an efficient and precise vertex detector (VELO). This subdetector enables real time reconstruction of tracks from all LHC bunch crossings in the software trigger system. The Upgrade II luminosity poses significant challenges which necessitate the construction of a new VELO with enhanced capabilities. Compared to Upgrade I there will be a further order of magnitude increase in data output rates accompanied by corresponding increases in radiation levels and occupancies. To cope with the large increase in pile-up, new techniques to assign correctly each b hadron to the primary vertex from which it originates, and to address the challenge of real time pattern recognition, are needed. These challenges will be met by the development of a new 4D hybrid pixel detector with enhanced rate and timing capabilities in the ASIC and sensor. Improvements in the mechanical design of the Ugrade II VELO will also be needed to allow for periodic module replacement. The design will be further optimised to minimise the material before the first measured point on a track (which is dominated by the secondary vacuum enclosure) and to achieve a more fully integrated module design with thinned sensors and ASICs combined with a lightweight cooling solution. It is envisaged that the readout ASIC will follow the VeloPix /Timepix4 development path with a novel design will including in-pixel timing and calibration, allowing the pixel time stamps to reach a precision of 10s of picoseconds, and a new custom output serialiser will be included. The R&D programme will explore the capabilities of combining fast timing information with small pixel size, and examine clock distribution issues for fine timing over a full system. The capabilities of the sensor to deliver fast timing will be explored for different sensor designs. The needs of the Upgrade II VELO will be outlined, along with the R&D steps envisaged to achieve the goal of a 4D pixel tracker.

Speaker: Timothy David Evans (CERN)

slides_ichep2020.pdf

50 ALICE upgrades for LHC Run 4 and beyond

While ALICE is currently undergoing major upgrades which will come online for LHC Run 3 (starting in 2021), further projects are already on their way. ALICE is developing thinned wafer-sized monolithic active pixel sensors to replace the inner tracking layers in the Long Shutdown 3 (starting in 2025). This resulting detector will have an unprecedentedly low material budget, and consequently drastically reduced interaction probabilities and unparalleled vertexing performance. Furthermore, we will present the plans for the installation of a Forward Calorimeter (FoCal) comprising a Si-W electromagnetic calorimeter with pad and pixel readout and a hadronic calorimeter with conventional metal-scintillator technology with optical readout, covering 3.4 < eta < 5.8. Finally, we will present ideas for a thin, light, fast detector fully based on silicon sensors for tracking, time-of-flight and shower measurements. This combines the advantages of extremely low material budget, fast read-out and high resolution which will enable novel measurements of electromagnetic and hadronic probes of the QGP at very low momentum.

Speaker: Andrea Rossi (Universita e INFN, Padova (IT))

Rossi_ICHEP2020_UpgradeALICE_v5.pdf

51 Level-1 Track Finding at CMS for the HL-LHC

The success of the CMS physics program at the HL-LHC requires maintaining sufficiently low trigger thresholds to select processes at the electroweak scale. With an average expected 200 pileup interactions, critical to achieve this goal while maintaining manageable trigger rates is in the inclusion of tracking information in the Level-1 (L1) trigger. A 40 MHz silicon-based track trigger on the scale of the CMS detector has never before been built; it is a novel handle, which in addition to maintaining trigger rates can enable entirely new physics studies.

The main challenges of reconstructing tracks in the L1 trigger are the large data throughput at 40 MHz and the need for a trigger decision within 12.5 µs. To address these challenges, the CMS outer tracker for HL-LHC uses modules with closely-spaced silicon sensors to read out only the hits compatible with charged particles above 2-3 GeV ("stubs"). These are used in the back-end L1 track finding system, implemented using commercially available FPGA technology. The ever-increasing capability of modern FPGAs combined with their programming flexibility are ideal for implementing fast track finding algorithms. The proposed reconstruction algorithm forms track seeds ("tracklets") from pairs of stubs in adjacent layers of the outer tracker. These seeds provide roads where consistent stubs are included to form track candidates. Track candidates sharing multiple stubs are combined prior to being fitted. A Kalman Filter track fitting algorithm is employed to identify the final track candidates and determine the track parameters. The system is divided into nine sectors in the r-phi plane, and time-multiplexed by a factor of 18, so that each event in one sector is processed by a dedicated track finding board.

This presentation will discuss the CMS L1 track finding algorithm and its implementation, present simulation studies of estimated performance, and show recent results from a scalable system demonstrator based on prototype hardware.

Speaker: Andrew Evan Hart (Rutgers University)

ichep_20200728.pdf

52 The CMS Trigger system for the HL-LHC

The CMS experiment has been designed with a two-level trigger system: the Level 1 Trigger, implemented on custom-designed electronics, and the High Level Trigger, a streamlined version of the CMS oeconstruction software running on a computer farm. During its “Phase 2” the LHC will reach a luminosity of 7X10^34 cm-2 sec-1 with a pileup of 200 collisions, integrating more than 3000 fb-1 over the full experimental run. To fully exploit the higher luminosity, the CMS experiment will introduce a more advanced Level 1 Trigger and increase the full readout rate from 100 kHz to 750 kHz. The higher luminosity, event complexity and input rate present an unprecedented challenge to the High Level Trigger, that aims to achieve a similar efficiency and rejection factor as today despite the higher pileup and more pure preselection. The ongoing studies and prospects for the online reconstruction and selection algorithms will be discussed.

Speaker: Alexandre Zabi (LLR, Ecole Polytech., IN2P3-CNRS)

CMSPhaseIITrigger_AZABI_ICHEP2020.pdf

53 Precision Luminosity Measurement with the CMS detector for HL-LHC

The High Luminosity upgrade of the LHC (HL-LHC) is foreseen to increase the instantaneous luminosity by a factor of five to seven times the LHC nominal design value. The resulting, unprecedented requirements for background monitoring and luminosity measurement create the need for new high-precision instrumentation at CMS, using radiation hard detector technologies. This contribution presents the strategy for bunch-by-bunch online luminosity measurement based on various detector technologies. A main component of the system is the Tracker Endcap Pixel Detector (TEPX) with an additional 75 kHz of dedicated triggers for online measurement of luminosity and beam-induced background. Real-time implementations of algorithms such as pixel cluster counting on an FPGA are explored for online processing of the resulting data. The potential of the exploitation of the Outer Tracker, the Hadron Forward calorimeter and muon trigger objects will also be discussed.

Speaker: Gabriella Pasztor (Eotvos Lorand University)

ICHEP_HLLHCLumi_v3d.pdf

54 Development of a System for Abort and Luminosity of the ATLAS Experiment at the HL-LHC based on polycrystalline CVD diamond

The High Luminosity upgrade of Large Hadron Collider (HL-LHC) will increase LHC Luminosity by an order of magnitude increasing the density of particles on the detector by an order of magnitude. For protecting the inner detectors of experiments and for monitoring the delivered luminosity, a radiation hard beam monitor is being developed. We are developing a set of detectors based on poly-crystalline Chemical Vapor Deposition (pCVD) diamonds and a dedicated ASIC. Due to the large range of particle flux through the detector, flexibility is very important. To satisfy the constraints imposed by the HL-LHC, our solution is based on segmenting each single diamond sensor into multiple devices of varying size and reading them out with a new multichannel readout chip. In this talk we describe the proposed system, present preliminary results from the first detectors fabricated using our prototype ASIC and present the noise distribution and efficiency for single MIPs.

Speaker: Prof. Marko Mikuz (Jozef Stefan Institute (SI))

BCM'-ICHEP-Jul20.pdf

BCM'-ICHEP-Jul20.pptx

55 Upgrade of the ATLAS Muon Trigger for the HL-LHC

The present Level-1 Muon Trigger System of the ATLAS experiment will be upgraded for the HL-LHC to the Level-0 (L0) Muon Trigger with increased trigger latency of 10 ms and output rate of 1 MHz. The longer buffers in the front-end allow for more complex processing of the data, maintaining a high trigger efficiency even at highest event rates. For this purpose, the Sector Logic (SL) boards processing data from the RPC and TGC trigger chambers, is complemented by the NSW and MDT Trigger Processors processing respectively the information from the NSW trigger chambers and the MDT precision tracking chambers. To operate the future L0 Muon Trigger, the entire front-end electronics for the RPC, TGC and MDT chambers will be upgraded to cope with required rates and latencies. All RPC and TGC hit data will be transmitted from the front-end boards to the SL and the MDT hits to the MDT Trigger processors in a trigger-less mode over high-speed optical links. The low-resolution coordinates of the muon track hits supplied by the RPC, TGC and NSW trigger chambers will be used as a seed for the MDT Trigger Processors. These seeds provide Regions of Interest (RoIs) and bunch crossing identification. The MDT Trigger Processor assigned to a given sector of MDT chambers then only considers the MDT hits in a RoI, allowing for a large reduction of the relevant data volume. Hits in a RoI, together with the coarse track direction supplied by the trigger chambers, are fed to the MDT Trigger Processor to reconstruct a muon track segment in each MDT chamber and combine the segments into a muon track with significantly improved transverse momentum resolution. The much higher accuracy of the MDT hit coordinates (~0.1 mm) compared to the ones supplied by the primary trigger chambers (20-30 mm), leads to a reduction of the single muon trigger rate by about a factor 3. The MDT Trigger Processor returns the measured pT to the SL for the final muon trigger decision. Upon a L0 trigger accept, it also transmits the MDT hits to the read out system (FELIX) for the final storage. The realisation of the MDT Trigger Processor imposes several technical challenges. To maintain the latency budget, the communication with MDT front-end electronics, the SL and the read out system must be performed via a large number high-speed optical links. The identification of track segments in the RoI also needs fast processors and firmware, which is robust against all possible hit patterns. A hardware demonstrator of the MDT Trigger Processor, based on state-of-the-art FPGA and SoC technology, is currently under production. It is implemented as an ATCA board consisting of two separate modules, the Service Module responsible for the board infrastructure and the Command Module for the data processing. The presentation will cover the description of the new L0 Muon Trigger System and the status of the firmware and hardware development for MDT Trigger Processors.

Speaker: Dr Davide Cieri (Max-Planck-Institut fur Physik (DE))

200728_ICHEP_atlas_muon_dcieri.pdf

6:00 PM Coffee break

56 Test-beam performance of a TORCH prototype module

The TORCH time-of-flight detector is designed to provide a 15 ps timing resolution for charged particles, resulting in K/pi (p/K) particle identification up to 10 (15) GeV/c momentum over a 10 m flight path. Cherenkov photons, produced in a quartz plate of 10 mm thickness, are focused onto an array of micro-channel plate photomultipliers (MCP-PMTs) which measure the photon arrival times and spatial positions. A half-scale (660 x 1250 x 10 mm^3) TORCH demonstrator module instrumented with customised MCP_PMTs has been tested in a 5 GeV/c mixed proton-pion beam at the CERN PS. The MCP-PMTs with the active area 53 x 53 mm^2 and granularity 64 x 8 pixels have been developed in collaboration with an industrial partner (Photek). With 30 photons per particle detected, the 15 ps per particle time resolution requires single-photon resolution of 70 ps. The timing performance and photon yields have been measured as a function of beam position in the radiator, giving measurements which are consistent with expectations. A possible TORCH design of the particle identification system in the LHCb experiment has been simulated and the potential for particle identification performance for high luminosity running has been evaluated.

Speaker: Michal Kreps (University of Warwick (GB))

torchICHEP2020.pdf

57 A High-Granularity Timing Detector for the Phase-II upgrade of the ATLAS Calorimeter system: detector concept, description and R&D and beam test results

The increase of the particle flux (pile-up) at the HL-LHC with luminosities of L ≃ 7.5 × 10^34 cm−2s−1 will have a severe impact on the ATLAS detector reconstruction and trigger performance. The end-cap and forward region where the liquid Argon calorimeter has coarser granularity and the inner tracker has poorer longitudinal vertex position resolution will be particularly affected. A High Granularity Timing Detector (HGTD) is proposed in front of the LAr end-cap calorimeters for pile-up mitigation and for luminosity measurement.

It will cover the pseudo-rapidity range from 2.4 to 4.0. Two Silicon sensors double sided layers will provide precision timing information for MIPs with a resolution better than 30 ps per track in order to assign each particle to the correct vertex. Readout cells have a size of 1.3 mm × 1.3 mm, leading to a highly granular detector with 3 millions of channels. Low Gain Avalanche Detectors (LGAD) technology has been chosen as it provides enough gain to reach the large signal over noise ratio needed. A dedicated ASIC is being developed and some prototypes have been already submitted and measured.

The requirements and overall specifications of the HGTD will be discussed. LGAD R&D campaigns are carried out to study the sensors, the related ASICs, and the radiation hardness. Laboratory and test beam results will be presented.

Speaker: Chiara Rizzi (CERN)

HGTD_ICHEP_2020_chiara_rizzi.pdf

58 Development of the CMS MTD Endcap Timing Layer for HL-LHC

The MIP Timing Detector (MTD) of the Compact Muon Solenoid (CMS) is designed to provide precision timing information (with resolution of ~40 ps per layer) for charged particles, with hermetic coverage up to a pseudo-rapidity of |η|=3. This upgrade will reduce the effects of pileup expected under the High-Luminosity LHC (HL-LHC) running conditions and brings new and unique capabilities to the CMS detector. The time information assigned to each track will enable the use of 4D reconstruction algorithms and will further discriminate in the time domain interaction vertices within the same bunch crossing to recover the track purity of vertices in current LHC conditions. The endcap region of the MTD, called the Endcap Timing Layer (ETL), will be instrumented with silicon-based low gain avalanche detectors (LGADs), covering the high radiation pseudo-rapidity region between |η|=1.6 and 3.0. Each endcap will be instrumented with a two-disk system of LGADs, read out by Endcap Timing Readout Chips (ETROCs), being designed for precision timing measurements. We will go over the motivations for the MTD and will present an overview of the MTD ETL design. We will also present the R&D and test beam studies that were integral for achieving the ETL design, as well as recent progress on the development of the ETROC readout electronics.

Speaker: Karri Folan Di Petrillo (Fermi National Accelerator Lab.)

2020.07.28.kdp.timingICHEP.pdf

59 Precision Timing with the CMS MTD Barrel Timing Layer for HL-LHC

The Compact Muon Solenoid (CMS) detector at the CERN Large Hadron Collider (LHC) is undergoing an extensive Phase II upgrade program to prepare for the challenging conditions of the High-Luminosity LHC (HL-LHC). A new timing detector in CMS will measure minimum ionizing particles (MIPs) with a time resolution of ~30-40 ps and hermetic coverage up to a pseudo-rapidity of |η|=3. The precision time information from this MIP Timing Detector (MTD) will reduce the effects of the high levels of pileup expected at the HL-LHC, enhancing and expanding the physics reach of the CMS detector. For instance, in the analysis of di-Higgs boson production, a timing resolution of 30-40 ps is expected to improve the effective luminosity by about 25% through gains in b-tagging and isolation efficiency. The central Barrel Timing Layer (BTL) will be based on LYSO:Ce crystals read out with silicon photomultipliers (SiPMs). The BTL will use elongated crystal bars, with double-sided read out (a SiPM on each end of the crystal), in order to maximize detector performance within the constraints of space, cost, and channel count. We will present an overview of the MTD BTL design, highlighting some of physics analyses impacted by the MTD. We will review the extensive R&D studies carried out to optimize the BTL design and the test beam results in which the goal of 30 ps timing resolution has been achieved.

Speaker: Nan Lu (California Inst. of Tech.)

ICHEP2020_CMS_BTL_NanLu.pdf

60 The CMS Phase-2 high-granularity 5D calorimeter

The CMS high-granularity endcap calorimeter (HGCAL) is a challenging detector that brings together tracking and calorimetry, silicon and scintillators, as well as linear collider detector concepts, to meet the harsh radiation and pileup environment of the High Luminosity LHC Phase (Phase 2) in the forward region and exploit challenging signatures such as VBF/VBS production. The HGCAL features unprecedented transverse and longitudinal segmentation in both its electromagnetic (ECAL) and hadronic (HCAL) compartments. This information allows to resolve the fine structure of showers, playing to the strengths of particle-flow reconstruction, and allowing to enhance pileup rejection and particle identification, while still achieving good energy resolution. The ECAL and a large fraction of HCAL will be based on hexagonal silicon sensors of 0.5 - 1 cm^{2} cell size. The remainder of the HCAL will be based on highly-segmented scintillators read out by silicon photo-multipliers (SiPM). The intrinsic high-precision timing capabilities of the silicon sensors add a further measurement dimension, critical in event reconstruction, especially for pileup rejection. This presentation will overview the HGCAL project, covering the physics motivation, engineering design, readout and trigger concepts, performance (simulated and from beam tests), as well as ways in which the 5D information content may be exploited by cutting-edge machine learning techniques to enhance the overall physics performance of the forward region.

Speaker: Jeremy Mans (University of Minnesota (US))

HGCAL_ICHEP2020_Mans.pdf

61 Paving the way to reconstruct the 5D information of the CMS HGCAL detector at the HL-LHC

To maintain and improve physics performance under the harsher conditions of the high luminosity LHC phase from 2026, the CMS collaboration has designed a novel endcap calorimeter that uses silicon sensors to achieve radiation tolerance, with the additional benefit of a very high readout granularity. In regions characterised by lower radiation levels, small scintillator tiles with individual SiPM readout are employed. A novel reconstruction approach is being developed to fully exploit the granularity and other significant features of the detector like precision timing, with a view to deployment in the high pileup environment of HL-LHC. An iterative reconstruction framework (TICL) has been put in place, and is being actively developed. The inputs to the framework are clusters of energy deposited in individual calorimeter layers delivered by a density-based algorithm which has recently been developed and tuned. In view of the expected pressure on the computing capacity in the HL-LHC era, the algorithms and their data structured are being designed with GPUs in mind. Preliminary results show that significant speed-up can be obtained running the clustering algorithm on GPUs. In addition, machine learning techniques based on cutting-edge techniques are being investigated and integrated into the reconstruction framework. This talk will describe the approaches being considered and show first results.

Speaker: Jingyu Zhang (Florida State University (US))

jingyu-hgc-ichep-2020.pdf

62 The CMS Muon Spectrometer Upgrade

The luminosity delivered to the experiments by the High Luminosity Large Hadron Collider (HL-LHC) is expected to be at least five times the original design, exceeding the value of 5 × 10^34 cm^−2 s^−1. The detectors will therefore undergo critical upgrades to sustain the higher particle fluxes and improve the tracking and triggering performance. In the current CMS muon system, different detector technologies have been chosen to optimize the CMS detector with respect to performance. Drift Tubes (DT) and Resistive Plate Chambers (RPC) are installed in the barrel, complemented by the two endcaps hosting cathode strip chambers (CSC) and RPC. The upgrade of the Muon Spectrometer will act on the improvement of the electronics installed on DT and CSC and on the extension of the coverage with the installation of additional muon stations in the endcaps - ME0, GE1/1, GE2/1, RE3/1 and RE4/1. Due to the extended lifetime now expected of the LHC experiments (2008-2040) and the significantly larger integrated luminosity accumulated, additional aging tests are required and taking place for the existing muon detectors. The CSC electronics upgrade is planned to take place during the current Long Shutdown 2 (LS2) and is almost completed. The electronics upgrade of the DT is planned for LS3; currently, a slice test exercise is installed and giving the first results. The production, qualification and installation of GE1/1 detectors has completed in spring 2020, followed by the ongoing commissioning in the CMS experiment. The production of GE2/1 is about to start, while the R&D for ME0 and improved RPC (iRPC) is now in the final phase. The presentation will give an overview of the Muon Spectrometer upgrades, describing the aging studies conducted and the frontend on-chamber electronics developments for the DT and CSC. We will provide an overview on the design of GEM and iRPC detectors, as well as a detailed report on the preliminary results obtained during the production, qualification, installation and commissioning of GE1/1 in CMS.

Speaker: Daniele Fasanella (CERN)

ICHEP_Fasanella.pdf

63 Upgrade of the CMS Cathode Strip Chambers for the HL-LHC

The Large Hadron Collider (LHC) will be upgraded in several phases to significantly expand its physics program, and these upgrades present major challenges to the operations of the CMS cathode-strip-chamber muon system. After the current long shutdown from 2018-2020 (LS2) the accelerator luminosity will be increased to 2 − 3 10^34cm{−2}s{−1}, exceeding the design value of 10^{34}cm^{−2}s^{−1}, allowing the CMS experiment to collect approximately 100 fb^{−1}/year. A subsequent upgrade in 2022-23 will increase the luminosity up to 5 10^{34} cm^{−2}^{s−1}. The CMS muon system must be able to sustain a physics program after the LS2 shutdown that maintains sensitivity to electroweak scale physics and for TeV scale searches similar to what was achieved up to now For the Cathode Strip Chamber (CSC) muon detectors, the electronics will be upgraded to handle the expected higher data rates. The design of the upgraded CSC electronics will be discussed as well as the status of the first phase of the electronics installation. In addition, accelerated irradiation tests are being performed to study the behavior of the CSC electronics under conditions which are nearly an order of magnitude beyond the original design values. Studies have also been performed of chamber gas mixtures to reduce greenhouse-gas impacts. The status of this irradiation campaign and results will be presented.

Speaker: Sven Dildick (Rice Univ.)

ICHEP_2020_CSC_SD_20200728_v5.pdf

ICHEP_2020_CSC_SD_20200728_v6.pdf

64 Upgrade of the ATLAS Muon Drift Tube (MDT) electronics for HL-LHC runs

The ATLAS monitored drift tube (MDT) chambers are the main component of the precision tracking system in the ATLAS muon spectrometer. The MDT system is capable of measuring the sagitta of muon tracks to an accuracy of 60 μm, which corresponds to a momentum accuracy of about 10% at pT=1 TeV. To cope with large amount of data and high event rate expected from the High-Luminosity LHC (HL-LHC) upgrade, ATLAS plans to use the MDT detector at the first-trigger level to improve the muon transverse momentum resolution and reduce the trigger rate. The new MDT trigger and readout system will have an output event rate of 1 MHz and a latency of 6 us at the first-level trigger. A new trigger and readout system has been proposed. Prototypes for two frontend ASICs and a data transmission board have been designed and tested, and detailed simulation of the trigger latency has been performed. We will present the overall design of the trigger and readout system and focus on latest results from different ASIC and board prototypes and system integration.

Speaker: Xueye Hu (University of Michigan (US))

ICHEP_slides_072820_load.pdf

Education and Outreach: Session I - Premiere

Conveners: Miroslav Myska (Czech Technical University (CZ)), Steven Goldfarb (University of Melbourne (AU))

Replay

65 The International Particle Physics Outreach Group - Reaching Across the Globe with Science

The International Particle Physics Outreach Group (IPPOG) is a network of scientists, science educators and communication specialists working across the globe in informal science education and outreach for particle physics. The primary methodology adopted by IPPOG requires the direct involvement of scientists active in current research with education and communication specialists, in order to effectively develop and share best practices in outreach. IPPOG member activities include the International Particle Physics Masterclass programme, International Day of Women and Girls in Science, Worldwide Data Day, International Muon Week and International Cosmic Day organisation, and participation in activities ranging from public talks, festivals, exhibitions, teacher training, student competitions, and open days at local institutions. These independent activities, often carried out in a variety of languages to public with a variety of backgrounds, all serve to gain the public trust and to improve worldwide understanding and support of science. We present our vision of IPPOG as a strategic pillar of particle physics, fundamental research and evidence-based decision-making around the world.

Speaker: Steven Goldfarb (University of Melbourne (AU))

IPPOG-Overview-20200728.pdf

IPPOG-Overview-20200728.pptx

66 Current Status of International Particle Physics Masterclasses

Until recently, the International Masterclasses (IMC) in Particle Physics have been based on hands-on analysis of data from the four big LHC experiments. During the last years there has been a spectacular broadening in the physics scope of particle physics masterclasses, now including measurements with Belle II data, with data from neutrino experiments and a newly proposed masterclass on searches for dark matter. In addition, a particle therapy masterclass has been developed, in order to highlight some of the benefits for society from the technology developed for particle physics research. In parallel to extending the physics scope, IPPOG is making efforts to extend the geographical reach of masterclasses, and it is encouraging to see new institutes and countries joining each year. The IMC programme is the flagship activity of IPPOG, the International Particle Physics Outreach Group.

Speakers: Uta Bilow (Technische Universitaet Dresden (DE)), Kenneth William Cecire (University of Notre Dame (US))

2020_07_ichep_current_status_of_imc_v4.pdf

2020_07_ichep_current_status_of_imc_v4.pptx

67 Netzwerk Teilchenwelt: Coordinated Outreach and Recruitment of Young Talents in Germany

Netzwerk Teilchenwelt is a Germany-wide outreach program comprising 30 universities and research labs. About 150 researchers are involved, bringing cutting edge science into the classroom. 3500 high school students each year take the opportunity to work with original data from HEP experiments in special masterclasses or to study cosmic particles with detectors. On advanced levels, motivated students continue to engage in research and attend workshops at CERN or conduct their research projects. Through a fellow program, highly motivated students are offered early contact with research groups, personal support, and further training. Activities are funded by the German Ministry of Education and Research as an integral part of HEP research. Within the current funding scheme, topics from hadron and nuclear physics are included and links to other projects are created which expand the range of target groups.

Speaker: Uta Bilow (Technische Universitaet Dresden (DE))

praes-ichep-netzwerkteilchenwelt-20200728.pdf

praes-ichep-netzwerkteilchenwelt-20200728.pptx

68 Global Cosmic

Cosmic rays are a unique tool for introducing high-school students to particle physics concepts and methods; their detection and study, with a variety of cosmic ray experiments in schools, is an excellent way to acquaint them with the world of scientific research, motivate and inspire them. Cosmic-ray experiments in schools, using a variety of detector types and sizes, exist in many countries, often as part of networks, and in some cases they also produce scientific results. In order to better exploit the great potential of cosmic-ray experiments for particle physics outreach, IPPOG, the International Particle Physics Outreach Group, started an effort to put such experiments under a common umbrella; a workshop was organised in Rome in 2017 where a whole spectrum of cosmic-ray related activities in schools were represented. Global cosmics – a working group of IPPOG – follows up and reports during IPPOG meetings. Activities such as International Cosmic Day, organised by DESY and Cosmic Ray Week, organized by Quarknet are promoted and strongly encouraged by IPPOG.

Speaker: Nicolas Arnaud (LAL (CNRS/IN2P3 and Université Paris-Sud))

ICHEP2020_GlobalCosmics_v2.pdf

4:50 PM Coffee Break

69 ATLAS Virtual Visits – Take part from anywhere in the world

The Virtual Visit service run by the ATLAS Collaboration has been provided since 2010. The ATLAS Collaboration has used this popular and effective method to bring the excitement of scientific exploration and discovery into classrooms and other public places around the world. The programme, which uses a combination of video conferencing, webcasts, and video recording to communicate with remote audiences has already reached tens of thousands of viewers, with a large number of languages, from tens of countries covering the six populated continents.
We present a summary of the ATLAS Virtual Visit service that is currently in use: the booking system, the video conference that is held from the ATLAS Visit Centre and ATLAS Control Room, the possibility to make virtual tours from the ATLAS cavern, and the new system that is being installed in the ATLAS cavern to provide high-quality underground virtual visits. In addition, we show the reach of the programme over the last few years.

Speaker: Ben Carlson (University of Pittsburgh)

Carlson_VirtualVisitsATLAS_ICHEP_July28_2020.pdf

70 CMS Virtual Visits: engaging audiences worldwide into conversation about cutting edge science

Advances in information and communications technologies (ICTs) have given rise to innovative uses of web-based video tools for global communication, enhancing the impact of large research facilities, including their outreach and education programmes. As an example, the CMS Virtual Visits programme launched by the CMS collaborations at CERN, uses videoconferencing to communicate with schools and other public around the globe.

The goal of the programme is to break down geographical barriers and allow more people to enter the world of science, physics and particle physics. CMS Virtual Visits offer students, teachers and the general public a unique opportunity to explore the experimental site of the CMS detector. Through a web-based videoconference, CMS scientists interact with “remote" visitors in their native language, explain the physics and technology behind the CMS detector, and answer their questions.

Since September 2014, more than 35,000 people, from all of the world, have participated in CMS Virtual Visits. We present an overview of our experience, feedback collected from participants and discuss potential development for the future.

Speaker: Cecilia Uribe Estrada (Puebla)

CMS_VV_ICHEP_2020_C_Uribe_Estrada.pdf

71 Getting the public closer to the experimental facilities: How Virtual Reality helps HEP experiments engage public interest

For many HEP experiments the experimental area is difficult to access for visitors. That makes engaging the public difficult. This is true both for educational purposes and for outreach and media events. The use of the latest technologies in Virtual Reality (VR), Augmented Reality (AR), and 360 degree visualization helps the experiments in getting the public closer to their research. By virtually entering the experimental area the public can visit the different facilities in an immersive and autonomous way; also, by getting closer to the detector, people can get a feeling of the size and the complexity of the experiment itself.
Here we will present the applications based on these technologies developed within the ATLAS Collaboration. We will show how they have been used successfully in presentations to funding agencies and in a number of public events to educate the public about the ATLAS experiment and to generally engage the public in High Energy Physics fundamental research.

Speaker: Ana Peixoto (LIP Laboratorio de Instrumentacao e Fisica Experimental de Part)

ATLASVR_ICHEP2020_AnaPeixoto_28072020.pdf

72 Development of Mixed Reality Software Applications for the ATLAS Experiment

Visualisation plays an important cognitive role in understanding and learning different facilities and processes in high energy physics experiments. It can synthesise Augmented Reality and Virtual Environment to create Mixed Reality Applications with detector descriptions and high-level interactions like gesture or touch controls, easy and minimalistic UI and Lego-like interactions with geometries, for better cognition.
Several Mixed Reality detector display applications can be considered according to user-specific requirements - (ART) - Augmented Reality Table, an application where users will be able to place the detector in the desired location and interact with geometry using a real-time hand recognition system or touch controls and select or grab different components of the detector; (ARD) Augmented Reality Door, where users can place a virtual door in a real-life environment and navigate through the facilities; (LND) Augmented reality landscape, by this application users can place full-sized detectors in real-life environments; (ARB) Augmented Reality Book, users will scan certain images in books or leaflets and see corresponding 3D objects placed on paper.
This paper represents the methods and tools for the creation of the above mentioned Augmented Reality applications.

Speaker: Mariam Pirtskhalava (Georgian Technical University (GE))

Development of Mixed Reality Software Applications for ATLAS Experiment.pdf

Development of Mixed Reality Software Applications for ATLAS Experiment.pptx

73 The ATLAS public website - Evolution to Drupal 8

Four years after the deployment of the ATLAS public website using the Drupal 7 content management system, the ATLAS Education & Outreach group is in the process of migrating to the new CERN Drupal 8 infrastructure. We present lessons learned from the development, usage and evolution of the original web site, and how the choice of technology helped to shape and reinforce our communication strategy. We then discuss tactics for the migration to Drupal 8, including our choice to use the CERN Override theme. This theme was developed by the CERN web team to support clients like ATLAS to develop web sites in the relatively complex and non-intuitive environment of Drupal. Furthermore, CERN has encouraged usage of this theme to mitigate support and ease future migration. We present the effects this choice has on the design, implementation, operation and maintenance of the new site.

Speaker: Meirin Oan Evans (University of Sussex (GB))

Meirin_ICHEP_web.pdf

Meirin_ICHEP_web.pptx

Heavy Ions: Session I - Premiere

Conveners: Dr Barbara Antonina Trzeciak (Czech Technical University in Prague), Dennis Perepelitsa (University of Colorado Boulder)

Replay

74 Measurement of electroweak-boson production in p-Pb and Pb-Pb collisions with ALICE at the LHC

W and Z bosons are clean probes of the initial-state effects in hadronic collisions, being formed in the hard scatterings taking place in the initial stages, and being insensitive to the presence of any strongly-interacting medium. This is especially true at the LHC energies, where having a clear picture of the initial state is mandatory to properly interpret the later stages characterising the complex evolution of p-Pb and Pb-Pb collisions. In particular, measurement of W and Z boson production in p-Pb and Pb-Pb collisions at the LHC provides constraints on the nPDFs of the (anti-)quarks in a phase-space region that is poorly constrained by previous experiments.

ALICE measures W and Z boson production in the muonic decay channels at forward rapidities ($2.5 < y_\mathrm{lab} < ~4$). In this contribution, recent measurements on the Z and W boson production in p-Pb and Pb-Pb collisions at the center-of-mass energies per nucleon pair of $\sqrt{s_\mathrm{NN}} = 8.16$ and 5.02 TeV, respectively, are presented. Results, including invariant production yield and nuclear modification factors as a function of rapidity and collision centrality, are compared to calculations obtained with or without including nuclear modifications of the PDFs, as well as to results obtained by other LHC experiments.

Speaker: Mingrui Zhao (China Institute of Atomic Energy (CN))

slide_EWBosons_v4.pdf

75 Quarkonia photo-production and Z production in heavy ion collisions

Vector meson photo-production in ultra-peripheral Pb-Pb collisions is sensitive to nuclear parton distribution functions, and probe models of vector meson production in nuclear interactions with strong electromagnetic fields. In pPb collisions, measurements of the Z production in the forward (pPb) and backward (Pbp) configurations are sensitive to the nPDFs in different kinematic domains, such that both probes enable complementary studies of the structure of the nucleus. In this talk, we present the latest results on charmonium production in PbPb ultra-peripheral collisions and on Z production in pPb and Pbp collisions at LHCb.

Speaker: Giulia Manca (Universita` degli studi di Cagliari and INFN, Cagliari, IT)

Manca_ICHEP2020_NoBackup.pdf

76 Electroweak probes in heavy-ion collisions with ATLAS

Electroweak bosons produced in lead-lead (Pb+Pb) collisions are an excellent tool to constrain initial-state effects which affect the rates of hard-scattering processes in nucleus-nucleus interactions. The production yields of massive electroweak bosons, observed via their leptonic decay channels, offer a high-precision test of the binary collision scaling expected in Pb+Pb and a way to quantify nuclear modifications of the parton distribution functions (PDFs). The large samples of Pb+Pb data at $\sqrt{s_{\mathrm{NN}}}$ = 5.02 TeV collected by the ATLAS experiment in 2015, and the corresponding high-statistics $pp$ data at the same collision energy used as a baseline, allow for a detailed experimental study of these phenomena and comparisons to predictions from a variety of theoretical calculations. This talk presents the latest ATLAS results on electroweak boson production, including updated results on Z production and high-precision W boson results in Pb+Pb collisions. Inclusive production of prompt photons in proton-lead~($p$+Pb) collisions at $\sqrt{s_{\mathrm{NN}}}$ = 8.16 TeV is also covered. Various predictions of nuclear modifications to PDFs are discussed.

Speaker: Jakub Andrzej Kremer

ICHEP2020-ATLAS-HIEWBosons.pdf

77 Considerations on the suppression of charged particle production in high energy heavy ion collisions

Results from RHIC for Au-Au and from LHC for Pb-Pb collisions are compiled in terms of $R_{AA}$, $R_{CP}$ and ratio of the $p_T$ spectra, normalized with the corresponding $dN_{ch}/d\eta$, for each centrality to the most peripheral one ($R^N_{CP}$). The studies are focused on the $p_T$ range in the region of maximum suppression evidenced in the experiment. The $R_{CP}$ for 4 GeV/c < $p_T$ < 6 GeV/c as a function of $\sqrt{s_{NN}}$ evidences a suppression enhancement from $\sqrt{s_{NN}}$ = 39 GeV up to 200 GeV after which a saturation sets in up to the highest energy of $\sqrt{s_{NN}}$ =5.02 TeV. For collision energies from 200 GeV (Au-Au) up to 5.02 TeV (Pb-Pb), within the error bars, a good scaling of $R_{AA}$ as a function of <$N_{part}$> is evidenced. This scaling improves for $R_{AA}$, when only the core contribution is considered. $R^N_{CP}$ evidences the same saturation starting from 200 GeV collision energy and a very good scaling as a function of <$N_{part}$> for $\sqrt{s_{NN}}$ =200 GeV (Au-Au) and for $\sqrt{s_{NN}}$ =2.76 TeV and $\sqrt{s_{NN}}$ =5.02 TeV (Pb-Pb). A comparison in terms of Bjorken energy density times formation time ($\varepsilon_{Bj}\cdot\tau$) and particle density per unit of rapidity and overlapping area ($(dN/dy)/S_{\perp}$) is presented.

Speaker: Mihai Petrovici (Horia Hulubei National Institute of Physics and Nuclear Enginee)

mp_ICEP-2020.pdf

78 Jets and medium evolution in Pb-Pb collisions at the LHC energies from the EPOS initial state

We present the results for PbPb collisions at 2.76 TeV LHC energy from a parton shower integrated with a hydrodynamic evolution. The initial hard (jet) partons are produced along with soft partons in the initial state EPOS approach. The EPOS initial state typically contains multiple hard scatterings in each event. The soft partons melt into a thermalized medium, which is described with a 3 dimensional event-by-event viscous hydrodynamic approach. The jet partons then propagate in the hydrodynamically expanding medium. The total jet energy gets progressively “degraded” according to a state-of-the-art microscopic radiative energy loss Monte Carlo for the low-virtuality jet partons. The full evolution proceeds in a concurrent mode, without separating hydrodynamic and jet parts. We discuss two features of PbPb collision:
1) A jet overlap effect [1] which emerges due to multiple hard parton production in each heavy-ion collision event
2) Jet energy loss in the medium and its modification due to the LPM effect.

[1] Iu. Karpenko, J. Aichelin, P. Gossiaux, M. Rohrmoser, and K. Werner,
Phys. Rev. C 101, 014905 (2020)

Speaker: Dr Iurii Karpenko (CTU Prague)

ICHEP2020-karpenko.pdf

79 Jet production and fragmentation at colliders

Fragmentation (or in general, hadronization) is the transition from a colored and energetic parton to a colorless hadron is a rich and dynamical process in QCD quantified by the fragmentation function. Fast moving hadrons (or jets) are produced by the fragmentation of colored quarks or gluons that are produced during hard collisions at short distances. The determination of a characteristic time scale for the color neutralization would shed light on the properties of color confinement and help answer the question: how hadrons emerge out of quarks and gluons?

Since the earliest days of collider physics, jets have been an important tool in the exploration of QCD and have provided important discoveries and insights, in all colliding systems, including e-e, e-p hadron-hadron, and nucleus-nucleus. With the advances in experimental techniques, and corresponding theoretical progress over time, jets have become precision tools for studying the partonic structure of matter.
Starting at the Relativistic Heavy Ion Collider (RHIC) at BNL, a suppression by a factor of five of the yield of high $p_\mathrm{T}$ hadrons in Au-Au collisions, compared to proton-proton collision at the same energy was observed and called “jet quenching”. The same phenomenon was confirmed by the heavy-ion program at the CERN’s Large Hadron Collider (LHC) where the jet quenching phenomenon was observed at much greater collision energies that became accessible, allowing new and more detailed characterization of the quark-gluon plasma. While interacting with the medium, a modification of the jet structure and a redistribution of jet energy as well as a modification of their fragmentation pattern is expected.
Jets in (SI)DIS are also guaranteed to contribute at the Electron-Ion Collider (EIC) to a variety of key electron-nucleus and electron-hadron physics topics in particular the study of hadronization, aiming to shed light on the nature of color neutralization and confinement.

A selection of results (not focussed on a particular experiment) on jet physics will be discussed and compared to theoretical calculations. The measurements that will be discussed may include $p_\mathrm{T}$-differential jet production cross sections or detailed studies of the parton shower through observables like the jet mass, jet fragmentation functions or jet substructure observables. Well defined jet shapes observables can also provide complementary information on the fragmentation process.

Speaker: Alexandre Shabetai (Centre National de la Recherche Scientifique (FR))

ichep2020_shabetai_web..pdf

5:54 PM Coffee break

80 Jet Measurements in Heavy Ion Collisions with the ATLAS Experiment

Jets are an important tool to study the hot, dense matter produced in Pb+Pb collisions at the LHC. They are produced at the early stages of the collisions and are expected to be modified as they propagate through the hot and dense medium. This leads to energy loss as well as modification of the jet structure. This talk presents the latest jet measurements from Run 2 heavy-ion collisions data from ATLAS. The results shown in this talk include measurements of the angular distribution of charged particles around the jet axis, measurements of the flavor-dependence of energy loss via b-jets and jets associated with photons and Z bosons, and measurements of the jet internal structure characterized by the transverse momentum scale for the hardest splitting. Furthermore, the latest results on the dijet momentum balance in $pp$, Xe+Xe, and Pb+Pb collisions will be presented. The talk will also show a measurement of the single jet yields as a function of the azimuthal angle with respect to the event plane in Pb+Pb collisions. The data are compared to state of the art theoretical models and provide important information to understand the strength and mechanism of the jet quenching.

Speaker: Helena Santos (LIP - Lisbon)

ICHEP2020_HSantos.pdf

81 Universal features of the medium-induced gluon cascade and jet quenching in expanding media

We present a study of the impact of the expansion of deconfined medium on single-gluon emission spectra and the jet suppression factor ($𝑄_{𝐴𝐴}$) within the BDMPS-Z formalism. These quantities are calculated for three types of media (static medium, exponentially decaying medium and Bjorken expanding medium). The distribution of medium-induced gluons and the jet $𝑄_{𝐴𝐴}$ are calculated using the evaluation of in-medium evolution with splitting kernels derived from the gluon emission spectra. A universal behavior of splitting kernels is derived for low-𝑥 and high-𝑥 regimes in the asymptote of large times and its impact on the resulting jet $𝑄_{𝐴𝐴}$ is discussed. For the full phase-space of the radiation, the scaling of jet $𝑄_{𝐴𝐴}$ with an effective quenching parameter is derived. The importance of the medium expansion for precise modeling of jet quenching phenomena as well as steps towards generalizing the results to other jet quenching observables are discussed.

Speaker: Dr Souvik Priyam Adhya (Institute of Particle and Nuclear Physics Faculty of Mathematics and Physics, Charles University)

ichep2020_spa_v1.pdf

82 Overview of the latest jet physics results from ALICE

Collisions of ultra-relativistic heavy ions are used to create strongly interacting matter in the regime of high-energy densities and temperatures. Under these conditions color confinement of quarks and gluons in hadrons breaks down and a new state of matter called Quark-Gluon Plasma is formed. Properties of this medium can be inferred based on observed modifications of produced jets. Recently, new tools were developed to study jet properties more differentially. These observables are based on jet-shape and jet-substructure measurements or employ hadron-jet correlations. The talk will review the latest results from these jet analyses performed by the ALICE Collaboration in pp and Pb-Pb collisions.

Speaker: James Mulligan (University of California, Berkeley (US))

20200728_Mulligan_ICHEP_animated.pdf

83 Jet quenching and effects of non-Gaussian transverse-momentum broadening on di-jet observables

I am going to report on recent study, at a qualitative level, production of jet pairs in ultrarelativistic nuclear collisions within a framework combining High Energy Factorisation (HEF) and in-medium propagation of jet particles that takes into account stochastic transverse forces as well as medium-induced radiation. We find that the resulting di-jet observables feature the behaviour deviating from that of jet-pairs which undergo transverse-momentum broadening following the Gaussian distribution. The result follows from application of only recently solved by Kutak, Straka, Placzek evolution equation formulated by Blaizot, Dominguez, Iancu, Mehtar-Tani, Dominguez.
The application of recently solved equation allows for studies of interplay of energy loss via branchings and rescattering leading to broadening therefore in the end to more detailed study of structure of jets in Heavy Ion Collisions.

Speaker: Krzysztof Kutak (Instytut Fizyki Jadrowej Polskiej Akademii Nauk)

kutakHI2.pdf

84 Hard probes in heavy ion collisions with CMS

We review recent CMS results on hard probes of heavy ion collisions, including jet and electroweak boson production.

Speaker: Xiao Wang (Univ. of Illinois at Chicago)

ICHEP_Xiao_hardprobes_v2.pdf

85 Precision Jet/Event Substructure Using Collinear Drop

I will present a new class of jet/event substructure observable called collinear drop and its use in the search for novel signatures of jet modifications and medium responses. It is demonstrated using Monte Carlo simulations generated with Jewel how underlying jet-medium interactions can be systematically examined using collinear-drop observables. Studies using LEP open data and applications to Electron Ion Collider will be discussed. Analytic insights on the modifications of such observables will also be given using soft-collinear effective theory with Glauber gluon interactions.

Speaker: Dr Yang-Ting Chien (Stony Brook University)

ICHEP_Chien.pdf

Neutrino Physics: Session I - Premiere

Conveners: Thomas Schwetz, Ryan Patterson (California Institute of Technology)

Replay

86 Global fits to neutrino masses and mixings

In this talk, I will describe the updated status of global analyses to neutrino oscillation data in the three-flavor framework, with an emphasis on the recent hints in favor of normal mass ordering and maximal CP violation. I will focus on the current knowledge of the oscillation parameters as well as on the improvements that can be expected in the near future.

Speaker: Dr Mariam Tórtola (IFIC (CSIC/Universitat de València))

MTortola-ICHEP2020.pdf

87 Direct comparison of sterile neutrino constraints from cosmological data, electron neutrino disappearance data and muon neutrino to electron neutrino appearance data in a 3+1 model

We present a quantitative, direct comparison of constraints on sterile neutrinos derived from neutrino oscillation experiments and from Planck data, interpreted assuming standard cosmological evolution. We extend a $1+1$ model, which is used to compare exclusions contours at the 95% CL derived from Planck data to those from $\nu_{e}$-disappearance measurements, to a $3+1$ model. This allows us to compare the Planck constraints with those obtained through $\nu_{\mu}\rightarrow\nu_{e}$ appearance searches, which are sensitive to more than one active-sterile mixing angle. We find that the cosmological data fully exclude the allowed regions published by the LSND, MiniBooNE and Neutrino-4 collaborations, and those from the gallium and rector anomalies, at the 95% CL. Compared to the exclusion regions from the Daya Bay $\nu_{e}$-disappearance search, the Planck data are more strongly excluding above $|\Delta m^{2}_{41}|\approx 0.1\,\mathrm{eV}^{2}$ and $m_\mathrm{eff}^\mathrm{sterile}\approx 0.2\,\mathrm{eV}$, with the Daya Bay exclusion being stronger below these values. Compared to the combined Daya Bay/Bugey/MINOS exclusion region on $\nu_{\mu}\rightarrow\nu_{e}$ appearance, the Planck data is more strongly excluding above $\Delta m^{2}_{41}\approx 5\times 10^{-2}\,\mathrm{eV}^{2}$, with the exclusion strengths of the Planck data and the Daya Bay/Bugey/MINOS combination becoming comparable below this value.

Speaker: Justin Evans (University of Manchester (UK))

2020-07-ICHEP.pdf

2020-07-ICHEP.ppt

88 Neutrino oscillations, flavor theories and dark matter

After a brief review of the status of neutrino oscillation
experiments I discuss some recent results on flavor extensions of the
standard model and their possible implications for dark matter.

Speaker: Jose Valle

valle-ichep2020web.pdf

Valle-neutrino-zoom_0.mp4

Valle-neutrino-zoom_0.mp4

89 Extraction of the optical potential for final state nucleons and $\Delta$ resonances for electron and neutrino scattering on nuclear targets

Precise modeling of neutrino (and electron) interactions on nuclear targets is essential for neutrino oscillations experiments. The modeling the energy of final state leptons and nucleons in quasielastic scattering on bound nucleons requires knowledge of both the removal energy of the bound nucleon as well as the Coulomb and nuclear optical potentials for the final state nucleon in the field of the spectator (A-1) nucleus. We compare the values of the optical potential for final state protons extracted from electron scattering data on nuclear targets in the quasielastic region to the extracted values of the optical potential for $\Delta$ resonances in the final state. This is the first measurement of the optical potential for the $\Delta$ resonance. We find that the optical potential for a $\Delta$ resonance in the final state is larger than the optical potential for a final state proton.

Speaker: Arie Bodek (University of Rochester (US))

Bodek-Cai2020_Article_EPJC.pdf

Bodek-Cai-optical-talk- ICHEP.pdf

90 Constraints on nonstandard interactions and the neutron radius from coherent elastic neutrino-nucleus scattering experiments

There are expectations for achieving new measurements of the coherent elastic neutrino-nucleus scattering (CENNS) by
using electron antineutrinos from reactor experiments and through muon (electron) neutrinos from spallation neutrino
sources (SNS). The first scenario takes into account very low energy neutrinos while the second one includes
relatively higher energy neutrinos. These measurements would allow improve our knowledge about standard and beyond
Standard Model physics, for instance as regards the nuclear radius and nonstandard interactions, respectively. In
this talk we will show constraints on the neutron radius and nonstandard parameters obtained from CENNS processes in
experiments of both reactor neutrinos and SNS. We will also display that a combination of several experiments could
give rise to more robust constraints on the parameters mentioned above.

Speaker: Alexander Parada Valencia (Universidad Santiago de Cali)

Future sensitivity to NSI and neutron radius_ICHEP_2020.pdf

91 Neutrino Portals to Dark Matter

We explore the possibility that dark matter interactions with Standard Model particles are dominated by interactions with neutrinos. We examine whether it is possible to construct such a scenario in a gauge invariant manner. We first study the coupling of dark matter to the full lepton doublet and confirm that this generally leads to the dark matter phenomenology being dominated by interactions with charged leptons. We then explore two different implementations of the neutrino portal in which neutrinos mix with a Standard Model singlet fermion that interacts directly with dark matter through either a scalar or vector mediator. In the latter cases we find that the neutrino interactions can dominate the dark matter phenomenology. Present neutrino detectors can probe dark matter annihilations into neutrinos and already set the strongest constraints on these realisations. Future experiments such as Hyper-Kamiokande, MEMPHYS, DUNE, or DARWIN could allow to probe dark matter-neutrino cross sections down to the value required to obtain the correct thermal relic abundance.

Speaker: Salvador Rosauro Alcaraz (Universidad Autónoma de Madrid)

NPDM.pdf

92 Astrophysical Visible Neutrino Decay

Neutrino decay modifies neutrino propagation in a unique way; not only is there flavor changing as there is in neutrino oscillations, there is also energy transport from initial to final neutrinos. The most sensitive direct probe of neutrino decay is currently IceCube which can measure the energy and flavor of neutrinos traveling over extragalactic distances. For the first time we calculate the flavor transition probability for the cases of visible and invisible neutrino decay, including the effects of the expansion of the universe, and consider the implications for IceCube. As an example, we demonstrate how neutrino decay addresses a tension in the IceCube data.

Speaker: Dr Peter Denton (Brookhaven National Laboratory)

Seminar.pdf

5:15 PM Coffee break

93 Neutrino-Nucleus Interaction Physics with the Most Recent MINERvA Low-Energy Beam Data

MINERvA at FNAL is an experiment dedicated to the study of neutrino-nucleus interaction physics. Its goal is to provide constraints on nuclear effects that are crucial for present and future neutrino oscillation measurements, and to illustrate the interplay between hadronic and nuclear physics at the few-GeV regime. As the analysis of the Low-Energy data---the beam flux peaks at about 3 GeV with most of the rate between 1-6 GeV---is coming to a conclusion, nuclear effects are shown to be a complex phenomenon which challenges many of the popular theoretical descriptions. In this talk, a summary of the most recent MINERvA Low-Energy Beam results will be presented, alongside with discussions on their implication for future neutrino oscillation measurements.

Speaker: Dr Xianguo Lu (University of Oxford)

20200728_ICHEP_xlu.pdf

94 Review of MINERvA's Medium Energy Neutrino Physics Program

The MINERvA experiment completed its physics run using the 6-GeV,on-axis NuMI ME beam at Fermilab. The experiment received a total of 12E20 protons on target in both neutrino and antineutrino mode running. This allows MINERvA a new level of statistical precision in neutrino interaction measurements with the ability to measure multi-dimensional differential cross sections. In order to make the most of this jump in statistics, a new level of precision in flux prediction has also been required. This talk will cover MINERvA’s Medium Energy (ME) physics program, including the new kinematic regimes that are now accessible, and will also discuss the exceptional precision reached in flux determination.

Speaker: Heidi Marie Schellman (Oregon State University (US))

CCQEICHEP2020_v05.pdf

CCQEICHEP2020_v05.pptx

95 Recent Cross-section Measurements from MicroBooNE

MicroBooNE is a liquid argon time projection chamber in the Booster Neutrino Beam at Fermilab. The large event rate and 3 mm wire spacing of the detector provide high-statistics, precise-resolution imaging of neutrino interactions leading to low-threshold, high-efficiency event reconstruction with full angular coverage. As such, MicroBooNE is an ideal place to probe neutrino-argon interactions in the hundreds-of-MeV to few-GeV energy range, and to study the impact of nuclear effects through detailed measurements of hadronic final states. This will be the subject of this talk.

Speaker: Raquel Castillo Fernandez (FNAL)

RaquelCastillo_ICHEP2020.pdf

96 Neutral Current Pi0 Rate Measurement with the MicroBooNE Detector

The talk presents the first measurement of Neutral Current (NC) $\pi^0$ production on argon in a sub-GeV neutrino beam with the MicroBooNE liquid argon time projection chamber (LArTPC) detector. The analysis qualifies data to Monte Carlo agreement in several reconstructed kinematic variables, and investigates contributions from coherent and non-coherent NC $\pi^0$ production processes independently. Those are the dominant contributing backgrounds to MicroBooNE’s search for low-energy excess single-photon events, for two separate exclusive final state samples. A data-driven determination of the NC $\pi^0$ rate and coherent fraction is critical for constraining backgrounds to MicroBooNE’s single-photon search.

Speaker: Mark Ross-Lonergan (Columbia University)

markrosslonergan_ICHEP2020_NCPi0Measurement_Microboone_v2.1.pdf

97 Charged-Current Electron Neutrino measurement with the MicroBooNE detector

MicroBooNE is the first phase of Fermilab's Short Baseline Neutrino (SBN) Liquid Argon Time Projection Chamber (LArTPC) programme.
This talk outlays the first characterisation of electron neutrinos in a muon neutrino beam with the LArTPC detector technology. The Booster Neutrino Beam has an energy peaking around 1 GeV and an electron content of approximately 0.5%. The analysis investigates electrons produced in charged-current electron neutrino interactions. The kinematics of the electrons are measured along with comparisons to simulation. Most of the systematic uncertainties are constrained using a data-driven sample of charged-current muon neutrino events. The measurement of electron neutrinos originating from the Booster Neutrino Beam is a crucial component to understand the nature of the observed excess of low energy electromagnetic-like events at MiniBooNE.

Speaker: Dr Wouter Van De Pontseele (Harvard University)

Wouter_MicroBooNE_nue.pdf

Wouter_MicroBooNE_nue_small.pdf

98 Recent Cross-section Results from the T2K Experiment

One of the largest systematic uncertainties affecting neutrino oscillation measurement comes from present limited knowledge of (anti-)neutrino-nucleus interactions. Neutrino scattering understanding is crucial for the interpretation of neutrino oscillation since it affects background estimation and neutrino energy reconstruction. Thus, precise (anti-)neutrino-nucleus cross section measurements are vital for the present and future long-baseline neutrino oscillation experiments. The T2K long-baseline neutrino oscillation experiment, in addition to its contributions to neutrino oscillation measurement, has a wide program of neutrino interaction cross-section measurements using its near detector complex. With multiple targets (carbon, water, argon, iron), and with on- and off-axis detectors which sample different neutrino spectra from the same beamline, T2K is able to investigate atomic number and energy dependent behavior in a single experiment. In this talk an overview of the T2K neutrino cross sections, focusing on the latest results is presented.

Speaker: Dr Ka Ming Tsui (University of Liverpool)

t2k_xsec_ichep2020_kmtsui_final.pdf

99 Neutrino Oscillations Results from the T2K Experiment

The T2K experiment probes the masses and mixing of neutrinos through measurements of neutrino oscillations. A beam of muon neutrinos or muon antineutrinos is generated at the J-PARC proton accelerator on the east coast of Japan, and the beam’s composition is measured 295 km away in the Super-Kamiokande detector. The transition of muon neutrinos and antineutrinos to other flavors and the appearance of electron neutrinos and antineutrinos are governed by neutrino mixing and mass parameters, including the phase $\delta_{cp}$, which determines the amount of CP violation in neutrino mixing. Previous measurements from T2K have shown a strong constraint on $\delta_{cp}$ with the exclusion of a significant fraction of $\delta_{cp}$ values at 3$\sigma$ confidence. Here, we present the latest results from T2K with data collected through 2020 and the prospects for more sensitive measurements by T2K in the future.

Speaker: Laura-Iuliana Munteanu (Université Paris-Saclay (FR))

ICHEP2020T2KResults_final.pdf

100 The T2K ND280 Upgrade

In view of the J-PARC program of upgrades of the beam intensity, the T2K collaboration is preparing towards an increase of the exposure aimed at establishing leptonic CP violation at 3 $\sigma$ level for a significant fraction of the possible $\delta_{CP}$ values. To reach this goal, an upgrade of the T2K near detector ND280 will be installed at J-PARC in 2021, with the aim of reducing the overall statistical and systematic uncertainties at the appropriate level of better than 4\%.
We have developed an innovative concept for this neutrino detection system, comprising the totally active Super-Fine-Grained-Detector (SuperFGD), two High Angle TPC (HA-TPC) and six TOF planes.
The SuperFGD, a highly segmented scintillator detector, acting as a fully active target for the neutrino interactions, is a novel device with dimensions of ~2x1.8x0.6 m3 and a total mass of about 2 tons. It consists of about 2 millions of small scintillator cubes each of 1 cm3. Each cube is covered by a chemical reflector. The signal readout from each cube is provided by wavelength shifting fibers inserted connected to micro-pixel avalanche photodiodes MPPCs. The total number of channels will be ~60,000. We have demonstrated that this detector, providing three 2D projections, has excellent PID, timing and tracking performance, including a $4 \pi$ angular acceptance, especially important for short proton and pion tracks.
The HA-TPC will be used for 3D track reconstruction, momentum measurement and particle identification. These TPC, with overall dimensions of 2x2x0.8 m3, will be equipped with 32 resistive Micromegas. The thin field cage (3 cm thickness, 4% rad. length) will be realized with laminated panels of Aramid and honeycomb covered with a kapton foil with copper strips. The 34x42 cm2 resistive bulk Micromegas will use a 500 kOhm/square DLC foil to spread the charge over the pad plane, each pad being appr. 1 cm2. The front-end cards, based on the AFTER chip, will be mounted on the back of the Micromegas and parallel to its plane.
The time-of-flight (TOF) detector will allow to reject events generated in the passive areas of the detector and improve particle identification. The TOF will consist of 6 planes with about 5 m2 surface area surrounding the SuperFGD and the TPCs. Each plane will be assembled with 2.2 m long cast plastic scintillator bars with light collected by arrays of large-area MPPCs from two ends. The time resolution at the bar centre is 150 ps.
In this talk we will report on the design of these detectors, their performance, the results of the test beam and the plan for the construction.

Speaker: Davide Sgalaberna (ETH Zurich (CH))

ND280 upgrade ICHEP2020 - final.pdf

101 Latest Oscillation Results Combining Neutrino and Antineutrino Data from the NOvA Experiment

The NOvA experiment is a long-baseline neutrino oscillation experiment that uses the NuMI beam from Fermilab to detect both electron and muon flavored neutrinos in a Near Detector, located at Fermilab, and a Far Detector, located at Ash River, Minnesota. NOvA's primary physics goals include precision measurements of neutrino oscillation parameters, such as $\theta_{23}$ and the atmospheric mass-squared splitting, along with probes of the mass hierarchy and the CP violating phase. This talk will present the latest NOvA results using a combined neutrino and anti-neutrino dataset based on a beam exposure of approximately $13 \times 10^{20}$ protons-on-target in each dataset.

Speaker: Michael Baird (University of Virginia)

nova_A20_summary_ICHEP-2020-07-28.pdf

102 The NOvA Test Beam Program

NOvA is a long-baseline oscillation neutrino experiment designed to study and measure a wide range of important topics for neutrino physics such as the neutrino mixing parameters, the neutrino mass hierarchy, and CP violation in the lepton sector. The NOvA Test Beam experiment uses a scaled-down detector of 30 tons to analyze tagged beamline particles. A new tertiary beamline deployed at Fermilab can select and identify electrons, muons, pions,kaons and protons with energies from 0.3 to 2 GeV. Using these data, the Test Beam program will provide NOvA with a better understanding of the largest systematic uncertainties impacting NOvA’s analyses, which include the detector response, calibration, and hadronic and electromagnetic energy resolution. In this talk, I will present the status
and future plans for the NOvA Test beam program, along with preliminary results.

Speaker: Michael Wallbank

TheNOvATestBeamProgram.pdf

103 The COHERENT Experiment at the Spallation Neutron Source

The pioneering experiments by the COHERENT collaboration at the Spallation Neutron Source (SNS) at the Oak Ridge National Laboratory yielded the first observations of coherent elastic neutrino nuclear scattering (CEvNS). The first observation on argon was recently presented and demonstrates the potential of this new neutrino laboratory to exploit CEvNS as a new probe of physics topics including electromagnetic properties, searches for physics beyond the standard model, and nuclear form factors. COHERENT is deploying two new instruments to measure CEvNS on sodium and germanium nuclei and is pursuing multiple ton-scale detectors to improve precision and accuracy. The SNS is also ideally suited for a broader set of high-precision neutrino physics measurements and dark matter searches because of the accelerator's intensity, pulsed-structure, and proton beam energy. The experimental features of this new capability as well as the recent results of our operating detectors will be presented.

Speaker: Alexey Konovalov

ICHEP_2020_Konovalov.pdf

104 Sterile neutrino searches with the ICARUS detector

The ICARUS collaboration employed the 760-ton T600 detector in a successful three-year physics run at the underground LNGS laboratories studying neutrino oscillations with the CNGS neutrino beam from CERN, and searching for atmospheric neutrino interactions. ICARUS performed a sensitive search for LSND-like anomalous $\nu_e$ appearance in the CNGS beam, which contributed to the constraints on the allowed parameters to a narrow region around 1 eV$^2$, where all the experimental results can be coherently accommodated at 90% C.L. After a significant overhauling at CERN, the T600 detector has now been placed in its experimental hall at Fermilab where installation activities are in progress. It will be soon exposed to the Booster Neutrino Beam to search for a sterile neutrino within the Short Baseline Neutrino (SBN) program, devoted to definitively clarify the open questions of the presently observed neutrino anomalies. The proposed contribution will address ICARUS achievements, its status and plans for the new run at Fermilab and the ongoing developments of the analysis tools needed to fulfill its physics program.

Speaker: Christian Farnese (Universita e INFN, Padova (IT))

ICHEP2020_Farnese.pdf

105 Search for a Low-energy Excess with MicroBooNE

MicroBooNE is a neutrino experiment based at Fermilab that utilizes a liquid argon time projection chamber (LArTPC) located on-axis in the Booster Neutrino Beam (BNB) at Fermilab. One of the experiment’s main goals is to search for excess low-energy electromagnetic-like events as seen by the MiniBooNE experiment, located just downstream of MicroBooNE in the BNB. This talk will present MicroBooNE's low-energy excess search, including targeted searches for both single-photon-like and single-electron-like events.

Speaker: David Caratelli (Fermi National Accelerator Laboratory)

Caratelli_ICHEP_MicroBooNE_LowEnergyExcess.pdf

106 Search for heavy neutral lepton production at the NA62 experiment

Searches for heavy neutral lepton production in K+ --> e+N and K+ --> mu+N decays using the data set collected by the NA62 experiment at CERN in 2016-18 are presented. Upper limits on the elements of the extended neutrino mixing matrix $|U_{e4}|^2$ and $|U_{\mu4}|^2$ are established at the levels of $10^{-9}$ and $10^{-8}$, respectively, improving on the earlier searches for heavy neutral lepton production and decays in the kinematically accessible mass range.

Speaker: Evgueni Goudzovski

goudzovski_280720.pdf

Operation, Performance and Upgrade of Present Detectors: Session I - Premiere

Conveners: Sowjanya Gollapinni (Los Alamos National Laboratory (US)), Stefania Beole (Universita e INFN Torino (IT)), Jiri Kroll (Czech Academy of Sciences (CZ))

Replay

107 THE LIGO-VIRGO OBSERVATION RUN 3 (APRIL 2019 – APRIL 2020)

Observation Run 3 (O3) is the longest period of data taking for the two Advanced LIGO detectors and the Advanced Virgo detector to date. From April 1st, 2019 to April 30th, 2020, the instruments accumulated 12 months of data, with a 1-month commissioning break in October 2019. In this talk, I will review the performance of the three detectors both separately and within the global network of ground-based gravitational-wave interferometric detectors: sensitivity, duty cycle, noise stability and variations. I will briefly describe the O3 public alerts and the first published results of this run. To conclude, I will summarize the plans of the two collaborations for the coming years: alternatively upgrade phases and data taking periods with improved performance.

Speaker: Dr Nicolas Arnaud (LAL (CNRS/IN2P3 and Université Paris-Sud))

ICHEP2020_O3_v2.pdf

108 The AugerPrime Upgrade of the Pierre Auger Observatory.

To answer many questions still open in the field of Ultra-High-Energy Cosmic Rays, the Pierre Auger Collaboration started a significant upgrade of the Observatory, called AugerPrime.

The main goal of the upgrade is to improve the mass composition sensitivity of the surface detector on a shower-to-shower basis, in order to explore the cosmic ray composition at energies above 10$^{19}$eV. At energies unexplored by terrestrial accelerators, it will be possible to study the properties of multi-particle production and to search for new or unexpected changes of hadronic interactions. Moreover, in the region of the suppression of the cosmic ray flux, charged particle astronomy will benefit from the knowledge of the fraction of light primaries for composition-selected anisotropy searches.

After a discussion of the motivations for upgrading the Pierre Auger Observatory, a description of the detector upgrade will be provided, together with an evaluation of the expected performance and the improved physics sensitivity. Finally the first data collected will be presented.

Speaker: Gabriella Cataldi (INFN, Sezione di Lecce, Lecce, Italy)

Cataldi_AugerPrime_ICHEP_v1.pdf

109 The Mu2e Electromagnetic Calorimeter

The “muon-to-electron conversion” (Mu2e) experiment at Fermilab will search for the Charged Lepton Flavour Violating neutrino-less coherent conversion /mu^-N(A,Z) -> e-N(A,Z) of a negative muon into an electron in the field of an aluminum nucleus. The observation of such physics process would be the unambiguous evidence of the existence of physics beyond the Standard Model. The Mu2e detector is composed of a tracker and an electromagnetic calorimeter and an external veto for cosmic rays. The calorimeter plays an important role in providing excellent particle identification capabilities, a fast online trigger filter and aiding track reconstruction. The calorimeter requirements are to provide a large acceptance for ~100 MeV electrons and reach: 1) a time resolution better than 0.5 ns; 2) an energy resolution O(10%); 3) a position resolution of 1 cm. The detector has been designed as a state-of-the-art crystal calorimeter and employs pure Cesium Iodide (CsI) crystals and UV-extended Silicon PhotoMultipliers (SiPMs) readout by fast analog electronics with a digitization at 200 Msps. A design consisting of two disks, each one made of 674 crystals readout by two large area 2x3 arrays of SiPMs of 6x6 mm^2 area can largely satisfy Mu2e requirements. The detector has to satisfy many other demanding requests, such as keeping the required performance in an extremely hostile environment with 1 tesla axial magnetic field, high radiation level and 10^-4 Torr vacuum. We have verified with a campaign of test beams that the CsI crystals will withstand the expected dose and fluence with a small light yield loss and the SiPMs will function under the expected neutron irradiation when cooled to 0 C. This requires a good engineering design of the calorimeter mechanics and its cooling system, in terms of performance as well as reliability.
A large scale detector prototype has been constructed and tested at the beam test facility in Frascati. It consists of 51 pre-production crystals readout by a 102 SiPMs. All the tests and progresses done so far to define the calorimeter design, the satisfying results obtained with the test beam of the prototypes as well as the current production phase will be reported in this presentation. At the moment, all the components for the first disk have been tested and characterized. According to the Mu2e Collaboration plans, calorimeter construction will begin in spring 2020.

Speaker: Luca Morescalchi (INFN - Pisa)

ichep2020_morescalchi.pdf

110 Construction and performance of 4-D CsI calorimeter for the $K_L¥to ¥pi^0¥nu¥bar{¥nu}$ search of KOTO experiment

One of the key issues of the search for the $K_L\to \pi^0\nu\bar{\nu}$ decay mode is to suppress the backgrounds to the signature with only two photons from the $\pi^0$ in the final state. We use an electromagnetic calorimeter and hermetic veto counters in the KOTO experiment at J-PARC. The calorimeter is made of 50 cm-long undoped CsI crystals stacked in a 1.9 m-diameter cylinder. Each crystal is read out with a PMT on the back surface of the crystals. A major background is caused by neutrons generating two showers in the calorimeter. Neutrons tend to have interactions deeper than photons. In the autumn of 2018 we upgraded the calorimeter by installing 4000 silicon photomultipliers (SiPMs) on the front surface of the crystals. The depth information is available by measuring the timing difference between SiPMs and PMTs. The construction and performance of this new calorimeter by using data of 2019 will be presented. Less than 0.5 neutron background events are expected when we reach the sensitivity of one $K_L\to \pi^0\nu\bar{\nu}$ event. The signature has a branching fraction of $(3.0\pm0.3)\times10^{-11}$ in the standard model.

Speaker: Katsushige Kotera (DESY/Shinshu University (JP))

0k728_ICHEP_coterra_v6.pdf

111 Analysis of the magnetic field in the Fermilab muon g-2 experiment

The muon g-2 experiment at Fermilab seeks to confirm or deny the ~3.5 $\sigma$ discrepancy between the Standard Model prediction of the muon anomalous magnetic moment, $a_{\mu}$, and its experimental value. The experiment measures $a_\mu$ directly from the ratio of the muon precession frequency in a uniform storage ring magnetic field to the Larmor frequency of free protons in the same field. Every few days, an NMR ‘trolley’ maps out the storage ring field. Field drifts between trolley runs are tracked by ‘fixed’ NMR probes embedded in the vacuum chamber walls. These measurements are interpolated to determine the field in the storage region, which is convolved with the muon beam distribution to determine the effective magnetic field, $\langle$B$\rangle$. A precise determination of $\langle$B$\rangle$ is crucial; half of the error budget is attributed to the magnetic field uncertainty. The magnetic field analysis techniques and a summary of the results will be presented.

Speaker: Saskia Charity (Fermi National Accelerator Laboratory)

ICHEP_SaskiaCharity_Jul2020.pdf

112 Muon g-2 beam and spin systematic effects for Run-1

The muon g-2 Experiment at Fermilab measures the anomalous magnetic moment, $a_\mu$, with improved precision compared to the previous experiment at Brookhaven National Lab.
The greater than 3 standard deviations difference between Standard Model prediction and the previous BNL, $a_\mu$, measurement hints at the possibility of new physics. Positive polarized muons are circulated in the storage ring and the experiment precisely determines the muon anomalous precision frequency, $\omega_a$, (spin precession relative to momentum). The $\omega_a$ is determined from calorimeter measurements of decay positron time and energy. The experiment also needs to precisely determine the average magnetic field seen by the muons, which is based on continuous NMR probe measurements. A detailed understanding of beam and spin systematic effects is required for the precise determination of $\omega_a$. This talk gives a review of the beam and spin systematic effects that are significant for determination of $\omega_a$ in the 2018 Run-1 analysis.

Speaker: Dr Sudeshna Ganguly (University of Illinois at Urbana-Champaign)

ICHEP_beamdynamics_Sudeshna.key

ICHEP_beamdynamics_Sudeshna.pdf

113 ALPIDE pixel detector for tracking in space.

The ALPIDE MAPS chip used in the ALICE silicon tracker upgrade, represents the state of the art for pixel-based tracking with silicon.
We investigated the possibility to use the ALPIDE chip in space applications using a setup derived from the ALICE Outer Barrel HIC.
We first addressed the issue of the power consumption and we will report on a special setup that provides a relevant power saving.
We then passed to address heat dissipation, material qualification for space, performance in vacuum and resistance to launch vibrations.
From our qualification test the ALPIDE chip results as a viable solution for space applications.

Speaker: Paolo Zuccon (Universita degli Studi di Trento and TIFPA Trento)

zuccon_ICHEP2020.pdf

5:15 PM Coffee break

114 The MicroBooNE Experiment

MicroBooNE is a 100-ton scale liquid-argon time projection chamber (LArTPC) neutrino experiment located on the Booster neutrino beamline at Fermilab. The experiment first started collecting neutrino data in October 2015. The detector, the first in the short-baseline neutrino program at Fermilab, is the longest operating LArTPC to date and plays an important role in a phased program towards the construction of massive kiloton scale detectors for future long-baseline neutrino physics (DUNE). We present results on the operation and performance of the detector after four years of data taking, highlighting accomplishments towards reconstruction, calibration and detector physics.

Speaker: Ralitsa Sharankova (Tufts University)

ICHEP2020_sharankova.pdf

115 Construction, installation and operation of ProtoDUNE-SP

The single-phase liquid argon TPC at CERN (ProtoDUNE-SP) is an engineering prototype for the first module of the DUNE far detector. This prototype which has dimensions of a cube of about 10m edge, provide full validation of the use of the membrane tank technology for large dimension cryostats. Furthermore, the very high performance of the protoDUNE-SP TPC with more than 500 days of continuous and stable operation, demonstrated the reliability of the LAr detection technology at a scale never tested before. In this talk we will review the main characteristics and milestones of the construction and installation of protoDUNE-SP which provide a series of benchmarks for DUNE. The performance for several different detector working points will also be discussed.

Speaker: Stefania Bordoni (Michigan State University (US))

protodunesp_sbordoni_ICHEP.pdf

116 Performance of photon detectors in ProtoDUNE-SP

The single-phase liquid argon prototype at CERN (ProtoDUNE-SP) is designed to act as a testbed and prototype for the elements of the first far detector module of DUNE. ProtoDUNE-SP collected data in the H4-VLE beamline at CERN in the autumn of 2018 and accumulated 4M particles (electrons, muons, pion, kaons and protons) ranging from 0.3 to 7 GeV/c and a large number of cosmic ray events since then. ProtoDUNE-SP employs three different photon detector technologies. This talk will present the performance of the photon detectors in ProtoDUNE-SP, including detector calibration, efficiency measurements, attenuation studies, timing resolution, calorimetric energy reconstruction from scintillation light and energy resolution of electrons.

Speaker: Dante Totani (Fermi National Accelerator Lab. (US))

DanteTotaniICHEP2020.pdf

117 Measurement of space charge effects in ProtoDUNE-SP

The accumulation of positive ions in a LArTPC located on the surface can distort the electric field and the reconstructed particle trajectories. It is critical to understand and correct for the space charge effects in order to achieve the desired spatial and calorimetric resolutions in the LArTPC. This talks will present the measurement of space charge effects using cosmic ray muons in ProtoDUNE-SP.

Speaker: Michael Mooney (Colorado State University)

DUNE_ICHEP2020_20_07_28.pdf

118 Energy calibration of the ProtoDUNE-SP TPC

The single-phase liquid argon prototype at CERN (ProtoDUNE-SP) acts as a validation of the design for the DUNE single-phase far detector. With a total mass of 770 tons, it is the largest monolithic liquid argon single-phase time projection chamber in the world. ProtoDUNE-SP collected test-beam in autumn of 2018 and has been collecting cosmic and special calibration data since the end of 2018. With more than 500 days of continuous operation, the long-term performance, stability and calorimetric measurements of the detector will be discussed in this talk.

Speaker: Richard Diurba (University of Minnesota)

protoDUNE_dQdxCalib_Final.pdf

protoDUNE_dQdxCalib_Final_typofixed.pdf

119 The MCP based Large Area PMTs for Neutrino Detector

The large scalar neutrino detectors (JUNO, HyperK), need the 20 inch area PMTs as the photo-detection device for their large photocathode coverage and less electronic channels. In 2009, the researchers at IHEP have conceived a new concept of large area PMTs, of which the small MCP units replace the bulky Dynode chain. After several years R&D, the 20 inch MCP-PMT was successfully produced. This type of PMT has large sensitive area, high QE, and large P/V for good single photon detection. The JUNO ordered 15000 pic 20 inch MCP-PMTs in Dec.2015. Then, from 2017 to 2020, all the 20-inch PMTs will be produced and tested one by one in the company for JUNO. This presentation will talk about the R&D, the mass production and batch test result of the 13K pieces of MCP-PMT prototypes for JUNO. Further more, another Flower-liked MCP-PMT was designed with the TTS less than 5ns, and this new type of 20 inch MCP-PMT has already evaluated by the PMT group in HyperK, and also be used in the LHAASO project in China.

Speaker: Sen Qian (Institute of High Energy Physics,CAS)

@--ICHEP-LPMT--V5.0.pdf

120 Performance of the SoLid reactor neutrino detector

The SoLid collaboration operates since 2018 a 1.6 ton neutrino detector near the Belgian BR2 reactor, with as a main goal the search for observation of the oscillation of electron anti-neutrinos to previously undetected flavor states.
The highly segmented SoLid detector employs a novel compound scintillation technology based on PVT scintillator in combination with a LiFZnS screens containing 6Li isotopes. The experiment has demonstrated a channel-to-channel response that can be controlled to the level of a few percent, an energy resolution of better than 14% at 1 MeV, and a determination of the interaction vertex with a precision of 5cm.

In this contribution we will discuss the technology choices that were made to construct the SoLid experiment, the experience gained from its commissioning, calibration, and the detector performance characteristics during two years of non-stop operation. We will also discuss an ongoing upgrade program of the detector and the expected improvements in performance associated with that.

Speaker: Noe Roy (Laboratoire de Physique des 2 infinis Irène Joliot-Curie)

ichep_solid_detector.pdf

7:00 PM Coffee break

121 The sPHENIX experiment at RHIC

The sPHENIX experiment is the successor the PHENIX experiment at RHIC and is optimized to study heavy flavor and jets arising from heavy ion collisions. The detector utilizes advanced technologies such as a monolithic active pixel vertex detector while also repurposing technologies originally from other high energy experiments such as BaBar, ATLAS and ALICE. In this talk we will show the design and status of the sPHENIX detector whilst also presenting the projected physics capabilities and planned measurements that the collaboration will work to achieve. sPHENIX is expected to begin data taking in 2023.

Speaker: Cameron Dean (Los Alamos National Laboratory (US))

sPHENIX_ICHEP20200728_C_Dean.pdf

122 ALICE upgrades for Run 3

The ALICE detector at the LHC is undergoing major upgrades during the Long Shutdown 2 (2019/20). A new Inner Tracking System (ITS) is being installed and the Time Projection Chamber (TPC) has been equipped with new GEM-based read-out chambers. Together with the new front-end-electronics they will enable us to read out the TPC continuously and record the full minimum-bias interaction rate of 50 kHz in Pb-Pb. The new Monolithic Active Pixel Sensors used for the ITS will significantly improve the impact parameter resolution and tracking efficiency, especially for particles with low transverse momentum, as well as the readout rate capability. In addition, a pixel tracker will be installed in front of the muon spectrometer, and the readout electronics of several other detectors are being replaced with faster technology. These upgrades also require a completely new online computing system that has the dual task of data acquisition and performing the first pass of the reconstruction to compress data and remove noise hits from the data stream. This talk will summarize the motivation and realization of the upgrades and report on the status of the installation and commissioning.

Speaker: Stefano Matthias Panebianco (Université Paris-Saclay (FR))

Panebianco_ICHEP2020.pdf

123 Status of the Fast Interaction Trigger for ALICE Upgrade

As part of the preparations for the LHC Run 3 and 4, the ALICE experiment at CERN is making a thorough upgrade of the setup. In particular, all ALICE subsystems have to cope with the increased interaction rate of 50 kHz in Pb-Pb and up to 1 MHz in pp collisions. Comparing with Run 2, this is up to two orders of magnitude more collisions. The solution for the majority of ALICE detectors is to switch to a continuous readout, but several of the older systems (TRD, CPV, HMPID, EMCAL, DCAL and PHOS) would still need an external trigger or a wakeup signal.

The Fast Interaction Trigger (FIT) will generate a minimum-bias and a multiplicity trigger with the maximum latency below 425 ns. It will also measure collision time with a resolution of < 40 ps and serve as the main ALICE luminometer, providing direct, real-time feedback to the LHC for the beam tuning. In the offline analysis FIT will aid in the reconstruction of the vertex position, assess forward particle multiplicity, centrality and event plane, and will be used for the study of diffractive physics at forward rapidity.

FIT consists of three sub-systems: a fast Cherenkov detector array using MCP-PMTs as photosensors, a large scintillator ring employing a novel light collection system, and a scintillator-based Forward Diffractive Detector. After a short description of the detector components, functionalities and a brief summary of the physics objectives, the key test results of the assembled detector will be presented and discussed.

Speaker: Maciej Slupecki (Helsinki Institute of Physics (FI))

2020.07.28-Slupecki-ALICE-FIT_v8.pdf

124 Performance of the LHCb detector in the Run 2

The LHCb experiment is a flavour physics detector, designed to study decays of b and c hadrons for measurements of CP violation and rare decays. Its performance is based on precision tracking and particle-identification systems. In order to accomplish its wide program of physics measurements, the LHCb collaboration has developed in the past years a set of algorithms for reconstruction of the trajectories of charged particles, as well as identification of charged and neutral particles. Several data-driven approaches have been developed to provide a precise calibration of the tracking and particle-identification efficiencies, which are crucial ingredients of many physics analysis. A number of novel strategies have been developed during Run 2 of the LHC to improve the precision of this calibration. This talk presents an overview of the LHCb performance in Run 2 of the LHC, with emphasis on recent improvements.

Speaker: Martina Pili (University of Oxford (GB))

ICHEP2020_Pili_v1.pdf

125 The LHCb Upgrade Programme for Run 3 and Run 4

The LHCb experiment at the LHC is designed to capture decays of b- and c-hadrons for the study of CP violation and rare decays. It has already had a transformative impact in the field of flavour physics as well as making many general purpose physics measurements in the forward region. At the end of Run-II, many of the LHCb measurements will remain statistically dominated. For this reason the experiment is being upgraded in a first step - Upgrade I - to run at higher luminosity of 2$\times 10^{33}$cm$^{-2}$s$^{-1}$ after 2020. The trigger scheme, which currently has a 1 MHz lowest level hardware rate, will be transformed to a strategy whereby the entire experiment is read out at 40 MHz to a flexible software trigger. The increased luminosity and trigger efficiency anticipated at the upgrade will allow a huge increase in precision, in many cases to the theoretical limit, and the ability to perform studies beyond the reach of the current detector. In addition the flexible trigger and unique acceptance opens up opportunities in topics apart from flavour, reinforcing the role of LHCb as a general purpose detector in the forward region In order to allow the triggerless readout the front end electronics of all subdetectors will be changed, and many subdetectors will be upgraded to cope with the increased occupancy and radiation levels. During the long shutdown between Run 3 and Run 4 the most irradiated parts of the detector will be replaced and other detector consolidation and improvement steps will be carried out.

Speaker: Federico Alessio (CERN)

200725_ICHEP_LHCbUpgrades_v3.pdf

126 The LHCb VELO Upgrade

The LHCb experiment is a detector at the LHC designed to capture decays of b- and c-hadrons for the study of CP violation and rare decays. At the end of Run-II, many of the LHCb measurements remain statistically dominated. For this reason the experiment is currently being transformed, in the Upgrade I programme, to run at higher luminosity from Run III onwards. The trigger scheme will be transformed to read out at 40 MHz to a flexible software trigger. In order to allow the new readout scheme the front end electronics will be changed, and the detectors need cope with the increased occupancy and radiation levels anticipated at the upgrade. The Vertex Locator (VELO) surrounding the interaction region, whose role is to reconstruct and trigger on the primary and secondary vertices of the events.

The upgraded VELO is composed of 52 hybrid silcon pixel modules placed along the beam axis, divided into 2 retractable halves. Each module is equipped with 4 silicon pixel tiles, each read out by 3 VeloPix ASICs. The pixels have a square pitch of 55 microns and the sensors are produced in 0.2 mm thick p-in-n type silicon. The sensors must withstand an integrated fluence of um^2, a roughly equivalent dose of 400 MRad The highest occupancy ASICs will have pixel hit rates of 800 Mhit/sf, with a total rate of 1.6 Tbit/s for the whole detector. The VELO upgrade tiles are mounted onto a cooling substrate made of thin silicon plates with embedded micro-channels that allow the flow of liquid CO$_2$. The secondary vacuum in which the modules are located is separated from the beam vacuum by a thin custom made foil. This foil is be manufactured through a novel milling process and possibly thinned further by chemical etching. The upgraded VELO is currently under construction. The detector R\&D, module thermal performance, and the VELO Upgrade production status will be presented.

Speaker: Peter Svihra (University of Manchester (GB))

The LHCb VELO Upgrade I

127 The pixel vertex detector at Belle II

The vertex detector at Belle II has four outer layers of silicon strip detectors (SVD) and two inner pixel layers (PXD) at a distance of 14 and 22 mm to the interaction point. The PXD is based on DEPFET technology, which combines signal generation and first amplification in a single device and allows for the construction of a very light-weight device. The material budget of a single layer inside the acceptance region is only about 0.2% of a radiation length including all structures needed for support and thermal management. This is only possible with the unique approach of the “all-silicon module” where all read-out ASICs and interconnects are integrated in a micro-machined piece of silicon with the active DEPFET pixel sensor as its integral part.
The Belle II PXD Collaboration designed and fabricated the sensor, the read-out and steering ASICs, the low-mass module and ladder concept, services and power supplies, cooling, DAQ system and slow control. It is the first time that the DEPFET technology is deployed in a HEP experiment.
The PXD is in operation as part of the Belle II experiment at KEK since March 2019 and is taking data with very good performance meeting the expectations. Since start of operation, the accelerator SuperKEKB reached a peak luminosity beyond 1e34 /cm2s and about 10 fb-1 have been recorded at the time writing. The final goal for the peak luminosity of the machine is 8e35 /cm2s and the pixel detector is designed to be operated at this final luminosity up to the accumulated data set of 50 ab-1.
The lessons learned during construction, commissioning, and operation of the first DEPFET based vertex detector will be presented.

Speaker: Felix Mueller (DESY Hamburg)

ICHEP_2020_Felix_Mueller.pdf

Quark and Lepton Flavour Physics: Session I - Premiere

Conveners: Ruth Van de Water (Fermilab), Karim Massri (CERN), Carla Gobel Burlamaqui De Mello (Pontificia Universidade Catolica (BR))

Replay

128 Purely Leptonic Rare decays at LHCb

During Run 1 and 2 of the LHC, the LHCb experiment has collected large samples of beauty-hadron decays corresponding to an integrated luminosity of 9/fb at pp centre-of-mass energy of 7, 8 and 13 TeV. Very rare decays are discussed, with an emphasis on Flavour-Changing Neutral-Current processes of the type $B^0_{(s)} \to l^+ l^-$. Anomalies in the branching fractions of these decays are also discussed and connected with tests of Lepton-Flavour-Universality.

Speaker: Lauren Emma Yeomans (University of Liverpool (GB))

ICHEP_Purely _Leptonic_Rare_Decays_at_LHCb.pdf

129 Search for New Physics with rare decays at CMS

Recent CMS results are reported either for the observation of the B0s to mu+mu- decay and for the search of the B0 to mu+mu- decay by adding the 2016 13TeV data to the Run-I data and for the search of the tau to 3 muons decay, with 2016 13 TeV data, by considering tau leptons coming both from Ds and W decays.

Speaker: Ozlem Ozcelik Ozludil (Bogaziçi Univ., Dept of Physics)

ICHEP2020-OzlemOzcelik.pdf

130 ATLAS results on Heavy Flavour production and decay (including rare processes)

The heavy flavour production and decays are studied with the ATLAS detector, mainly through final states containing muons. This talk will summarise recent results from ATLAS, including measurements on Bc mesons decaying in different final states and of Ds cross-sections. The latest results on the studies of rare processes are also presented. Particular attention will be given to Flavour Changing Neutral Current processes, such as the decay of Bs and B0 into two muons.

Speaker: Sally Seidel (University of New Mexico / ATLAS)

ichep2020-talk-v4.pdf

131 Study of $B$ and $B_{s}$ Decays at Belle

We present the study of $B_{s}$ decays using 121.4 fb$^{-1}$ of data collected at $\Upsilon(5S)$ resonance with the Belle detector at the KEKB asymmetric-energy electron-positron collider. We search for $B_{s}\to \eta^{\prime} \eta$ and $B_{s}\to \eta^{\prime} K^{0}_{S}$, which are suppressed in the standard model (SM) and can receive contribution of physics beyond the SM. We also report the first model-independent measurement of B($B_{s}\to D_{s} X$) using $B_{s}$ semileptonic tagging; this is necessary for measuring absolute rates and branching fractions of other $B_{s}$ decays. In addition, we present precise measurements of the branching fraction and CP asymmetry in $B\to \phi \phi K$ decays using Belle data that corresponds to 772 million $B\overline{B}$ pairs. These decays are mediated by the $b\to s$ FCNC transition, where one can observe large CP violation due to interference of potential new-physics amplitudes appearing in the loop with the $b\to c$ tree-level transition of $B\to \eta_{c} K$, $\eta_{c}\to \phi \phi$.

Speaker: Nisar Nellikunnummel (BNL)

nisar_ICHEP.pdf

132 Rare B-decay anomalies

Rare $B$-decays are among the most promising indirect probes for the search for New Physics. In recent years there have been several significant hints for physics beyond the SM in semileptonic $b\to s \ell \ell$ transitions. Interestingly, the analysis of these so-called B anomalies indicate a consistent pattern of lepton flavour non-universality.
We present updated global fits of Wilson coefficients both when only one or two Wilson coefficients are involved as well as in a 20-dimensional fit. Using the new data of the LHCb angular analysis of the $B\to K^* \mu^+ \mu−$ decay we make statistical comparisons to determine whether the most favoured explanation of the anomalies is New Physics or underestimated hadronic effects.

Speaker: Siavash Neshatpour

Siavash_ICHEP2020.pdf

133 Rare charm decays at LHCb

LHCb is playing a crucial role in the study of rare and forbidden decays of charm hadrons, which might reveal effects beyond the Standard Model. We present the latest searches for, and measurements using, rare charm decay processes with two leptons in the final state.

Speaker: Chris Burr (CERN)

2020-07-28_ICHEP-2020-Rare-charm-decays-in-LHCb.pdf

134 Radiative and Rare Charm Decays at BESIII

In this talk, we present the latest result on radiative and rare/forbidden decays for D mesons at the BESIII experiment based on 2.92 fb-1 and 3.19 fb-1 data taken at the center-of-mass energy 3.773 4.178 GeV with the BESIII detector, respectively. Based the data at 4.178 GeV, a search for the rare radiative leptonic decay Ds->gamma e+ nu is performed for the first time with negative result and an upper limit (UL) of the branching fraction(BF) is set to be less than 1.310E-4 at 90\% confidence level (CL). With this data sample, we also search for the rare decay Ds-> p bar e+ nu. No significant signal is observed, and an UL B(Ds -> p pbar e+ nu)<2.010E-4 is determined at the 90\% CL. Using the dataset at 3.773 GeV, we search for rare decays of D-> h(h’)e+e- with double tag method, where h(‘) are hadrons. No significant excess over the expected backgrounds is observed, the ULs on the signal BFs at the 90\% CL are determined. For the D+ decays, the searches are performed for the first time, while for D0 decays, the ULs are improved in general by a factor of 10, compared to previous measurements. All the ULs on the BF, at the level of $10E-5~10E-6, are above the SM predictions, which include both LD and SD contributions. Also, we search for the Majorana neutrino in the lepton number violating (LNV) decays $D\to K pi e+e-. No significant signal is observed, and the ULs on the BF at the 90\% CL are set to be less than few $10E-6. The Majorana neutrino is searched for with different mass assumptions ranging from 0.25 to 1.0 GeV/ in the decays D0 -> K- e+ nu_N(pi- e+) and D+->KS e+ nu_N(pi-e+), and the UL on the BF at the 90\% CL are extracted to be at the level of $10E-7~10E-6. The constraints on the mixing matrix element |V_{eN}|^2 are also evaluated.

Speaker: Dr Bo Zheng (University of South China)

Radiative and Rare Charm Decays at BESIII-BoZheng(1).pdf

135 Rare and forbidden decays of D0 meson

We report the observation of the rare charm decay $D^0\to K^-\pi^+e^+e^-$, a search for nine lepton-number-violating and three lepton-flavor-violating neutral charm decays of the type $D^0\to h^- h^{'-} \ell^+ \ell^{'+}$, and $D^0\to h^- h^{'+} \ell^+ \ell^{'-}$, and a search for seven lepton-number-violating decays of the type $D^{0}\rightarrow X^{0} e^{\pm} \mu^{\mp}$, where $h$ and $h^{\prime}$ represent a $K$ or $\pi$ meson, $\ell$ and $\ell^{\prime}$ an electron or muon, and $X^{0}$ a $\pi^0$, $K^0_S$, $K^{*0}$, $\rho^{0}$, $\phi$, $\omega$, or $\eta$ meson. The results are based on $468$ fb$^{-1}$ of $e^+e^-$ collision data collected at or close to the $\Upsilon(4S)$ resonance with the $BABAR$ detector at the SLAC National Accelerator Laboratory.

Speaker: Racha Cheaib (University of British Columbia)

ICHEP_BABAR_RareDDecays.pdf

5:30 PM Coffee break

virtual coffee served

136 Recent gems from kaon and their repercussions for future directions

Kaons have played a crucial role in Particle Physics from their early history including some profound discoveries. In this talk I will give account of recent progress on several challenging issues that have been with us for a long time. Seen in the light of this progress what can we learn from many of the flavor anomalies of the past many years will also be discussed.

Speaker: Amarjit Soni (Amarjit)

kaons final 4 ICHEP20.pdf

137 Search for New Physics via the $K_L \to \pi^0 \nu \bar{\nu}$ decay at the J-PARC KOTO experiment

The purpose of the KOTO experiment, being conducted at J-PARC (Ibaraki Japan), is to search for New Physics
via the rare decay $K_L\rightarrow \pi^0 \nu \bar{\nu}$ using the high intensity $K_L$ beam provided by
the 30~GeV proton synchrotron.
The $K_L\rightarrow \pi^0 \nu \bar{\nu}$ decay is suppressed in the standard model, and
its observation may reveal hints of new physics.
The signature of $K_L\rightarrow \pi^0 \nu \bar{\nu}$ is two $\gamma$'s from a $\pi^0$ and
no other particles in the detectors surrounding the decay region.

For the data collected between 2016 and 2018, a blind analysis technique was adopted to avoid
human bias in the determination of the selection criteria.
We unblineded the signal region in the summer of 2019, and observed candidate events.
Since then, we have been checking our software and hardware, and possibilities of backgrounds that we might have missed.
In this presentation, we report the progress in the analysis and the obtained feedback from the data taken in 2019 and 2020.

Speaker: Dr Nobuhiro Shimizu (Osaka University)

ICHEP_2020_shimizu_koto_v3.pdf

138 New result on the search for the $K^+ \to \pi^+ \nu\bar\nu$ decay at the NA62 experiment at CERN

The ultra-rare K+ —> pi+nunu decay benefits from a precisely predicted branching ratio in the SM (8.4 +- 1.0) x 10^{-11}, being almost free from theoretical uncertainties, and most importantly from a very high sensitivity to a variety of beyond-the-standard-model scenarios, making it one of the best candidates to reveal indirect effects of new physics in the flavour sector.
The NA62 experiment at the CERN SPS, designed to measure the branching ratio of K+ —> pi+ nunu with a decay-in-flight technique, collected data in 2016-2018. New results from the analysis of 2018 data, the largest data set so far collected, will be presented. The result will represent the most accurate measurement so far achieved of this ultra-rare decay.
Future prospects and plans for data taking from 2021 will also be presented.

Speaker: Radoslav Marchevski

RadoslavMarchevski_ICHEP_2020.pdf

139 New measurement of the $K^+\to\pi^+\mu^+\mu^-$ decay at NA62

The flavour-changing neutral current decay $K^+\to\pi^+\mu^+\mu^-$ is induced at the one-loop level in the Standard Model, and is well suited to explore its structure and, possibly, its extensions. The NA62 experiment took data in 2016--2018 with the main goal of measuring the $K^+\to\pi^+\nu\bar\nu$ decay. A scaled down di-muon trigger chain was operating along with the main trigger during the whole data taking period resulting in a large sample of about $3 \times 10^{12}$ kaon decays in the fiducial volume recorded using the di-muon trigger. New results from an analysis of the $K^+\to\pi^+\mu^+\mu^-$ decay using this sample will be presented.

Speaker: Lubos Bician (CERN)

ICHEP_2020_bician_kpmm.pdf

140 Latest results on rare kaon decays from the NA48/2 experiment at CERN

The NA48/2 experiment at CERN reports the first observation of the K± → π± π0 e+ e− decay from an exposure of 1.7×10^11 charged kaon decays recorded in 2003−2004. A sample of 4919 candidates with 4.9% background contamination allows the determination of the branching ratio in the full kinematic region. The study of the kinematic space shows evidence for a structure dependent contribution in agreement with predictions based on chiral perturbation theory. Several P- and CP-violating asymmetries are also evaluated.
The most precise measurement of the charged kaon semi-leptonic form factors obtained by NA48/2 with 4.4 million Ke3 and 2.3 million Kmu3 events collected in 2004 will also be presented.

Speaker: Mauro Raggi (LNF INFN)

raggi_ICHEP.pdf

raggi_ICHEP.pptx

141 Latest D0 results on exotic hadrons produced in $p\bar p $ collision

We selected candidate events for production of the exotic charged charmonium-like states $Z_c^{\pm}(3900)$ decaying to $ J/\psi\pi^{\pm}$ and $X(3872)$ decaying to $J/\psi\pi^{\pm}\pi^{\mp}$. We use 10.4 $\rm fb^{−1}$ of $p\bar p$ collisions recorded by the D0 experiment at the Tevatron collider at $\sqrt s=$1.96 TeV. We measure the $Z_c$ mass and natural width using subsample of candidates originating from semi-inclusive weak decays of b-flavored hadrons and search for the $Z_c$ prompt production. We measure different production properties of the $X(3872)$, such as the prompt fraction as a function of the transverse momentum, that are compared to $\psi(2S)\to \psi\pi^{\pm}\pi^{\mp}$ production. The sample of 10.4 $\rm fb^{−1}$ is also used to search for the inclusive production of the pentaquark states observed in $pp$ collisions at LHCb, $P_c(4400)$ and $P_c(4457)$, decaying to $J/\psi p$.

Speaker: Alexey Drutskoy

Drutskoy_ICHEP_2020_07_28.pdf

142 Search for QCD exotic states at CMS