The 41st International Symposium on Physics in Collision

Tbilisi State University

Tbilisi State University

1 Chavchavadze Av., Tbilisi, Vake district

The International Symposium on Physics in Collision is a conference series that began in 1981 in Blacksburg, Virginia, USA. The program of the symposium is composed of invited talks and contributions in poster sessions. Invited speakers will review and upadate key topics in particle physics and related topics in which new results have been published in the last year or are reasonably expected to be so before the next symposium. The aim of presentations is to encourage informal disucssions of new experimental results and their implications. The topics at the symposia cover a wide range of physics subjects from accelerator-based particle physics to astroparticle physics.

Please visit PIC2022 official web page

  • Achim Stahl
  • Alberto Garfagnini
  • Alexander Machavariani
  • Alexandre Gurchumelia
  • Anastasiia Kurova
  • Andro Kacharava
  • Archil Durglishvili
  • Caterina Braggio
  • Christophe Pol A Roland
  • Cong Li
  • Da Xu
  • Dmitry Naumov
  • Edisher Tskhadadze
  • Fabio Cardillo
  • Francesco Giuli
  • Gela Devidze
  • Giorgi Kistauri
  • Giorgi Macharashvili
  • Gogita Papalashvili
  • Hailong Ma
  • Ioana Maris
  • Iuliia Zalevskaia
  • Javier Brochero
  • Jingqing Zhang
  • Juansher Jejelava
  • Julia Tjus
  • Keti Kaadze
  • Lali Kharkhelauri
  • Liana Abesalashvili
  • Livia Ludhova
  • Lluis Marti-Magro
  • Luca Pelicci
  • Luca Pelicci
  • Lukas Novotny
  • Maria Marcisovska
  • Mariam Abuladze
  • Mariam Rifai
  • Markus Bachlechner
  • Medina Ablikim
  • Merab Eliashvil
  • Michal Marcisovsky
  • Mikheil Nioradze
  • Mingshui Chen
  • MIrian Tabidze
  • Nika Basharuli
  • Nodar Lomidze
  • Ornella Juliana Piccinni
  • Pavel Pakhlov
  • Philipp Soldin
  • Prasanth Krishnan Kodassery
  • Rajeev Singh
  • Ramaz Kvatadze
  • Revaz Shanidze
  • Richard Teuscher
  • Ronaldo Colque
  • Sebastian Trojanowski
  • Sergey Barsuk
  • Sonia Kabana
  • Swathi Karanth
  • Tagir Aushev
  • Tamar Babutsidze
  • Tamar Djobava
  • Tamar Mamadashvili
  • Tamar Zakareishvili
  • Taritree Wongjirad
  • Thomas Mueller
  • Vato Kartvelishvili
  • Wolfgang Lohmann
  • Xiao-Rui Lyu
  • Xiaoyan Shen
  • Yury Kudenko
  • zhou hui
  • Zurabi Gachechiladze
    • Registration
    • City Excursion
    • Session 5
    • 10:20 AM
      Coffee break
    • Session 6
    • 12:40 PM
    • Session 7
    • 3:40 PM
      Coffee break
    • Lightning talk session
      • 18
        High Precision Muon Reconstruction Performance with ATLAS at LHC

        Muon reconstruction performance plays a crucial role in the precision and sensitivity of the Large Hadron Collider (LHC) data analysis of the ATLAS experiment. The 139 fb-1 of proton-proton collision data collected during the LHC Run-2 poses both a challenge and opportunity for the detector performance. Using di-muon resonances we are able to calibrate to sub per-mil accuracy the detector response for electrons and muons.This talk will present recently released results significantly improving the measurement of muon reconstruction, identification and calibration performance with innovative techniques. New analysis techniques are exploited which involve multivariate analyses for rejecting background hadrons from prompt leptons from the hard interactions as well as innovative in-situ corrections on data that reduce biases in muon momenta induced from residual detector displacements. These techniques are fundamental for improving the reach of measurements and searches involving leptons, such as Higgs decays to dileptons and ZZ or high precision measurements of fundamental constants of the SM such as the Higgs and W masses or the Weinberg's weak mixing angle.

        Speaker: Siyuan Yan
      • 19
        Tests of Standard Model with beauty meson rare decay processes and CP-violation measurements at ATLAS

        The ATLAS experiment has performed measurements of B-meson rare decays proceeding via suppressed electroweak flavour changing neutral currents, and of mixing and CP violation in the neutral B0s meson system. This poster will focus on the latest results from the ATLAS collaboration, such as rare processes B0s→μμ and B0d→μμ, and CP violation in B0s→J/ψ ϕ decays, where the CP-violation phase ϕs can be measured together with the B0s lifetime properties.

        Speaker: Lukas Novotny
      • 20
        Response of the ATLAS Tile Calorimeter at Test Beams using Phase II upgrade readout

        The Large Hadron Collider (LHC) Phase II upgrade aims to increase the accelerator luminosity by a factor of 5-10. Due to the expected higher radiation levels and the aging of the current electronics, a new readout system of the ATLAS experiment hadronic calorimeter (TileCal) is needed. A prototype of the upgrade TileCal electronics has been tested using the beam from the Super Proton Synchrotron (SPS) accelerator at CERN.

        Data were collected with beams of muons, electrons and hadrons at various incident energies and impact angles. The muons data allow to study the dependence of the response on the incident point and angle in the cell. The electron data are used to determine the linearity of the electron energy measurement. The hadron data will allow to tune the calorimeter response to pions and kaons modelling to improve the reconstruction of the jet energies. The results of the ongoing data analysis will be presented in the poster.

        Speaker: Tamar Zakareishvili (Ivane Javakhishvili Tbilisi State University (GE))
      • 21
        Response of the ATLAS Tile Calorimeter to single isolated charged hadrons

        The response of the ATLAS hadronic Tile Calorimeter to single isolated
        charged hadrons is probed analysing of LHC proton-proton collisions data
        at √s = 13 TeV collected in 2017 and corresponding to an integrated
        luminosity of 144.9 pb-1. The calorimeter response is determined as the
        ratio of the energy deposited in the calorimeter (E) divided by the
        momentum measured in the ATLAS Inner Detector (p). The average of E/p
        measured in data is 0.5896 ± 0.0001 (stat), compared to an expected
        value of 0.593 ± 0.001 (stat) obtained using Pythia8 simulated multijet
        events. A good agreement between experimental and simulated results is
        observed confirming the goodness of the calorimeter energy calibration
        at the EM scale.

        Speaker: Archil Durglishvili (Ivane Javakhishvili Tbilisi State University (GE))
      • 22
        Physics Prospects of the JUNO Experiment

        The Jiangmen Underground Neutrino Observatory (JUNO) is a 20 kton liquid scintillator detector with the main goal to determine the neutrino mass ordering (NMO). JUNO construction in southern China,in an underground laboratory with 650 m rock overburden, is expected to be completed by the end of 2023.
        Thanks to high scintillation light yield, high transparency, 78% optical coverage and large photon detection efficiency, JUNO will achieve an unprecedented energy resolution of 3% at 1MeV. This challenging design is required in order to achieve a $3 \sigma$ sensitivity to neutrino mass ordering within 6 years measurements of reactor antineutrinos, with 53 km baseline. JUNO is the only experiment that will tackle the NMO using the neutrino oscillation in vacuum, complementary to other experiments exploiting the matter effects on oscillation of atmospheric and accelerator neutrinos.
        The precision measurements of the oscillation pattern, JUNO will determine the neutrino oscillation parameters $\Delta m^{2}_{12}$, $\theta_{12}$, $\Delta m^{2}_{13}$ with sub-percent precision. Furthermore, JUNO has a vast potential for other fields in (astro-)particle physics, with energies ranging from sub-MeV to several GeV, covering solar, geo, supernova, and atmospheric neutrinos, as well as the potential to search for rare processes and physics beyond the standard model. This poster gives an overview of the JUNO experiment with a focus on its physics potential on the various topics described above.

        Speaker: Mariam Rifai
      • 23
        Ultrahigh Vacuum Developments for the Einstein Telescope

        The Einstein Telescope, the European Gravitational Detector of the next generation, will need the largest ultrahigh vacuum system ever build. I will present some of the development towards this system.

        Speaker: Prof. Achim Stahl (Rheinisch Westfaelische Tech. Hoch. (DE))
      • 24
        Broad Band Waveguide to Coaxial Transition for HOM Suppression in RF Cavities for Future Synchrotron Light Sources

        In the modern storage ring light sources, exploiting multi-bunch beams, the longitudinal and transverse coupled bunch instabilities are predominantly driven by higher order modes (HOM) of the accelerator RF cavities. In order to suppress the HOM to a harmless level, we propose using a modified broadband waveguide to coaxial line transitions placed on the cavity body, similar to those used for the DA$\Phi$NE collider RF cavities. Such a solution has a simple design that avoids the application of the ferrite materials under the ultra-high vacuum and dissipates the HOM power on the external loadings. Different from DA$\Phi$NE with a single cavity per ring, where the damping waveguides are placed laterally on the cavity body, we consider the possibility of allocating the waveguides vertically. Since the modern synchrotron light sources require using more RF cavities to compensate for the synchrotron radiation losses, such a solution helps to save the occupied space when placing the cavities in a row next to each other. This paper describes the design optimization process and discusses the obtained results concerning the effectiveness of the HOM suppression and minimization of the impact of the transitions on the fundamental mode parameters.

      • 25
        Extraction of the reactor neutrino spectral distortion in the Double Chooz experiment

        Double Chooz was a reactor neutrino disappearance experiment operating between 2011 and 2018. Its primary purpose was precisely measuring the neutrino mixing angle $\theta_{13}$. The experimental setup consisted of two identical liquid scintillator detectors at average baselines of about 400 m and 1 km to two nuclear reactor cores in Chooz, France. The neutrinos were detected by measuring the inverse beta decay (IBD) signature, which consists of a prompt positron annihilation and a delayed neutron capture signal. The simultaneous measurement of the neutrino energy spectra with two detectors is used in a Poisson-based likelihood fit to obtain the neutrino mixing angle $\theta_{13}$. Deviations to the reactor neutrino model prediction are incorporated by considering systematic differences in both detector data sets. This technique can extract the infamous spectral distortion observed by all reactor neutrino experiments. This poster explains the extraction method and shows the deviations from the reactor neutrino prediction.

        Speaker: Philipp Soldin Not Supplied
      • 26
        Partition Pooling for Convolutional Graph Network Applications in Particle Physics

        Convolutional Graph Networks (CGN) can be used for effective parameter estimations and event classification based on sensor-level data. However, if applied to the static sensor arrangement of modern particle detectors, the CGN performance can be limited by the considerable number of sensors. A scheme analogous to conventional pooling on images that uses graph partitioning to create pooling kernels is presented. With partition pooling, successful image recognition architectures can be adopted to graph neural network applications in particle physics. These architectures often rely on dimensionality reduction via pooling, which also helps to reduce computational costs. The latter allows for deeper networks and more extensive hyperparameter optimizations. A CGN, including partition pooling, is compared with a similar network without pooling performing vertex reconstructions in an idealized neutrino detector. The pooling improves the performance and makes the network less susceptible to overfitting. Due to the lower computational resource requirements, it is feasible to construct a deeper network, which further improves the performance.

        Speaker: Markus Bachlechner
      • 27
        The KM3NeT Project

        Abstract. KM3NeT is a research infrastructure housing the next generation of Cherenkov neutrino telescopes. It consists of two detectors with similar technology currently under construction in the Mediterranean Sea: ARCA (off-shore Sicily, Italy) and ORCA (off-shore Toulon, France) dedicated to Astroparticle and Oscillation Research with Cosmics in the Abyss, respectively. ARCA will instrument 1 Gton of seawater, with the primary goal of detecting high energy cosmic neutrinos from distant astrophysical sources with energies between tens of GeV and PeV., while ORCA has a denser instrumentation in a smaller volume of few Mtons. ORCA will detect atmospheric neutrinos in the 1 - 100 GeV energy range, studying neutrino properties. In this poster we present the KM3NeT project, current status and expected performances on measurements of the neutrino oscillation parameters, the mass ordering, the diffuse neutrino flux and the search for supernovae.

        Speaker: Giorgi Kistauri (Tbilisi State University)
      • 28
        Recent results from the KM3NeT Experiment

        KM3NeT is a European research infrastructure project currently under construction
        at two locations in the Mediterranean Sea. The project aims to detect the neutrinos in the
        energy range from a few GeV up to a few PeV with two detectors: ORCA (Oscillation
        Research with Cosmics in the Abyss) for low energy neutrinos and ARCA (Astroparti-
        cle Research with Cosmics in the Abyss) for high energy neutrinos. ORCA detector is
        optimised for neutrino physics, whereas ARCA is designed for neutrino astronomy. This
        poster describes recent results from the KM3NeT experiment obtained with six deployed
        detection units of ARCA and ORCA, respectively. Although these configurations repre-
        sent a small fraction of final ORCA (115 detection units) and ARCA (2x115 detection
        units) telescopes, promising results have been obtained for neutrino oscillations and neu-
        trino astronomy.

        Speaker: Gogita Papalashvili (HEPI, TSU)
    • Session 8: Poster session