Conveners
Beyond the Standard Model: Session I - Premiere
- Alexandre Sousa (University of Cincinnati)
- Mia Tosi (Università degli Studi di Padova & INFN)
Beyond the Standard Model: Session II - Premiere
- Michal Malinský (IPNP, Charles University, Prague)
- Mia Tosi (Università degli Studi di Padova & INFN)
Beyond the Standard Model: Session III - Premiere
- Yu Nakahama Higuchi (Nagoya University (JP))
- Michal Malinský (IPNP, Charles University, Prague)
Beyond the Standard Model: Session IV - Premiere
- Alexandre Sousa (University of Cincinnati)
- Yu Nakahama Higuchi (Nagoya University (JP))
Beyond the Standard Model: Session II - Replay
- There are no conveners in this block
Beyond the Standard Model: Session I - Replay
- There are no conveners in this block
Beyond the Standard Model: Session III - Replay
- There are no conveners in this block
Beyond the Standard Model: Session IV - Replay
- There are no conveners in this block
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.
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}...
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...
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...
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,...
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...
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...
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...
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...
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...
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...
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
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.
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...
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...
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....
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.
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...
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...
The LHeC and the FCC-eh offer fascinating, unique possibilities for discovering BSM physics in DIS, both due to their large centre-of-mass energies and high luminosities. In this talk we will review most recent studies as presented in the 2020 LHeC White Paper. We will show the prospects for observing extensions of the Higgs sectors both with charged and neutral scalars, anomalous Higgs...
The E989 Muon $g-2$ Experiment at Fermilab aims to measure the muon magnetic anomaly, $a_\mu$, more precisely than the previous experiment at Brookhaven National Laboratory. There stands a greater than 3 standard deviations discrepancy between the Brookhaven measurement of $a_\mu$ and the theoretical value predicted using the Standard Model. The Fermilab experiment seeks to either resolve or...
The Muon $g-2$ Experiment at Fermilab measures the anomalous magnetic moment of the muon, $a_{\mu}$, with improved precision compared to the previous experiment at Brookhaven National Lab (BNL).
The value of $a_{\mu}$ from BNL currently differs from the Standard Model prediction by $\sim 3.6$ standard deviations or higher, suggesting the potential for new physics and therefore, motivating a...
The precision measurement of the anomalous magnetic moment of the muon presently exhibits a 3.5σ discrepancy with the Standard Model (SM) prediction. In the next few years this measurement will reach an even higher precision at Fermilab and J-PARC. While the QED and electroweak contributions to the muon g-2 can be determined very precisely, the leading hadronic (HLO) correction is affected by...
The observed muon anomalous magnetic moment deviates from the Standard
Model (SM) predictions. There are two scalar leptoquarks with simultaneous cou-
plings to the quark-muon pairs of both chiralities that can singly explain this discrepancy. We discuss an alternative mechanism that calls for mixing of two scalar leptoquarks of the same electric charge through the interaction with the Higgs...
New sources of CP violation, beyond the known sources in the standard model (SM), are required to explain the baryon asymmetry of the universe. Measurement of a non-zero permanent electric dipole moment (EDM) of fundamental particles, such as in an electron or a neutron, or nuclei or atoms can help us gain a handle on the sources of CP violation, both in SM and beyond. Multiple mechanisms...
We are interested in probing CP Violation (CPV) in photon-photon interactions. Such interactions, effectively described by operators of the form $FFF\tilde{F}$, have yet to be directly constrained experimentally, and could point to new sources of CPV beyond the Standard Model (SM). One possible mediator of CP-violating photon-photon interactions could be the relaxion, which is theoretically...
The electric dipole moment (EDM) of the neutron is a strong probe of CP violation beyond the Standard Model. In particular, its value could reveal information on baryogenesis. We report the latest result from the nEDM collaboration, which operates an experiment to measure the neutron EDM at the Paul Scherrer Institute using Ramsey’s method of separated oscillating magnetic fields with...
Searches for new resonances whose decays contain top quarks and/or b-quarks cover a wide range of beyond the Standard Model (SM) physics, such as generic heavy vector resonances or vector like quarks. These searches offer great potential to reduce SM backgrounds but also significant challenges in reconstructing and identifying the decay products as well as modelling the remaining background....
We present an overview of searches for new physics with top and bottom quarks in the final state, using proton-proton collision data collected with the CMS detector at the CERN LHC at a center-of-mass energy of 13 TeV. The results cover non-SUSY based extensions of the SM, including heavy gauge bosons or excited third generation quarks. Decay channels to vector-like top partner quarks, such as...
The upper bounds that the LHC measurements searching for heavy resonances beyond the Standard model set on the resonance production cross sections are not universal. They depend on various characteristics of the resonance under consideration, and their validity is also limited by the assumptions and approximations applied to their calculations. The bounds are typically used to derive the mass...
In extensions of two Higgs doublet models with vectorlike quarks, the decays of vectorlike quarks may be easily dominated by cascade decays through charged or neutral Higgs bosons leading to signatures with 6 top or bottom quarks. Since top quark decays also contain bottom quarks, the 6 bottom quarks in final states is a common signature to a large class of possible decay chains. We present a...
Many extensions of the standard model, including theories of Higgs-portal, gauge-portal , dark matter, heavy neutrinos, and supersymmetry predict new particles with long lifetimes, such that the position of their decay is measurably displaced from their production vertex. This talk presents latest results from searches for long-lived particles in CMS using the full Run-II data-set collected at the LHC.
Many theories beyond the Standard Model (BSM) predict unique signatures which are difficult to reconstruct and for which estimating the background rates is also a challenge. These signature include fractionally charged, highly ionizing and a wide range of proposed long-lived particles. These striking signatures are explored with the ATLAS detector using 13 TeV pp data, covering displaced...
The MicroBooNE experiment consists of a 50 m^3 active volume liquid argon time projection chamber (TPC) that sits 470 m from an 8 GeV proton beam on a beryllium target, and 690 m from a 120 GeV proton-on-graphite fixed target. These high-intensity beams may be creating a large flux of neutral long-lived particles (LLPs) with masses in the few-hundred MeV range, that are decay products of kaons...
Various SUSY scenarios lead to signatures with long-lived particles, such that the decay of the new particle is at a significant distance from the collision point. These signatures provide interesting technical challenges due to their special reconstruction requirements as well as their unusual backgrounds. This talk will present recent results in long-lived SUSY searches using ATLAS Run 2 data.
The magnetic monopole-antimonopole pair production, and their bound state, are estimated for colliders, focusing mainly in ALICE. The calculation is based on Dirac´s theory and considers photon fusion and Drell-Yan, using the mass range from 300 GeV up to 3 TeV. The number of expected events is given considering LHC energies and luminosity. In case of pp collisions, the higher contribution to...
The unprecedented collision energy of the LHC has opened up a new a new discovery frontier, where a theory underlying the Standard Model may yet be revealed. Now that the Higgs boson - the last piece of the Standard model puzzle - has apparently been discovered, the search for such new phenomena has assumed a key importance. However, the LHC has been running for several years and no signals...
Leptoquarks are hypothetical color-triplet bosons, which carry both baryon and lepton quantum numbers and have fractional electric charge. They are predicted by many extensions of the standard model, such as theories invoking grand unification, technicolor, or compositeness. Third-generation scalar LQs have recently received considerable theoretical interest, as their existence can explain the...
Leptoquarks (LQ) are predicted by many new physics theories to describe the similarities between the lepton and quark sectors of the Standard Model and offer an attractive potential explanation for the lepton flavour anomalies observed at flavour factories. The ATLAS experiment has a broad program of direct searches for leptoquarks produced either in pairs or singly, coupling to the first-,...
In order to simultaneously account for both $R_{D^{(\ast)}}$ and
$R_{K^{(\ast)}}$ anomalies in $B$-decays, we consider an extension
of the Standard Model by a single vector leptoquark field, and study
how one can achieve the required lepton flavour non-universality,
starting from a priori universal gauge couplings. While the unitary
quark-lepton mixing induced by $SU(2)_L$...
High-precision HERA data corresponding to a luminosity of around 1 fb$^{-1}$ have been used in the framework of $eeqq$ contact interactions (CI) to set limits on possible high-energy contributions beyond the Standard Model to electron--quark scattering. Measurements of the inclusive deep inelastic cross sections in neutral and charged current $ep$ scattering were considered. The analysis of...
The Deep Underground Neutrino Experiment (DUNE) is an international project aiming at neutrino physics and astrophysics and a search for phenomena predicted by theories beyond the standard model. The excellent imaging capability of Liquid Argon Time Projection Chamber (LArTPC) technology, particle tracking and identification utilized in the Far Detector allow the experiment to achieve high...
The observed matter-antimatter asymmetry in the universe composes a serious challenge to our understanding of nature. BNV/LNV decay has been searched in many experiments to understand this large-scale observed fact. In the case of e+e- collision, few experiments are performed. Here we proposed to search BNV and LNV with the world largest J/psi data sets in e+e- c. The BNV and LNV channel...
Neutron-Anti-neutron ($n$-$\bar{n}$) oscillation is a baryon number violating process that requires physics beyond the Standard model. Future experiments at ESS and DUNE aim to either discover $n$-$\bar{n}$ oscillation or to put more stringent constraints on the oscillation time. We study the impact of such a discovery on different baryogenesis scenarios in an effective field theory...
The Belle II experiment at SuperKEKB, an asymmetric e+e- collider, aims at a total integrated luminosity of 50 ab-1, to pursue a rich program of Standard Model and Beyond the Standard Model physics. In its first year of operation, approximately 10 fb-1 were collected at the Upsilon(4S) resonance, with about 100 fb-1 expected by the end of 2020. This results in a sizeable sample of tau pairs,...
The LHCb detector at the LHC offers unique coverage of forward rapidities. The detector also has a flexible trigger that enables low-mass states to be recorded with high efficiency, and a precision vertex detector that enables excellent separation of primary interactions from secondary decays. This allows LHCb to make significant (and world-leading) contributions in these regions of phase...
We argue that the search for vector dark boson through $e^+e^-\to Z^{\prime}\gamma$ can determine the Lorentz structure of $Z^{\prime}l^+l^-$ couplings with the detection of leptonic decays $Z^{\prime}\to l^+l^-$. We assume a general framework that the vector dark boson interacts with ordinary fermions through vector and axial-vector couplings. As a consequence of Ward-Takahashi identity,...
In this talk, I will address the possibility that the nature of dark matter is associated with neutrino mass generation.
Focusing on an extension of the Standard Model where the light neutrino masses are generated radiatively, we study the properties of a dark matter candidate which is made stable by the same symmetry responsible for the radiative origin of neutrino masses. Also, the model...
Many theories beyond the Standard Model predict new phenomena, such as Z’, W’ bosons or heavy neutrinos, in final states with isolated, high-pt leptons (e/mu/nu). Searches for new physics with such signatures, produced either resonantly or non-resonantly, are performed using the ATLAS experiment at the LHC. The recent 13 TeV pp results will be reported.
We show how the $Z$ boson polarization can be used to study the $ZH$ production at future $e^+e^-$ colliders and at the LHC. We calculate the 8 independent polarization parameters of the spin-1 $Z$ boson which are sensitive to anomalous gauge-Higgs couplings, using $Z$ spin density matrix. By constructing angular asymmetries from the $Z$ boson decay leptons, which are related to the...
The smallness of neutrino masses, which together with neutrino oscillations could be pointing to physics beyond the standard model, can be naturally accommodated by the so-called “seesaw” mechanism, in which new Heavy Neutral majorana Leptons (HNL) are postulated. A model providing HNLs that incorporates the seesaw mechanism, while also providing a DM candidate and giving a possible...
The unique design of the LHCb detector, with a flexible trigger and a precision vertex detector, enables competitive or even world-best limits on the production of long-lived particles, particularly for low mass states and for states that have a short lifetime. Searches have been performed at LHCb in fully hadronic and semileptonic final states.
Extensions of the Standard Model that include vector-like quarks commonly also include additional particles that may mediate new production or decay modes. Using as example the Minimal Linear Sigma Model, that reduces to the minimal SO(5)/SO(4) Composite Higgs Model in a specific limit, we consider the phenomenology of vector-like quarks when a scalar singlet (s) is present. This new particle...
A summary of searches for heavy resonances with masses exceeding 1 TeV decaying into pairs or triplets of bosons is presented, performed on data produced by LHC pp collisions at $\sqrt{s}$ = 13 TeV and collected with the CMS detector during 2016, 2017, and 2018. The common feature of these analyses is the boosted topology, namely the decay products of the considered bosons (both electroweak W,...
Muonium is the bound state of a positive muon and an electron. Muonium Spectroscopy Experiment Using Microwave (MuSEUM) collaboration has been performing precise spectroscopy of the ground state muonium hyperfine structure (MuHFS) with high-intensity pulsed muon beam at Japan Proton Accelerator Research Complex (J-PARC). Our goal is a ten-fold improvement in precision of MuHFS compared to the...
Data from the LHC at 7, 8, and 13 TeV have so far yielded no evidence for new particles beyond the 125 GeV Higgs boson; in particular, there have been no signs of SUSY. However, the complementary nature of physics with e+e- collisions still offers many interesting scenarios in which SUSY can be discovered at the ILC. These scenarios take advantage of the capability of e+e- collisions to...
The Compact Linear Collider (CLIC) is a mature option for a future electron-positron collider operating at centre-of-mass energies of up to 3 TeV. CLIC would be built and operated in a staged approach with three centre-of-mass energy stages currently assumed to be 380 GeV, 1.5 TeV, and 3 TeV. A selection of results from recent studies will be presented showing that CLIC has excellent...
FASER is an approved small and inexpensive experiment designed to search for light, weakly-interacting particles during Run 3 of the LHC. Such particles may be produced in large numbers along the beam collision axis, travel for hundreds of meters without interacting, and then decay to standard model particles. To search for such events, FASER will be located 480 m downstream of the ATLAS IP in...
The SHiP Collaboration has proposed a general-purpose experimental facility operating in beam dump mode at the CERN SPS accelerator with the aim of searching for light, long-lived exotic particles of Hidden Sector models. The SHiP experiment incorporates a muon shield based on magnetic sweeping and two complementary apparatuses. The detector immediately downstream of the muon shield is...
Observation of neutral long-lived particle (LLP) can be the first sign for physics beyond the Standard Model at the LHC. These particles are invisible until they decay into detectable Standard Model particles some macroscopic distance away from the collision. Their existence is theoretically well motivated and can provide explanations to known unexplained phenomena such as Dark Matter, the...
One of the important goals of the proposed future e+e- collider experiments is the search for the dark matter particles using different experimental approaches. The most general search approach is based on the mono-photon signature, which is expected when production of the invisible final state is accompanied by a hard photon from initial state radiation. Analysis of the energy spectrum...
In many supersymmetric scenarios, heavy Beyond Standard Model particles would decay to multiple massive Standard Model bosons or top quarks. The subsequent decays of these Standard Model particles into leptons and/or jets may then occur with significant branching ratios and can populate the events recorded by the ATLAS detector. This talk presents ATLAS searches for coloured superparticles...
The most recent results for searches of pair production of charged and neutral electroweak SUSY particles are presented. The analyses are performed in the final states containing one or more leptons, and presence of a boosted Higgs boson. The results are based on proton-proton collisions recorded at sqrt(s) = 13 TeV with the CMS detector using the full Run 2 dataset of 137 fb-1.
The newest results for classic searches for the pair-production of supersymmetric top partners in final states with and without leptons with the CMS detector are presented. The analysis strategies are developed to cover different scenarios of heavy stop particles as well as those with stop mass close to the SM top particles. The results are based on proton-proton collisions recorded at sqrt(s)...
Naturalness arguments for weak-scale supersymmetry favour supersymmetric partners of the third generation quarks with masses light enough to be produced at the LHC. The ATLAS experiment has a variety of analyses devoted to stop and sbottom direct production exploiting novel reconstruction and analysis techniques. This talk presents recent results using the full Run 2 dataset from these...
Since the classic searches have not given any strong indication for new physics, more and more supersymmetry searches target the more difficult scenarios. This talk focuses on searches looking for signatures of stealth supersymmetry as well as those searches focusing on the scenarios with compressed mass spectra that require using dedicated tools. The results are based on proton-proton...
Analyses at the LHC are becoming increasingly sensitive to the direct production of electroweak SUSY particles, such as charginos, neutralinos, and sleptons, with important consequences on our understanding of dark matter and the naturalness of the Higgs mass. This talk will present the latest results from searches for electroweak SUSY production using data collected with the ATLAS experiment...
Updated results for electroweak production of SUSY particles at the LHC Run-II are given with NLO+NLL (next-to-leading-order plus next-to-leading-logarithmic) accuracy, consistently computed with novel PDFs with resummation-improved matrix elements.
A factorisation method is applied to exploit the smaller PDF uncertainty of the global PDF sets and to avoid complications arising in the...
Fiducial production cross-section measurements of Standard Model processes, in principle, provide constraints on new physics scenarios via a comparison of the predicted Standard Model cross-section and the observed cross-section. This approach received significant attention in recent years, both from direct constraints on specific models and the interpretation of measurements in the view of...
The apparent absence of superpartners at the LHC suggests that complex decays may be obscuring hints of their existence. To maximize sensitivity in the large datasets available from Run 2 of the LHC, searches for supersymmetric particles have adopted progressively more advanced analysis strategies. This presentation features several analyses that have been carried out by the ATLAS...
In this talk, we will talk about the application of Deep Learning models as a discriminant step to improve sensitivity at searches for new physics. Of particular interest, we will focus on the transferability of Deep Learning models, where a neural network trained to isolate a specific signal can still provide sensitivity when deriving upper limits on a different process. This is expanded to...
Many supersymmetric scenarios feature final states with non-standard final state objects. When considering compressed scenarios, involving sparticle spectra with small mass-splittings and decays to low-momentum leptons or jets, analyses depend on novel methods for the reconstruction of these very soft particles. This talk will review the application of innovative techniques, including soft...
We apply techniques from Bayesian generative probabilistic modelling to discover hidden features in jet substructure observables. We show that our method is able to discriminate between different unknown short distance physical processes in events at the LHC. In particular, we use a mixed membership model known as Latent Dirichlet Allocation to model the main features appearing during jet...
