Conveners
WG3: Electroweak Physics and Beyond the Standard Model 1: Higgs Physics
- Wouter Deconinck
- Niki Saoulidou (National and Kapodistrian University of Athens (GR))
- Doreen Wackeroth (SUNY Buffalo)
WG3: Electroweak Physics and Beyond the Standard Model 2
- Niki Saoulidou (National and Kapodistrian University of Athens (GR))
- Wouter Deconinck
- Doreen Wackeroth (SUNY Buffalo)
WG3: Electroweak Physics and Beyond the Standard Model 3
- Wouter Deconinck
- Tobias Neumann
- Doreen Wackeroth (SUNY Buffalo)
- Niki Saoulidou (National and Kapodistrian University of Athens (GR))
WG3: Electroweak Physics and Beyond the Standard Model 4
- Wouter Deconinck
- Doreen Wackeroth (SUNY Buffalo)
- Marc-Andre Pleier (Brookhaven National Laboratory (US))
- Christophe Royon (The University of Kansas (US))
- Niki Saoulidou (National and Kapodistrian University of Athens (GR))
WG3: Electroweak Physics and Beyond the Standard Model 5
- Doreen Wackeroth (SUNY Buffalo)
- Niki Saoulidou (National and Kapodistrian University of Athens (GR))
- Wouter Deconinck
Description
Electroweak Physics and Beyond the Standard Model
A search for off-shell production of the Higgs boson using 139 fb−1 of 𝑝𝑝 collision data at √𝑠 = 13 TeV collected by the ATLAS detector at the Large Hadron Collider. The observable signature is a pair of on-shell 𝑍 bosons, with contributions both from the virtual Higgs boson and interference with other processes, and the two decay final states, 𝑍 𝑍 → 4ℓ and 𝑍 𝑍 → 2ℓ2𝜈 with ℓ = 𝑒 or 𝜇. The...
Combining measurements of many production and decay channels of the observed Higgs boson allows for the highest possible measurement precision for the properties of the Higgs boson and its interactions. These combined measurements are interpreted in various ways; specific scenarios of physics beyond the Standard Model are tested, as well as a generic extension in the framework of the Standard...
The discovery of the Higgs boson with the mass of 125 GeV confirmed the mass generation mechanism via spontaneous electroweak symmetry breaking and completed the particle content predicted by the Standard Model. Even though this model is well established and consistent with many experimental measurements, it is not capable of solely explaining some observations. Many extensions of the Standard...
The Standard Model predicts several rare Higgs boson decay channels, among which are the decays to a Z boson and a photon, to a low-mass lepton pair and a photon, and to a meson and photon. The observation of some of these decays could open the possibility of studying the CP and coupling properties of the Higgs boson in a complementary way to other analyses. In addition,...
With the large data set collected during Run 2 of the LHC, it is possible to measure precise Higgs Yukawa couplings and go beyond inclusive Higgs boson cross section measurements. Simplified template cross sections (STXS), which make use of several variables to divide up the phase space of the different Higgs boson production modes, and differential cross sections can be measured. The STXS...
Testing the Yukawa couplings of the Higgs boson to quarks and leptons is important to understand the origin of fermion masses. The talk presents several measurements in Higgs boson decays to two bottom quarks or two tau leptons, searches for Higgs boson decays to two charm quarks or two muons, as well as direct constraints of the charm-Yukawa coupling. The production of Higgs bosons in...
With the full Run 2 pp collision dataset collected at 13 TeV, very detailed measurements of Higgs boson properties can be performed using its decays into bosons. This talk presents measurements of Higgs boson properties using decays into bosons, including production mode cross sections and simplified template cross sections, as well as their interpretations.
Studies of the CP properties of the Higgs boson in various production modes and decay channels are presented. Limits on the mixing of CP-even and CP-odd Higgs states are set by exploiting the properties of diverse final states.
Latest results on Z boson measurements are presented using collision data collected by CMS up to now. Differential production cross section measurements on several observables will be discussed.
Precision measurements of the production cross-sections of W/Z boson at LHC provide important tests of perturbative QCD and information about the parton distribution functions for quarks within the proton. Extremely precise double-differential measurement of Z transverse momentum and rapidity at centre-of-mass energy of 8 TeV will be presented. Also, the transverse momentum of the W and Z...
Recent results on the EW sector from the CMS Collaboration will be presented.
The weak mixing angle is a probe of the vector-axial coupling structure of electroweak interactions. It has been measured precisely at the $Z$-pole by experiments at the LEP and SLD colliders, but its energy dependence above $𝑚_Z$ remains unconstrained.
In this contribution we propose to exploit measurements of Neutral-Current Drell-Yan at large invariant dilepton masses at the Large...
Precision theory predictions are crucial for interpreting LHC data. In
this talk, we present our public code and predictions for Drell-Yan
production up to the order N3LO, including transverse momentum
resummation up to N4LLp. We discuss the impact of these higher-order
corrections and compare them with experimental data. Furthermore, we
investigate the influence of N3LO parton...
In the Standard Model, the ground state of the Higgs field is not found at zero but instead corresponds to one of the degenerate solutions minimising the Higgs potential. In turn, this spontaneous electroweak symmetry breaking provides a mechanism for the mass generation of nearly all fundamental particles. The Standard Model makes a definite prediction for the Higgs boson self-coupling and...
Determining the CP property of the Higgs boson is important for a precision test of the Standard Model as well as for the search for new physics. We propose a novel jet substructure observable based on the azimuthal anisotropy in a linearly polarized gluon jet that is produced in association with a Higgs boson at hadron colliders, and demonstrate that it provides a new CP-odd observable for...
The large integrated luminosity collected by the ATLAS detector at the highest proton-proton collision energy provided by LHC allows to probe the presence of new physics that could enhance the rate of very rare processes in the SM. The LHC can therefore gain considerable sensitivity for Flavour Changing Neutral Current (FCNC) interactions of the top quark. In the SM, FCNC involving the...
The Drell-Yan lepton pair productions have been measured to an unprecedented precision level at the LHC. In companion, the theoretical calculations should reach the same level. However, a visible discrepancy among different next-to-next-to-leading order (NNLO) calculations has been discovered by both the CTEQ-TEA group and also by S. Alekhin~\emph{et al.} In this study, we carefully examine...
For the CTEQ-TEA Collaboration
We present predictions of the cross section of high-energy neutrino-nucleon scattering.
The calculations are based on CT18NNLO parton distribution functions, and their uncertainties. For the highest energies, we extrapolate the PDFs to small x according to several assumptions, which affect the uncertainties at such high energies.
The results can be applied...
Accurate theory calculations for neutrino-nucleus scattering rates are essential in the interpretation of neutrino experiments, from oscillation measurements to astroparticle physics at neutrino telescopes. In the deep-inelastic (DIS) regime, neutrino structure functions can be reliably evaluated in the framework of perturbative QCD (pQCD). However, large uncertainties affect these structure...
Recasting phenomenological Lagrangians in terms of SM effective field theory (SMEFT) provides a valuable means of connecting potential BSM physics at momenta well above the electroweak scale to experimental signatures at lower energies. We jointly fit the Wilson coefficients of SMEFT operators as well as the PDFs in an extension of the CT18 global analysis framework, obtaining self-consistent...
Measurements of multiboson production at the LHC probe the electroweak gauge structure of the Standard Model for contributions for anomalous gauge couplings. Processes involving quartic gauge couplings have become experimentally accessible at the LHC. We present recent ATLAS results of vector-boson scattering in the Zgamma channel, where the Z boson decays to neutrinos producing missing...
Vector boson scattering is a key production process to probe the electroweak symmetry breaking of the standard model, since it involves both self-couplings of vector bosons and coupling with the Higgs boson. If the Higgs mechanism is not the sole source of electroweak symmetry breaking, the scattering amplitude deviates from the standard model prediction at high scattering energy. Moreover,...
easurements of multiboson production at the LHC are important probes of the electroweak gauge structure of the Standard Model and give constraints on anomalous gauge boson couplings. In this talk we present recent ATLAS measurement of double-polarization in WZ events and highlight the first observation of simultaneous pair-production of longitudinally polarized vector bosons. We also show...
We study the potential of DIS measurements at the Large Hadron-electron Collider (LHeC) and the Electron-Ion Collider (EIC) to probe physics beyond the Standard Model. Our study is performed in the context of the Standard Model Effective Field Theory (SMEFT). We find that future measurements at both machines can improve existing SMEFT fits to precision electroweak data by resolving blind spots...
An overview of the latest NA62 results and the future prospect of the experiment are presented. The NA62 experiment at CERN collected the world’s largest dataset of charged kaon decays in 2016-2018, leading to the first measurement of the branching ratio of the ultra-rare $K^+ \rightarrow \pi^+ \bar\nu \nu$ decay, based on 20 candidates.
The radiative kaon decay $K^+ \rightarrow \pi^0 e^+ \nu...
The electron-ion collider (EIC) will be the first collider capable of simultaneously polarizing the spin of both the leptons and hadrons involved. This opens the possibility for measurements of the nucleon spin structure and Parity-Violating (PV) asymmetry in Deep Inelastic Scattering (DIS), for the first time, at a collider setting. At the meantime, it also calls for a complete derivation of...
To describe low-energy (anti)neutrino fluxes in modern coherent elastic neutrino-nucleus scattering experiments as well as high-energy fluxes in precision-frontier projects such as the Enhanced NeUtrino BEams from kaon Tagging (ENUBET) and the Neutrinos from STORed Muons (nuSTORM), we evaluate (anti)neutrino energy spectra from radiative muon, pion, and kaon decays at O($\alpha$) level and...
In the high energy heavy ion collisions the ions can act as intense sources of electromagnetic radiation, or in the language of particle physics, photon-photon collisions. This is in particular the case for so--called ultraperipheral collisions (UPCs), where the impact parameter separation of the ions is significantly larger than the range of QCD, with the ions remaining intact after the...
We present here the most recent $BABAR$ results on searches for new particles with masses below the electroweak scale predicted by many extensions of the Standard Model (SM). The results are based on the full data set of about 470 $\text{fb}^{-1}$ collected at the $\Upsilon(4S)$ resonance at the PEP-II collider, including a search for an Axion-Like Particle, $a$, produced in the...
New light resonances are a generic signature of models of new phenomena beyond the Standard Model. The diphoton final states provides a clean final state and provides sensitivity to a wide class of such signals, in particular axion-like particles (ALPs). Several results of several such searches, both inclusive and in association with other particles, will be presented.
Lorentz and CPT symmetry in the quark sector of the Standard Model are studied in the context of an effective field theory using ZEUS ep data. Symmetry-violating effects can lead to time-dependent oscillations of otherwise time-independent observables, including scattering cross sections. An analysis using five years of inclusive neutral-current deep inelastic scattering events corresponding...
Many new physics models predict the existence of resonances decaying into two bosons (W, Z, photon, or Higgs bosons) making these important signatures in the search for new physics. Searches for Vy, VV, and VH resonances have been performed in various final states. In some of these searches, jet substructure techniques are used to disentangle the hadronic decay products in highly boosted...
Various theories beyond the Standard Model predict new, long-lived particles with unique signatures which are difficult to reconstruct and for which estimating the background rates is also a challenge. Signatures from displaced and/or delayed decays anywhere from the inner detector to the muon spectrometer, as well as those of new particles with fractional or multiple values of the charge of...
Leptoquarks 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 B-physics anomalies observed at LHCb and flavour factories. The ATLAS experiment has a broad program of direct searches for leptoquarks, coupling to the first-, second- or third-generation particles....
Search for the lepton flavor violation and test of the lepton flavor universality are of great interest as a signature of the New Physics. Such decays can be searched using large amount of B and Upsilon mesons produced at Belle. We present our search for $B, B_s \to \ell\tau$, $B \to K\tau\ell$, $\Upsilon(nS) \to \ell\tau$. We also present our study on decays relevant to Lepton Flavor...
In recent years, discrepancies from standard-model predictions, which suggest violation of lepton-flavor universality, have emerged in multiple measurements of B meson decays. This talk reports on related, recent Belle II results on lepton-flavour universality and long-lived particles.
With the pp collision dataset collected at 13 TeV, detailed measurements of Higgs boson properties can be performed. The Higgs kinematic properties can be measured with increasing granularity, and interpreted to constrain beyond-the-Standard-Model phenomena. This talk presents the measurements of Higgs boson differential and fiducial cross sections with various decay modes, as well as their...
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 (SM) it could be produced at the LHC. The ATLAS Collaboration has developed a broad search program for DM candidates in final states with large missing transverse momentum produced in association...
Supersymmetry (SUSY) provides elegant solutions to several problems in the Standard Model, and searches for SUSY particles are an important component of the LHC physics program. This talk will present the latest results from SUSY searches conducted by the ATLAS experiment. The searches target multiple final states and different assumptions about the decay mode of the produced SUSY particles,...
A new search for supersymmetry targeting pair production of squarks or gluinos decaying to sleptons or W, Z with final stated with either two leptons (electrons or muons) with the same electric charge or at least three leptons is presented. The analysis uses 139 fb-1 of pp collision data at 13 TeV collected with the ATLAS detector during Run 2 of the Large Hadron Collider, and simplified...
The Precision Proton Spectrometer (PPS) is a new subdetector of CMS introduced for the LHC Run 2 and will continue to operate during LHC Run 3. PPS provides a powerful tool for the advancement of BSM searches. The talk will present recent results obtained with the PPS subdetector illustrating the unique sensitivity achieved using proton tagging.
Relativistic heavy-ion beams at the LHC are accompanied by a large flux of equivalent photons, leading to multiple photon-induced processes. This talk presents a series of measurements of dilepton production from photon fusion performed by the ATLAS Collaboration. Recent measurements of exclusive dielectron production in ultra-peripheral collisions (UPC) are presented. These processes provide...
Relativistic heavy-ion beams at the LHC are accompanied by a large flux of equivalent photons, leading to multiple photon-induced processes. This talk presents searches for physics beyond the standard model enabled by photon-photon processes in both di-tau and di-photon final states. The tau-pair production measurements can constrain the tau lepton's anomalous magnetic dipole moment (g-2), and...
