A fixed-target experiment at the LHC to measure the dipole moments of charmed baryons, and potentially the tau lepton, is presented. It is based on the phenomena of particle channeling and spin precession in bent crystals. The detector comprises a spectrometer for measuring the momentum of charged particles and a Cherenkov detector for particle identification. The tracking system integrates...
We propose here a set of new methods to directly detect light mass dark matter through its scattering with abundant atmospheric muons or accelerator beams. Firstly, we plan to use the free cosmic-ray muons interacting with dark matter in a volume surrounded by detectors such as RPC and GEM, to trace possible interaction between dark matter and muons. Secondly, we will interface our device with...
The identification of jets arising from heavy-flavor (bottom or charm) quarks is crucial for many analyses in CMS, such as in top quark and Higgs boson measurements. Heavy-flavor tagging algorithms rely on the kinematics of reconstructed charged particle tracks and secondary vertices. These algorithms are typically trained using simulations that are prone to mismodeling. Hence it is crucial to...
A search for light scalars decaying to two tau leptons at high transverse momentum is presented using data collected from proton-proton collisions at \sqrt{s} = 13 TeV during Run2 by the CMS experiment at the LHC, corresponding to an integrated luminosity of 138 fb^{-1}. The scalar candidates are identified and reconstructed using novel machine-learning techniques based on interaction...
We present a search for hadronically-decaying pair-produced vector-like quarks (T/B) in data collected by the CMS detector during the Run 2 data taking period. The analysis is performed using a Boosted Event Shape Tagger (BEST): a multi-class jet tagger optimized for the boosted heavy particle final state jets. We train a neural-net-based tagger to identify high momentum, large-radius jets as...
Thermalization of heavy quarks in the quark-gluon plasma (QGP) is one of the most promising phenomena for understanding the strong interaction. The energy loss and momentum broadening at low momentum can be well described by a stochastic process with drag and diffusion terms. Recent advances in quantum computing, particularly quantum amplitude estimation (QAE), promise a quadratic speed-up in...
The search for high-mass resonances is central to the LHC experiments, serving as a direct probe for physics beyond the standard model (SM). As the quest for discovering new resonances intensifies, there has been increasing focus on model-agnostic search strategies. While these methods are renowned for their universality, they often fall short in sensitivity when distinguishing potential...
In the high-luminosity era of the Large Hadron Collider, the instantaneous luminosity is expected to reach unprecedented values, resulting in up to 200 proton-proton interactions in a typical bunch crossing. To cope with the resulting increase in occupancy, bandwidth and radiation damage, the ATLAS Inner Detector will be replaced by an all-silicon system, the Inner Tracker (ITk). The innermost...
The ATLAS experiment in the LHC Run 3 is recording up to 3 kHz of fully-built physics collision events out of an LHC bunch crossing rate of up to 40 MHz, with additional rate dedicated to partial readout. A two-level trigger system selects events of interest to to cover a wide variety of physics while rejecting a high rate of background events.
The selection of events targets both generic...
Deep-learning-based algorithms have become essential for a large fraction of tasks in high-energy-physics (HEP) research, like the identification of jets originating from heavy quarks at the Compact Muon Solenoid (CMS) Experiment at the Large Hadron Collider (LHC) at CERN. Existing frameworks are often limited in capability and based on older software libraries by today’s industry...
Two-Higgs-doublet models come with an augmented parameter space which allows them to possibly solve some of the shortcomings of the Standard Model, and opens the window to a plethora of new phenomena to be discovered. The introduction of scalar-mediated tree-level flavour-changing neutral currents may be tackled with the imposition of extra symmetries on the model or, alternatively, by...
A search is conducted for boosted Higgs production in association with a vector boson (VH) in V(qq), H(bb) decay channel at the LHC proton-proton collider. This production mode grows in relative contribution to the total Higgs production cross section with p_{T}. The process is used to probe the VH coupling for signs of new physics at high energy scales. The result is based on the full 13 TeV...
The efficient identification of jets originating from heavy-flavour quarks is essential for many measurements in High-Energy Physics, such as Higgs boson and top quark measurements as well as searches for physics beyond the Standard Model. Nevertheless, differences between measured data and the simulation on which the algorithms were trained can cause performance deficits and prediction...
The CMS electromagnetic calorimeter (ECAL) is a homogeneous, hermetic calorimeter comprised of 75,848 lead tungstate (PbWO4) crystals which is optimized for measuring the transverse energy of electrons and photons during LHC collisions. ECAL forms trigger primitives consisting of transverse energy sums and other deposit characteristics which are fed to the CMS Level-1 (L1) trigger at the 40...
Studies have yielded strong evidence that a deconfined state of quarks and gluons, the quark--gluon plasma, is created in heavy-ion collisions. This hot and dense matter exhibits almost zero friction and a strong collective behavior. An unexpected collective behavior has also been observed in small collision systems. In this talk, the origin of collectivity in small collision systems, which is...
Combination of searches for the resonant production of Higgs boson pairs is performed in the bbbb, bbtautau, and bbyy decay channels using up to 139 fb^-1 of proton-proton collision data at a center-of-mass energy of 13 TeV recorded by the ATLAS detector at the LHC. No significant excess over the expected background was observed, and upper limits were set at the 95% confidence level on the...
The inner detector of the present ATLAS experiment has been designed and developed to function in the environment of the present Large Hadron Collider (LHC). For the next LHC upgrade to High Luminosity, the particle densities and radiation levels will exceed the current levels by a factor of ten. The instantaneous luminosity is expected to reach unprecedented values, resulting in up to 200...
The reconstruction of data from the CSC requires calibration data including electronic constants, such as gains and pedestals, timing constants used in triggering, and electronic channels and full chamber validity information. Theses calibration conditions, also called conditions data, are produced in dedicated calibration runs or dedicated studies taken between periods of data taking. This...
Baryon number (B) is a conserved quantity in the Standard Model and plays a major role in cosmology. This poster highlights an extension of the Standard Model where baryon number conservation is an integral feature of the theory through a new local $U(1)_{\rm B}$ gauge symmetry [arXiv:1304.0576 [hep-ph]]. The baryon number is not anomaly-free and cancellation of the anomalies leads to the...
Measurements of inclusive, differential cross-sections for the production of events with missing transverse momentum in association with jets in proton--proton collisions at √s=13 TeV are presented. The measurements are made with the ATLAS detector using an integrated luminosity of 140~fb and include measurements of dijet distributions in a region in which vector-boson fusion processes are...
The CMS trigger system is a two-tiered filter designed to reduce the information coming from the detector to a level that can be stored for later analysis. The first of these tiers is the hardware-based Level 1 Trigger (L1T), which quickly parses through events for interesting physics objects to reduce the 40 MHz event rate in the detector to a rate that can be transmitted to the next tier,...
The CMS trigger system is a two-tiered filter designed to reduce the information coming from the detector to a level that can be stored for later analysis. The first of these tiers is the hardware-based Level 1 Trigger (L1T), which quickly parses through events for interesting physics objects to reduce the 40 MHz event rate in the detector to a rate that can be transmitted to the next tier,...
The CMS Collaboration is host to nearly 6000 members from around the world, working together on a wide variety of research topics towards a better understanding of the fundamental processes that make up our universe. CMS is formed from over 250 institutes in 58 countries, as such bringing a wealth of diverse perspectives which enhance our science. The CMS Diversity and Inclusion Office has...
Current physics measurements at the LHC rely on event selection based on modularized objects, such as jets and leptons. While modern deep learning algorithms have significantly improved jet tagging capabilities, their uses have been largely separated from event-level selections. Conversely, the holistic event-level neural networks employed in current analyses use less sophisticated jet...
The ATLAS Collaboration has developed a variety of Education and Outreach activities designed to engage young minds at home and in the classroom. This material ranges from an original particle physics baby book to colouring books, onlne printable information sheets and a challenging Masterclass program using real data from LHC proton collisions. Here we present our most recent developments...
Communicating the science and achievements of the ATLAS Experiment is a core objective of the ATLAS Collaboration. This contribution will explore the range of communication strategies adopted, provide an overview of ATLAS’ digital communication platforms - including its website and social media - and evaluate their impact on target audiences. Lessons learned and best practices will be shared,...
The ATLAS Collaboration hosts several very popular programmes bringing visitors to our detector at CERN or remotely via video conference from remote locations around the planet. ATLAS physicists take advantage of year-end technical stops and long shutdowns to show off the world’s largest collider detector to local audiences via guided visits and to remote audiences via virtual visits....
Within the ATLAS Experiment the Prompt Lepton Isolation Tagger (PLIT) served as an essential tool to distinguish between prompt muons originating from the decays of W and Z bosons and non-prompt muons generated in the semi-leptonic decays of b- and c-hadrons. Its central role was to effectively mitigate the presence of fake and non-prompt leptons in various multi-lepton final state analyses...
The ATLAS Collaboration consists of more than 5000 members, from over 100 different countries. Regional, age and gender demographics of the collaboration are presented, including the time evolution over the lifetime of the experiment. In particular, the relative fraction of women is discussed, including their share of contributions, recognition and positions of responsibility, including...
The intense photon fluxes of relativistic nuclei provide an opportunity to study photonuclear interactions in ultra-peripheral collisions. Exclusive final states of vector mesons can be studied in the process γ + A → meson + A. The measurement of photoproduced π+π−π+π− final states in ultra-peripheral Pb–Pb collisions at √sNN = 5.02 TeV is presented for the first time. The cross section,...
Dark-showers offer a compelling collider signature for Hidden Valley models featuring a confining dark sector. Our work extends the investigation of these models to near-conformal theories where the running coupling, controlled by renormalization group equations (RGE), flows near to an infra-red fixed point. We establish a framework of two classes of RGE solutions which cover much of the...
Flavour-tagging is a critical component of the ATLAS experiment physics programme. Existing flavour tagging algorithms rely on several low-level taggers, which are a combination of physically informed algorithms and machine learning models. A novel approach presented here instead uses a single machine learning model based on reconstructed tracks, avoiding the need for low-level taggers based...
The role of diversity in advancing scientific research is undeniable. Achieving success in physics not only entails rigorous research but also involves collaboration, conference participation, and networking. Nevertheless, members of the LGBTQ+ community encounter unique challenges and obstacles that impede their progression within the field.
This poster spotlights the LGBTQ+ CERN group, a...
In preparation for the forthcoming High-Luminosity phase of the Large Hadron Collider, the ATLAS experiment is working on major upgrades to its detector systems to effectively accommodate the increase in radiation levels and track density. The foremost among these upgrades is the replacement of the current Inner Detector with the Inner Tracker (ITk).
The ITk consists of a Pixel Detector close...
We present a Graph Neural Network-based approach to the problem of classifying jets as originating from either top quarks or the hadronization of a quark or gluon. We use high-fidelity simulated samples from the CMS Open Data, constructing graph nodes from the hits on the various subdetector layers. We compare the GNN performance with other algorithms. Finally, we discuss the technical...
Searches for heavy neutral leptons (HNLs) produced in association with a charged lepton are presented, covering a mass range between 1 GeV and 1.5 TeV. Proton-proton collisions data recorded at 13 TeV with the CMS experiment and corresponding to an integrated luminosity of 138/fb are analyzed. One search strategy targets short-lived HNL scenarios and selects events with three charged leptons...
The search is performed in the framework of “The New Particle Search at the LHC” demonstrator of the REINFORCE project. The REINFORCE EU (Research Infrastructures FOR Citizens in Europe) was a three- year long SwafS project which engaged citizens in active collaboration with the scientists working in large research infrastructures across Europe. The overall aim was to bridge the gap between...
Operating in the Higgs factory mode and beyond at center-of-mass energies up to 1 TeV, ILC offers plethora of measurements in the Higgs sector to address open questions of the Standard Model of particle physics and cosmology. This will be discussed from the perspective of global fits and individual measurements of the Higgs properties, including its exotic and CP violating interactions as well...
In heavy ion collisions, jets are formed during the iniCal hard scaDering event and move through the quark gluon plasma (QGP) as it evolves. The evoluCon of the medium manifests itself on the jet via various jet-medium interacCons, modifying its substructure as compared to vacuum QCD. Recently the energy correlator observable has been shown to be a powerful method to decode correlaCons in pp...
The first inclusive and normalised differential cross sections measurements for the production of single top quarks in association with a W boson in proton-proton collisions at a centre-of-mass energy of 13.6 TeV are presented. The data used were recorded with the CMS detector during 2022. Events containing one muon and one electron in the final state are analysed. For the inclusive...
The Ridge behavior in high-multiplicity proton-proton collisions has been debated a lot since it was first discovered. However, small systems like proton-proton collisions are not enough to provide a hot and dense medium called Quark-Gluon Plasma (QGP) in which the Ridge behavior is explained with hydrodynamic flows. In this study, we devise the pure kinematic model on interaction between jet...
The success of the CMS physics program at the HL-LHC requires maintaining sufficiently low trigger thresholds to select processes of interest. With an average expected 200 pileup interactions, critical to achieve this goal is including tracking in the hardware-based L1 trigger. A 40 MHz silicon-based track trigger on the scale of the CMS detector has never been built. The main challenges of...
The LHCb (Large Hadron Collider Beauty) experiment will undergo its high-luminosity detector upgrade (known as Upgrade II) in the long shutdown 4 of the LHC (2033-2034) to operate at a maximal instantaneous luminosity of $\rm 1.5~\times~10^{34}{cm}^{-2}{s}^{-1}$ in Runs 5 and 6, ten times higher than in previous data taking periods. This increase in instantaneous luminosity poses a challenge...
Long-lived particles are a compelling direction to search for physics beyond the Standard Model, and implementing dedicated long-lived particle (LLP) triggers provides an excellent avenue to expand experimental coverage into this challenging parameter space. We present a novel Compact Muon Solenoid (CMS) Level-1 LLP trigger that exploits the Run 3 upgrade of the Hadron Calorimeter (HCAL),...
This study presents novel measurements of isolated-prompt-photon production in pp collisions at 13 TeV using the ATLAS detector at the LHC . The analysis explores extended phase-space regions, focusing on differential cross sections with respect to photon transverse energy (E_T) and pseudorapidity (eta). Photon isolation criteria were applied. Additionally, the study investigated the...
In recent years, there has been a resurgence of interest in energy-energy correlators (EECs) for the study of hadronic collisions at both the LHC and RHIC. Measurements of EECs of particles within jets offer a clear separation of scales that is useful for studying both perturbative and non-perturbative QCD in the collinear limit. This poster presents recent EEC results from the archived ALEPH...
A measurement of the partial decay width of the Z boson into invisible particles with the ATLAS detector at the LHC is presented, using an integrated luminosity of 37 fb-1 of proton-proton data collected at a centre-of-mass energy of 13 TeV. Events with missing transverse momentum associated with at least one highly energetic jet are selected to construct ratios of invisible Z boson decays to...
During Long Shutdown 3 of the LHC, the ATLAS detector will undergo substantial upgrades to prepare for data taking at the future HL-LHC. This includes a replacement of its inner detector with a fully silicon tracker called the ITk, composed of pixel and strip sub-detectors. During the pre-production phase of the ITk strips detector, it was discovered that thermal cycling modules after mounting...
As the community transitions to the HL-LHC era, high-statistics simulations become increasingly important for precision phenomenological hypothesis testing. Reweighting Monte Carlo samples can increase the effective computational efficiency of simulation by allowing an ensemble of generated events to be reinterpreted as though it were obtained using different input parameters. Each stage of...
Determining the structure of protons and nuclei at high energy is one of central goals of the heavy-ion collisions and the future Electron-Ion Collider (EIC). We fisrt use Bayesian inference within the color glass condensate framework to extract the proton shape fluctuations from HERA exclusive vector meson production data at xp = 1.7*e-3. With this input, we employ the JIMWLK evolution for...
Muon reconstruction performance plays a crucial role in the precision and sensitivity of the LHC data analysis of the ATLAS experiment. Di-muon J/Psi and Z resonances are used to calibrate to per-mil accuracy the detector response for muons. This talk aims to provide an overview and the current status of the Muon Momentum Calibration within the ATLAS detector, thus the study of the procedure...
The observation of WWγ production in proton-proton collisions at a center-of-mass energy of 13 TeV with an integrated luminosity of 138 fb−1 is presented. The observed (expected) significance is 5.6 (4.7) standard deviations. Events are selected by requiring exactly two leptons (one electron and one muon) of opposite charge, moderate missing transverse momentum, and a photon. The measured...
Vertex reconstruction typically involves two steps: clustering reconstructed tracks into vertex candidates, or seeds, and fitting the vertex candidates to obtain vertex parameters. Secondary vertices are used in the identification, or tagging, of displaced jets originating from b and c quark hadronization, and in the tagging of soft jets with low transverse momenta. During the Run 2...
ATLAS Open Data for Education delivers proton-proton collision data from the ATLAS experiment at CERN to the public along with open-access resources for education and outreach. To date ATLAS has released a substantial amount of data from 8 TeV and 13 TeV collisions in an easily-accessible format and supported by dedicated documentation, software, and tutorials to ensure that everyone can...
The Large Hadron Collider will undergo a luminosity upgrade targeting a peak instantaneous luminosity ranging from 5–7.5×1034 cm−2s−1. The ambitious goal of the High Luminosity LHC is to achieve a total of 3000–4000 fb−1 of proton-proton collisions at a center-of-mass energy of 13–14 TeV by 2029. To cope with such challenging environmental conditions, the outer tracker of the CMS experiment...
The Tile Calorimeter (TileCal) is a sampling hadronic calorimeter covering the central region of the ATLAS experiment, with steel as absorber and plastic scintillators as active medium. The scintillators are read-out by the wavelength shifting fibres coupled to the photomultiplier tubes (PMTs). The analogue signals from the PMTs are amplified, shaped, digitized by sampling the signal every 25...
The New Small Wheel upgrade of the Muon Spectrometer was the largest Phase-1 upgrade project of the ATLAS detector. Two detector technologies—MicroMegas (MM) detectors and small Thin Gap Chambers (sTGCs)—were installed in the first station of the Muon Spectrometer endcap system in order to facilitate precision tracking and reduce the Level-1 trigger rate in anticipation of the increased...
The electromagnetic calorimeter (ECAL) of the CMS detector is homogenous, fine-grained detector made of scintillating lead-tungstate crystals. The CMS ECAL was designed to provide excellent energy resolution for electrons and photons and was crucial in the discovery of the Higgs boson. The good performance of ECAL continues to be important for many CMS physics analyses. The precise alignment...
The anomalous Higgs boson couplings, including the coupling of HHVV is measured in Vector Boson Scattering Processes using proton-proton collision data samples with center-of-mass energy √s = 13TeV during 2016, 2017 and 2018, corresponding to a total integrated luminosity of 138 /fb
The vector boson scattering is very important to understand the electroweak sector in particle physics which allows us to test the prediction of the standard model(SM) to a high precision as well as investigate beyond-the-standard model(BSM)\
My poster will include a search for a VBS production of two jets in association with two Z bosons at $\sqrt{s}=13$. The decay channel with two leptons...
Quantum entanglement, a fundamental feature of quantum mechanics, has emerged as a powerful tool that has significantly impacted various areas of physics. Notably, the quantification of entanglement through entanglement entropy has played a crucial role in advancing our understanding of diverse phenomena. In this study, we investigate the presence of quantum entanglement within the HZZ*...
Unstable long-lived particles with lifetime above 100 picoseconds occur in the Standard Model (SM) and show up in many of their extensions. They are, however, challenging to reconstruct and trigger at the LHC due to their very displaced decay vertices that often are located outside the vertex locator systems. The new fully software-based trigger system of the LHCb experiment for Run 3 onwards...
A search for the resonant production of a heavy scalar X decaying into a Higgs boson and a new lighter scalar S, through the process X -> S(bb)H(yy), where the two photons are consistent with the Higgs boson decay, is performed. The search is conducted using 140 fb-1 of LHC Run 2 data recorded by ATLAS. The search is performed for 170 GeV <=mX <= 1000 GeV and 15 GeV <= mS <= 500 GeV....
A search for the standard model Higgs boson (H) production with large transverse momentum (pT > 200 GeV) is presented. The search is performed with √s = 13 TeV proton- proton collision data collected by the CMS experiment at the CERN LHC during 2016–2018, corresponding to an integrated luminosity of 138 fb−1.
Among the several models proposed to explain the nature of Dark Matter (DM), several scenarios predict the existence of a larger Dark Sector. In this context, a new strongly-coupled, SU(2) dark flavour symmetry conserving model can be theorized as the ???dark??? counterpart of Standard Model QCD, leading to composite dark mesons or baryons as possible DM candidates. The vector-like fermions of...
A search for pair production of scalar and vector leptoquarks each decaying to a muon and a bottom quark is presented, using proton-proton collision data collected at √S=13 TeV with the CMS detector at the CERN LHC, corresponding to an integrated luminosity of 138 fb−1. No excess above standard model expectation is observed, and scalar (vector) LQs with masses less than 1810 (2120) GeV are...
A search for light scalars decaying to two tau leptons at high transverse momentum is presented using data collected from proton-proton collisions at \sqrt{s} = 13 TeV during Run2 by the CMS experiment at the LHC, corresponding to an integrated luminosity of 138 fb^{-1}. The scalar candidates are identified and reconstructed using novel machine-learning techniques based on interaction...
Presented here is an inclusive search for long-lived particles decaying to a pair of displaced muons. This search analyzes data collected in 2022 by the CMS experiment at the CERN LHC in proton-proton collisions at √s=13.6 TeV, adding up to an integrated luminosity of 36.6 fb−1. The experimental signature is a pair of oppositely charged muons originating from a common secondary vertex...
A search for low-mass narrow vector resonances decaying into quark-antiquark pairs at high transverse momentum is presented. The analysis is based on data collected in Run 2 with the CMS detector at the LHC in proton-proton collisions at \sqrt{13} TeV. Signal candidates are reconstructed as large-radius jets and identified using the ParticleNet algorithm. This analysis presents the most...
A search for non-resonant Higgs boson pair (HH) production is presented, in which one of the Higgs bosons decays to a b-quark pair (bb) and the other decays to WW, or ZZ, or tau+tau- , with in each case a final state with two leptons + neutrinos. Both gluon-gluon fusion and vector boson fusion are considered as production modes. Data recorded by the ATLAS detector in proton-proton collisions...
This is a first search for pair production of vector like tops, each decaying to a new scalar and a Standard Model (SM) top, with a consequent all-hadronic SM top decay. The signal region is optimized for a diphoton decay of one scalar, with the other treated inclusively. The final state exploits a clean experimental signature of two photons with two large-radius top-induced jets. This exotic...
This poster presents the search for a new Z' resonance decaying into a pair of dark quarks which hadronise into dark hadrons before promptly decaying back as Standard Model particles. This analysis is based on proton-proton collision data recorded at 13 TeV center of mass energy with the ATLAS detector at the Large Hadron Collider between 2015 and 2018, corresponding to an integrated...
Results are presented from a search for supersymmetry in events with a single electron or muon, and multiple hadronic jets. The data corresponds to a sample of proton-proton collisions at √s=13 TeV with an integrated luminosity of 138 fb^−1, recorded by the CMS experiment at the LHC.
The search targets gluino pair production, where the gluinos decay into the lightest supersymmetric particle...
A search for Drell Yan production of leptoquarks is performed using proton-proton collision data collected at √s = 13 TeV using the full Run-2 dataset with the CMS detector at the LHC, CERN. The data corresponds to an integrated luminosity of approximately 137 fb−1 . The search spans scalar and vector leptoquarks that couple up and down quarks to electrons and muons. Dielectron and dimuon...
A search for Drell Yan production of leptoquarks is performed using proton-proton collision data collected at √s = 13 TeV using the full Run-2 dataset with the CMS detector at the LHC, CERN. The data corresponds to an integrated luminosity of approximately 137 fb−1 . The search spans scalar and vector leptoquarks that couple up and down quarks to electrons and muons. Dielectron and dimuon...
The first dedicated LHC search for pair production of vector-like electrons and muons is presented. The analysis is based on a dataset of proton-proton collisions at sqrt(s)=13 TeV recorded with the ATLAS detector during Run 2 of the LHC, corresponding to an integrated luminosity of 140 fb-1. Events are categorised into channels based on the multiplicity of light charged leptons (electrons or...
This search for superpartner particles in events with leptonically decaying W and Z bosons and a multiplicity of jets, including up to two bottom quark jets, is the first search of its kind at the LHC. The sought out signature arises from weak production of a chargino-neutralino pair with cascade decays to two neutralinos, that each decay through hadronic R-parity violating interactions to...
This talk presents the results of a direct search for lepton-flavour-violating decays of the Higgs boson into e tau and mu tau final states with the ATLAS detector at the LHC with Run 2 data. Both leptonically and hadronically decaying tau leptons are included and two different background estimation techniques are employed: a MC-template method, based on data-corrected simulation samples, and...
Extensions of the Standard Model often feature heavy, charged, long-lived particles. These particles are expected to move significantly slower than the speed of light as they traverse the detector. The identification of such slow-moving charged particles can be made using measurements of ionization energy loss along a track. Specific ionization energy loss (dE/dx), converted into $\beta\gamma$...
The High Luminosity LHC will require upgrades to the ATLAS detector’s Level-0 (L0) muon trigger to cope with the increased luminosity. The Level-0 muon trigger will incorporate high precision hits from the Monitored Drift Tube chambers (MDTs) for the first time. The MDT Trigger Processor (MDTTP) uses the MDT hits to reconstruct muon tracks. This results in a reduction of the L0 trigger rate...
The Higgs boson self-coupling is one of the most vital measurements among the studies of Higgs boson properties, and such coupling can be measured in the non-resonant di-Higgs production. The cross-section of this channel, as predicted by the standard model (SM), is at O(fb), however, di-Higgs production can be promoted significantly in many beyond the SM (BSM) theories, e.g., through an...
The high luminosity phase of the LHC (HL-LHC) opens up new windows for exciting discoveries but also brings about new challenges due to the high pileup environment of approximately 200 simultaneous interactions per collision. Precise measurements of track and vertex timing can efficiently mitigate these pileup effects. Therefore, the CMS detector will be upgraded with a MIP timing detector...
This includes the development of custom preamplifiers and shapers with low noise and excellent linearity, a new ADC chip with two gains and new calibration boards with excellent non-linearity and non-uniformity between all calorimeter channels. New ATCA compliant signal processing boards equipped with FPGAs and high-speed links receiving the detector data and performing energy and time...
Monte Carlo Simulation data for the CMS experiment are produced using two different software chains. Full Simulation, is a precise tool based on Geant4 detector simulation. The other tool, Fast Simulation, provides a faster but still reliable tool and is based on parametric particle-material interactions. Full Simulation for the LHC Run-3 has shown significant computing performance...
This poster presents the reconstruction of missing transverse momentum (MET) in proton-proton collisions, at a center-of-mass energy of 13 TeV. This is a challenging task involving many detector inputs, combining fully calibrated electrons, muons, photons, hadronically decaying tau-leptons, hadronic jets, and soft activity from remaining tracks. Possible double counting of momentum is avoided...
The LHCb experiment aims to collect a dataset of 300 fb-1 in its high−luminosity phase. Such an objective calls for challenging upgrades of all the detector systems to successfull y operate at a peak luminosity of 1.5 x 10$^{34}$ cm$^{-2}$ s$^{-1}$. The future electromagnetic calorimeter, named PicoCal, will have to face a high radiation dose and mitigate a harsh occupancy, keeping the current...
The MIP Timing Detector (MTD) is a new sub-detector planned for the phase-2 upgrade of the Compact Muon Solenoid (CMS) experiment at CERN. The MTD will provide new and unique capabilities to CMS by measuring the time-of-arrival of minimum ionizing particles with a resolution of 30-60 ps. This information will help disentangle ~200 nearly simultaneous pileup interactions occurring in each bunch...
Unfolding detector distortions in experimental data is critical for enabling precision measurements in high-energy physics. However, traditional unfolding methods face challenges in scalability, flexibility, and dependence on simulations. We introduce a novel universal unfolding approach using conditional denoising diffusion probabilistic models (cDDPM). By modeling only the conditional...
The Tile Calorimeter (TileCal) is the hadronic calorimeter covering the central region of the ATLAS experiment. The High-Luminosity phase of LHC, delivering five times the LHC nominal instantaneous luminosity, is expected to start in 2029. TileCal will require new electronics to meet the requirements of a 1 MHz trigger, higher ambient radiation, and to ensure better performance under high...
The ATLAS pp physics program at the High Luminosity LHC (HL-LHC) requires precision luminosity measurement with systematic control better than 1% during operation with up to 200 simultaneous interactions per crossing. ATLAS will feature several luminosity detectors but at least one of them must be both calibratable in the van der Meer scans at low luminosity and able to maintain accuracy at...
Decay-time-dependent $C\!P$-violation effects in transitions of neutral $B$ mesons to $C\!P$-eigenstates can be visualised by oscillations in the asymmetry, as a function of decay time, between decay yields from mesons tagged as initially having $\bar{B}$ or $B$ flavour.
Such images, for example for $B^0 \to J/\psi K_S$ decays where the magnitude of the oscillation is proportional to...
