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  1. Abstract

    Computing demands for large scientific experiments, such as the CMS experiment at the CERN LHC, will increase dramatically in the next decades. To complement the future performance increases of software running on central processing units (CPUs), explorations of coprocessor usage in data processing hold great potential and interest. Coprocessors are a class of computer processors that supplement CPUs, often improving the execution of certain functions due to architectural design choices. We explore the approach of Services for Optimized Network Inference on Coprocessors (SONIC) and study the deployment of this as-a-service approach in large-scale data processing. In the studies, we take a data processing workflow of the CMS experiment and run the main workflow on CPUs, while offloading several machine learning (ML) inference tasks onto either remote or local coprocessors, specifically graphics processing units (GPUs). With experiments performed at Google Cloud, the Purdue Tier-2 computing center, and combinations of the two, we demonstrate the acceleration of these ML algorithms individually on coprocessors and the corresponding throughput improvement for the entire workflow. This approach can be easily generalized to different types of coprocessors and deployed on local CPUs without decreasing the throughput performance. We emphasize that the SONIC approach enables high coprocessor usage and enables the portability to run workflows on different types of coprocessors.

     
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    Free, publicly-accessible full text available December 1, 2025
  2. A search for collective effects inside jets produced in proton-proton collisions is performed via correlation measurements of charged particles using the CMS detector at the CERN LHC. The analysis uses data collected at a center-of-mass energy ofs=13TeV, corresponding to an integrated luminosity of138fb1. Jets are reconstructed with the anti-kTalgorithm with a distance parameter of 0.8 and are required to have transverse momentum greater than 550 GeV and pseudorapidity|ηjet|<1.6. Two-particle correlations among the charged particles within the jets are studied as functions of the particles’ azimuthal angle and pseudorapidity separations (Δϕ*andΔη*) in a jet coordinate basis, where particles’η*,ϕ*are defined relative to the direction of the jet. The correlation functions are studied in classes of in-jet charged-particle multiplicity up toNchj100. Fourier harmonics are extracted from long-range azimuthal correlation functions to characterize azimuthal anisotropy for|Δη*|>2. For low-Nchjjets, the long-range elliptic anisotropic harmonic,v2*, is observed to decrease withNchj. This trend is well described by Monte Carlo event generators. However, a rising trend forv2*emerges atNchj80, hinting at a possible onset of collective behavior, which is not reproduced by the models tested. This observation yields new insights into the dynamics of jet evolution in the vacuum.

    <supplementary-material><permissions><copyright-statement>© 2024 CERN, for the CMS Collaboration</copyright-statement><copyright-year>2024</copyright-year><copyright-holder>CERN</copyright-holder></permissions></supplementary-material></sec> </div> <a href='#' class='show open-abstract' style='margin-left:10px;'>more »</a> <a href='#' class='hide close-abstract' style='margin-left:10px;'>« less</a> <div class="actions" style="padding-left:10px;"> <span class="reader-count"> Free, publicly-accessible full text available September 1, 2025</span> </div> </div><div class="clearfix"></div> </div> </li> <li> <div class="article item document" itemscope itemtype="http://schema.org/TechArticle"> <div class="item-info"> <div class="title"> <a href="https://par.nsf.gov/biblio/10552269-search-bottom-type-vectorlike-quark-pair-production-dileptonic-fully-hadronic-final-states-proton-proton-collisions" itemprop="url"> <span class='span-link' itemprop="name">Search for bottom-type vectorlike quark pair production in dileptonic and fully hadronic final states in proton-proton collisions at s=13  TeV</span> </a> </div> <div> <strong> <a class="misc external-link" href="https://doi.org/10.1103/PhysRevD.110.052004" target="_blank" title="Link to document DOI">https://doi.org/10.1103/PhysRevD.110.052004  <span class="fas fa-external-link-alt"></span></a> </strong> </div> <div class="metadata"> <span class="authors"> <span class="author" itemprop="author">Hayrapetyan, A</span> <span class="sep">; </span><span class="author" itemprop="author">Tumasyan, A</span> <span class="sep">; </span><span class="author" itemprop="author">Adam, W</span> <span class="sep">; </span><span class="author" itemprop="author">Andrejkovic, J W</span> <span class="sep">; </span><span class="author" itemprop="author">Bergauer, T</span> <span class="sep">; </span><span class="author" itemprop="author">Chatterjee, S</span> <span class="sep">; </span><span class="author" itemprop="author">Damanakis, K</span> <span class="sep">; </span><span class="author" itemprop="author">Dragicevic, M</span> <span class="sep">; </span><span class="author" itemprop="author">Hussain, P S</span> <span class="sep">; </span><span class="author" itemprop="author">Jeitler, M</span> <span class="sep">; </span><span class="author">et al</span></span> <span class="year">( <time itemprop="datePublished" datetime="2024-09-01">September 2024</time> , Physical Review D) </span> </div> <div style="cursor: pointer;-webkit-line-clamp: 5;" class="abstract" itemprop="description"> <p>A search is described for the production of a pair of bottom-type vectorlike quarks (<math display='inline'><mi>B</mi></math>VLQs) with mass greater than 1000 GeV. Each<math display='inline'><mi>B</mi></math>VLQ decays into a<math display='inline'><mi>b</mi></math>quark and a Higgs boson, a<math display='inline'><mi>b</mi></math>quark and a<math display='inline'><mi>Z</mi></math>boson, or a<math display='inline'><mi>t</mi></math>quark and a<math display='inline'><mi>W</mi></math>boson. This analysis considers both fully hadronic final states and those containing a charged lepton pair from a<math display='inline'><mi>Z</mi></math>boson decay. The products of the<math display='inline'><mi>H</mi><mo stretchy='false'>→</mo><mi>b</mi><mi>b</mi></math>boson decay and of the hadronic<math display='inline'><mi>Z</mi></math>or<math display='inline'><mi>W</mi></math>boson decays can be resolved as two distinct jets or merged into a single jet, so the final states are classified by the number of reconstructed jets. The analysis uses data corresponding to an integrated luminosity of<math display='inline'><mn>138</mn><mtext> </mtext><mtext> </mtext><msup><mi>fb</mi><mrow><mo>−</mo><mn>1</mn></mrow></msup></math>collected in proton-proton collisions at<math display='inline'><msqrt><mi>s</mi></msqrt><mo>=</mo><mn>13</mn><mtext> </mtext><mtext> </mtext><mi>TeV</mi></math>with the CMS detector at the LHC from 2016 to 2018. No excess over the expected background is observed. Lower limits are set on the<math display='inline'><mi>B</mi></math>VLQ mass at the 95% confidence level. These depend on the<math display='inline'><mi>B</mi></math>VLQ branching fractions and are 1570 and 1540 GeV for 100%<math display='inline'><mi>B</mi><mo stretchy='false'>→</mo><mi>b</mi><mi>H</mi></math>and 100%<math display='inline'><mi>B</mi><mo stretchy='false'>→</mo><mi>b</mi><mi>Z</mi></math>, respectively. In most cases, the mass limits obtained exceed previous limits by at least 100 GeV.</p> <sec><title/><supplementary-material><permissions><copyright-statement>© 2024 CERN, for the CMS Collaboration</copyright-statement><copyright-year>2024</copyright-year><copyright-holder>CERN</copyright-holder></permissions></supplementary-material></sec> </div> <a href='#' class='show open-abstract' style='margin-left:10px;'>more »</a> <a href='#' class='hide close-abstract' style='margin-left:10px;'>« less</a> <div class="actions" style="padding-left:10px;"> <span class="reader-count"> Free, publicly-accessible full text available September 1, 2025</span> </div> </div><div class="clearfix"></div> </div> </li> <li> <div class="article item document" itemscope itemtype="http://schema.org/TechArticle"> <div class="item-info"> <div class="title"> <a href="https://par.nsf.gov/biblio/10552270-search-resonance-decaying-boson-photon-proton-proton-collisions-sqrt-tev-using-leptonic-boson-decays" itemprop="url"> <span class='span-link' itemprop="name">Search for a resonance decaying to a W boson and a photon in proton-proton collisions at $$ \sqrt{s} $$ = 13 TeV using leptonic W boson decays</span> </a> </div> <div> <strong> <a class="misc external-link" href="https://doi.org/10.1007/JHEP09(2024)186" target="_blank" title="Link to document DOI">https://doi.org/10.1007/JHEP09(2024)186  <span class="fas fa-external-link-alt"></span></a> </strong> </div> <div class="metadata"> <span class="authors"> <span class="author" itemprop="author">Hayrapetyan, A</span> <span class="sep">; </span><span class="author" itemprop="author">Tumasyan, A</span> <span class="sep">; </span><span class="author" itemprop="author">Adam, W</span> <span class="sep">; </span><span class="author" itemprop="author">Andrejkovic, J W</span> <span class="sep">; </span><span class="author" itemprop="author">Bergauer, T</span> <span class="sep">; </span><span class="author" itemprop="author">Chatterjee, S</span> <span class="sep">; </span><span class="author" itemprop="author">Damanakis, K</span> <span class="sep">; </span><span class="author" itemprop="author">Dragicevic, M</span> <span class="sep">; </span><span class="author" itemprop="author">Hussain, P S</span> <span class="sep">; </span><span class="author" itemprop="author">Jeitler, M</span> <span class="sep">; </span><span class="author">et al</span></span> <span class="year">( <time itemprop="datePublished" datetime="2024-09-01">September 2024</time> , Journal of High Energy Physics) </span> </div> <div style="cursor: pointer;-webkit-line-clamp: 5;" class="abstract" itemprop="description"> <title>A<sc>bstract</sc>

    A search for a new charged particle X with mass between 0.3 and 2.0 TeV decaying to a W boson and a photon is presented, using proton-proton collision data at a center-of-mass energy of 13 TeV, collected by the CMS experiment and corresponding to an integrated luminosity of 138 fb1. Particle X has electric charge ±1 and is assumed to have spin 0. The search is performed using the electron and muon decays of the W boson. No significant excess above the predicted background is observed. The upper limit at 95% confidence level on the product of the production cross section of the X and its branching fraction to a W boson and a photon is found to be 94 (137) fb for a 0.3 TeV resonance and 0.75 (0.81) fb for a 2.0 TeV resonance, for an X width-to-mass ratio of 0.01% (5%). This search presents the most stringent constraints to date on the existence of such resonances across the probed mass range. A statistical combination with an earlier study based on the hadronic decay mode of the W boson is also performed, and the upper limit at 95% confidence level for a 2.0 TeV resonance is reduced to 0.50 (0.63) fb for an X width-to-mass ratio of 0.01% (5%).

     
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    Free, publicly-accessible full text available September 1, 2025
  3. Energy correlators that describe energy-weighted distances between two or three particles in a hadronic jet are measured using an event sample ofs=13TeVproton-proton collisions collected by the CMS experiment and corresponding to an integrated luminosity of36.3fb1. The measured distributions are consistent with the trends in the simulation that reveal two key features of the strong interaction: confinement and asymptotic freedom. By comparing the ratio of the measured three- and two-particle energy correlator distributions with theoretical calculations that resum collinear emissions at approximate next-to-next-to-leading-logarithmic accuracy matched to a next-to-leading-order calculation, the strong coupling is determined at theZboson mass:αS(mZ)=0.12290.0050+0.0040, the most preciseαS(mZ)value obtained using jet substructure observables.

    <supplementary-material><permissions><copyright-statement>© 2024 CERN, for the CMS Collaboration</copyright-statement><copyright-year>2024</copyright-year><copyright-holder>CERN</copyright-holder></permissions></supplementary-material></sec> </div> <a href='#' class='show open-abstract' style='margin-left:10px;'>more »</a> <a href='#' class='hide close-abstract' style='margin-left:10px;'>« less</a> <div class="actions" style="padding-left:10px;"> <span class="reader-count"> Free, publicly-accessible full text available August 1, 2025</span> </div> </div><div class="clearfix"></div> </div> </li> <li> <div class="article item document" itemscope itemtype="http://schema.org/TechArticle"> <div class="item-info"> <div class="title"> <a href="https://par.nsf.gov/biblio/10549912-search-long-lived-particles-decaying-cms-muon-detectors-proton-proton-collisions" itemprop="url"> <span class='span-link' itemprop="name">Search for long-lived particles decaying in the CMS muon detectors in proton-proton collisions at s=13  TeV</span> </a> </div> <div> <strong> <a class="misc external-link" href="https://doi.org/10.1103/PhysRevD.110.032007" target="_blank" title="Link to document DOI">https://doi.org/10.1103/PhysRevD.110.032007  <span class="fas fa-external-link-alt"></span></a> </strong> </div> <div class="metadata"> <span class="authors"> <span class="author" itemprop="author">Hayrapetyan, A</span> <span class="sep">; </span><span class="author" itemprop="author">Tumasyan, A</span> <span class="sep">; </span><span class="author" itemprop="author">Adam, W</span> <span class="sep">; </span><span class="author" itemprop="author">Andrejkovic, J W</span> <span class="sep">; </span><span class="author" itemprop="author">Bergauer, T</span> <span class="sep">; </span><span class="author" itemprop="author">Chatterjee, S</span> <span class="sep">; </span><span class="author" itemprop="author">Damanakis, K</span> <span class="sep">; </span><span class="author" itemprop="author">Dragicevic, M</span> <span class="sep">; </span><span class="author" itemprop="author">Hussain, P S</span> <span class="sep">; </span><span class="author" itemprop="author">Jeitler, M</span> <span class="sep">; </span><span class="author">et al</span></span> <span class="year">( <time itemprop="datePublished" datetime="2024-08-01">August 2024</time> , Physical Review D) </span> </div> <div style="cursor: pointer;-webkit-line-clamp: 5;" class="abstract" itemprop="description"> <p>A search for long-lived particles (LLPs) decaying in the CMS muon detectors is presented. A data sample of proton-proton collisions at<math display='inline'><msqrt><mi>s</mi></msqrt><mo>=</mo><mn>13</mn><mtext> </mtext><mtext> </mtext><mi>TeV</mi></math>corresponding to an integrated luminosity of<math display='inline'><mn>138</mn><mtext> </mtext><mtext> </mtext><msup><mi>fb</mi><mrow><mo>−</mo><mn>1</mn></mrow></msup></math>, recorded at the LHC in 2016–2018, is used. The decays of LLPs are reconstructed as high multiplicity clusters of hits in the muon detectors. In the context of twin Higgs models, the search is sensitive to LLP masses from 0.4 to 55 GeV and a broad range of LLP decay modes, including decays to hadrons,<math display='inline'><mi>τ</mi></math>leptons, electrons, or photons. No excess of events above the standard model background is observed. The most stringent limits to date from LHC data are set on the branching fraction of the Higgs boson decay to a pair of LLPs with masses below 10 GeV. This search also provides the best limits for various intervals of LLP proper decay length and mass. Finally, this search sets the first limits at the LHC on a dark quantum chromodynamic sector whose particles couple to the Higgs boson through gluon, Higgs boson, photon, vector, and dark-photon portals, and is sensitive to branching fractions of the Higgs boson to dark quarks as low as<math display='inline'><mn>2</mn><mo>×</mo><msup><mn>10</mn><mrow><mo>−</mo><mn>3</mn></mrow></msup></math>.</p> <sec><title/><supplementary-material><permissions><copyright-statement>© 2024 CERN, for the CMS Collaboration</copyright-statement><copyright-year>2024</copyright-year><copyright-holder>CERN</copyright-holder></permissions></supplementary-material></sec> </div> <a href='#' class='show open-abstract' style='margin-left:10px;'>more »</a> <a href='#' class='hide close-abstract' style='margin-left:10px;'>« less</a> <div class="actions" style="padding-left:10px;"> <span class="reader-count"> Free, publicly-accessible full text available August 1, 2025</span> </div> </div><div class="clearfix"></div> </div> </li> <li> <div class="article item document" itemscope itemtype="http://schema.org/TechArticle"> <div class="item-info"> <div class="title"> <a href="https://par.nsf.gov/biblio/10537333-constraints-anomalous-higgs-boson-couplings-from-its-production-decay-using-ww-channel-protonproton-collisions-sqrt-text-tev" itemprop="url"> <span class='span-link' itemprop="name">Constraints on anomalous Higgs boson couplings from its production and decay using the WW channel in proton–proton collisions at $$\sqrt{s} = 13~\text {TeV}$$</span> </a> </div> <div> <strong> <a class="misc external-link" href="https://doi.org/10.1140/epjc/s10052-024-12925-0" target="_blank" title="Link to document DOI">https://doi.org/10.1140/epjc/s10052-024-12925-0  <span class="fas fa-external-link-alt"></span></a> </strong> </div> <div class="metadata"> <span class="authors"> <span class="author" itemprop="author">Hayrapetyan, A</span> <span class="sep">; </span><span class="author" itemprop="author">Tumasyan, A</span> <span class="sep">; </span><span class="author" itemprop="author">Adam, W</span> <span class="sep">; </span><span class="author" itemprop="author">Andrejkovic, J W</span> <span class="sep">; </span><span class="author" itemprop="author">Bergauer, T</span> <span class="sep">; </span><span class="author" itemprop="author">Chatterjee, S</span> <span class="sep">; </span><span class="author" itemprop="author">Damanakis, K</span> <span class="sep">; </span><span class="author" itemprop="author">Dragicevic, M</span> <span class="sep">; </span><span class="author" itemprop="author">Hussain, P S</span> <span class="sep">; </span><span class="author" itemprop="author">Jeitler, M</span> <span class="sep">; </span><span class="author">et al</span></span> <span class="year">( <time itemprop="datePublished" datetime="2024-08-01">August 2024</time> , The European Physical Journal C) </span> </div> <div style="cursor: pointer;-webkit-line-clamp: 5;" class="abstract" itemprop="description"> <title>Abstract

    A study of the anomalous couplings of the Higgs boson to vector bosons, including$${\textit{CP}}$$CP-violation effects, has been conducted using its production and decay in the WW channel. This analysis is performed on proton–proton collision data collected with the CMS detector at the CERN LHC during 2016–2018 at a center-of-mass energy of 13 TeV, and corresponds to an integrated luminosity of 138$$\,\text {fb}^{-1}$$fb-1. The different-flavor dilepton$$({\textrm{e}} {{\upmu }})$$(eμ)final state is analyzed, with dedicated categories targeting gluon fusion, electroweak vector boson fusion, and associated production with a W or Z boson. Kinematic information from associated jets is combined using matrix element techniques to increase the sensitivity to anomalous effects at the production vertex. A simultaneous measurement of four Higgs boson couplings to electroweak vector bosons is performed in the framework of a standard model effective field theory. All measurements are consistent with the expectations for the standard model Higgs boson and constraints are set on the fractional contribution of the anomalous couplings to the Higgs boson production cross section.

     
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    Free, publicly-accessible full text available August 1, 2025
  4. A<sc>bstract</sc>

    Results are presented from a search for new physics in high-mass diphoton events from proton-proton collisions at$$ \sqrt{s} $$s= 13 TeV. The data set was collected in 2016–2018 with the CMS detector at the LHC and corresponds to an integrated luminosity of 138 fb1. Events with a diphoton invariant mass greater than 500 GeV are considered. Two different techniques are used to predict the standard model backgrounds: parametric fits to the smoothly-falling background and a first-principles calculation of the standard model diphoton spectrum at next-to-next-to-leading order in perturbative quantum chromodynamics calculations. The first technique is sensitive to resonant excesses while the second technique can identify broad differences in the invariant mass shape. The data are used to constrain the production of heavy Higgs bosons, Randall-Sundrum gravitons, the large extra dimensions model of Arkani-Hamed, Dimopoulos, and Dvali (ADD), and the continuum clockwork mechanism. No statistically significant excess is observed. The present results are the strongest limits to date on ADD extra dimensions and RS gravitons with a coupling parameter greater than 0.1.

     
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    Free, publicly-accessible full text available August 1, 2025
  5. A<sc>bstract</sc>

    Measurements of the charge-dependent two-particle angular correlation function in proton-lead (pPb) collisions at a nucleon-nucleon center-of-mass energy of$$ \sqrt{s_{\textrm{NN}}} $$sNN= 8.16 TeV and lead-lead (PbPb) collisions at$$ \sqrt{s_{\textrm{NN}}} $$sNN= 5.02 TeV are reported. The pPb and PbPb data sets correspond to integrated luminosities of 186 nb1and 0.607 nb1, respectively, and were collected using the CMS detector at the CERN LHC. The charge-dependent correlations are characterized by balance functions of same- and opposite-sign particle pairs. The balance functions, which contain information about the creation time of charged particle pairs and the development of collectivity, are studied as functions of relative pseudorapidity (∆η) and relative azimuthal angle (∆ϕ), for various multiplicity and transverse momentum (pT) intervals. A multiplicity dependence of the balance function is observed in ∆ηand ∆ϕfor both systems. The width of the balance functions decreases towards high-multiplicity collisions in the momentum region<2 GeV, for pPb and PbPb results. Integrals of the balance functions are presented in both systems, and a mild dependence of the charge-balancing fractions on multiplicity is observed. No multiplicity dependence is observed at higher transverse momentum. The data are compared withhydjet,hijing, andamptgenerator predictions, none of which capture completely the multiplicity dependence seen in the data. The comparison of results with different center-of-mass energies suggests that the balance functions become narrower at higher energies, which is consistent with the idea of delayed hadronization and the effect of radial flow.

     
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    Free, publicly-accessible full text available August 1, 2025
  6. Abstract

    A measurement is presented of a ratio observable that provides a measure of the azimuthal correlations among jets with large transverse momentum$$p_{\textrm{T}}$$pT. This observable is measured in multijet events over the range of$$p_{\textrm{T}} = 360$$pT=360$$3170\,\text {Ge}\hspace{-.08em}\text {V} $$3170GeVbased on data collected by the CMS experiment in proton-proton collisions at a centre-of-mass energy of 13$$\,\text {Te}\hspace{-.08em}\text {V}$$TeV, corresponding to an integrated luminosity of 134$$\,\text {fb}^{-1}$$fb-1. The results are compared with predictions from Monte Carlo parton-shower event generator simulations, as well as with fixed-order perturbative quantum chromodynamics (pQCD) predictions at next-to-leading-order (NLO) accuracy obtained with different parton distribution functions (PDFs) and corrected for nonperturbative and electroweak effects. Data and theory agree within uncertainties. From the comparison of the measured observable with the pQCD prediction obtained with the NNPDF3.1 NLO PDFs, the strong coupling at the Z boson mass scale is$$\alpha _\textrm{S} (m_{{\textrm{Z}}}) =0.1177 \pm 0.0013\, \text {(exp)} _{-0.0073}^{+0.0116} \,\text {(theo)} = 0.1177_{-0.0074}^{+0.0117}$$αS(mZ)=0.1177±0.0013(exp)-0.0073+0.0116(theo)=0.1177-0.0074+0.0117, where the total uncertainty is dominated by the scale dependence of the fixed-order predictions. A test of the running of$$\alpha _\textrm{S}$$αSin the$$\,\text {Te}\hspace{-.08em}\text {V}$$TeVregion shows no deviation from the expected NLO pQCD behaviour.

     
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    Free, publicly-accessible full text available August 1, 2025