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Journal articleAaij R, Abdelmotteleb ASW, Beteta CA, et al., 2023,
Measurement of antiproton production from antihyperon decays in pHe collisions at √sNN=110GeV
, European Physical Journal C, Vol: 83, ISSN: 1434-6044The interpretation of cosmic antiproton flux measurements from space-borne experiments is currently limited by the knowledge of the antiproton production cross-section in collisions between primary cosmic rays and the interstellar medium. Using collisions of protons with an energy of 6.5 TeV incident on helium nuclei at rest in the proximity of the interaction region of the LHCb experiment, the ratio of antiprotons originating from antihyperon decays to prompt production is measured for antiproton momenta between 12 and 110GeV\!/c . The dominant antihyperon contribution, namely Λ¯ → p¯ π+ decays from promptly produced Λ¯ particles, is also exclusively measured. The results complement the measurement of prompt antiproton production obtained from the same data sample. At the energy scale of this measurement, the antihyperon contributions to antiproton production are observed to be significantly larger than predictions of commonly used hadronic production models.
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Journal articleAaij R, Abdelmotteleb ASW, Abellan Beteta C, et al., 2023,
Open charm production and asymmetry in pNe collisions at √sNN=68.5GeV
, European Physical Journal C, Vol: 83, ISSN: 1434-6044A measurement of D meson production by the LHCb experiment in its fixed-target configuration is presented. The production of D mesons is studied with a beam of 2.5 TeV protons colliding on a gaseous neon target at rest, corresponding to a nucleon–nucleon centre-of-mass energy of sNN=68.5GeV . The sum of the D and D¯ production cross-section in pNe collisions in the centre-of-mass rapidity range y⋆∈ [- 2.29 , 0] is found to be σD0y⋆∈[-2.29,0]=48.2±0.3±4.5μb/nucleon where the first uncertainty is statistical and the second is systematic. The D- D¯ production asymmetry is also evaluated and suggests a trend towards negative values at large negative y⋆ . The considered models do not account precisely for all the features observed in the LHCb data, but theoretical predictions including 1 % intrinsic charm and 10 % recombination contributions better describe the data than the other models considered.
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Journal articleRossi R, Esposito L, Pesaresi M, et al., 2023,
Track reconstruction and analysis of particle interactions in short bent crystals
, Journal of Instrumentation, Vol: 18Measurements of the interaction of positively charged particles with bent crystals were obtained by developing a new and consolidated analysis method, for the use of UA9 collaboration. The method was deployed to characterize crystals with a length of a few mm along the beam direction and a bending angle in the order of 10 μrad to 100 μrad, typically exploited in the CERN accelerators. To assess their properties and quality, the crystals have been investigated in the Super Proton Synchrotron North Area with a beam of mixed hadrons at 180 GeV. The UA9 telescopic tracker has been used to collect the data. Some of them are used in the present study to describe and validate the applied data-analysis methodology.
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Journal articleTumasyan A, Adam W, Andrejkovic JW, et al., 2023,
Search for long-lived particles decaying to a pair of muons in proton-proton collisions at √s=13 TeV
, JOURNAL OF HIGH ENERGY PHYSICS, ISSN: 1029-8479- Author Web Link
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- Citations: 1
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Journal articleTumasyan A, Adam W, Andrejkovic JW, et al., 2023,
Search for Higgs boson decays to a Z boson and a photon in proton-proton collisions at √s=13 TeV
, JOURNAL OF HIGH ENERGY PHYSICS, ISSN: 1029-8479 -
Journal articleTumasyan A, Adam W, Andrejkovic JW, et al., 2023,
Search for heavy resonances and quantum black holes in eμ, eτ, and μτ final states in proton-proton collisions at √<i>s</i>=13 TeV
, JOURNAL OF HIGH ENERGY PHYSICS, ISSN: 1029-8479 -
Journal articleAbud AA, Abi B, Acciarri R, et al., 2023,
Identification and reconstruction of low-energy electrons in the ProtoDUNE-SP detector
, PHYSICAL REVIEW D, Vol: 107, ISSN: 2470-0010- Author Web Link
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- Citations: 1
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Journal articleShinoki M, Abe K, Hayato Y, et al., 2023,
Measurement of the cosmogenic neutron yield in Super-Kamiokande with gadolinium loaded water
, PHYSICAL REVIEW D, Vol: 107, ISSN: 2470-0010 -
Journal articleAgarwal A, Budd H, Capo J, et al., 2023,
Total neutron cross-section measurement on CH with a novel 3D-projection scintillator detector
, PHYSICS LETTERS B, Vol: 840, ISSN: 0370-2693- Author Web Link
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- Citations: 1
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Journal articleTumasyan A, Adam W, Andrejkovic JW, et al., 2023,
Strange hadron collectivity in pPb and PbPb collisions
, JOURNAL OF HIGH ENERGY PHYSICS, ISSN: 1029-8479 -
Journal articleApple S, Alvarez AD, Kenyon SP, et al., 2023,
Design and performance characterization of a new LISA-like (laser interferometer space antenna-like) gravitational reference sensor and torsion pendulum testbed
, REVIEW OF SCIENTIFIC INSTRUMENTS, Vol: 94, ISSN: 0034-6748- Author Web Link
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- Citations: 2
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Journal articleHall G, Grillo AA, 2023,
ASICs for LHC intermediate tracking detectors
, NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT, Vol: 1050, ISSN: 0168-9002 -
Journal articleAbbiendi G, Alcaraz Maestre J, Álvarez Fernández A, et al., 2023,
The Analytical Method algorithm for trigger primitives generation at the LHC Drift Tubes detector
, Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, Vol: 1049, ISSN: 0168-9002The Compact Muon Solenoid (CMS) experiment prepares its Phase-2 upgrade for the high-luminosity era of the LHC operation (HL-LHC). Due to the increase of occupancy, trigger latency and rates, the full electronics of the CMS Drift Tube (DT) chambers will need to be replaced. In the new design, the time bin for the digitization of the chamber signals will be of around 1 ns, and the totality of the signals will be forwarded asynchronously to the service cavern at full resolution. The new backend system will be in charge of building the trigger primitives of each chamber. These trigger primitives contain the information at chamber level about the muon candidates position, direction, and collision time, and are used as input in the L1 CMS trigger. The added functionalities will improve the robustness of the system against ageing. An algorithm based on analytical solutions for reconstructing the DT trigger primitives, called Analytical Method, has been implemented both as a software C++ emulator and in firmware. Its performance has been estimated using the software emulator with simulated and real data samples, and through hardware implementation tests. Measured efficiencies are 96 to 98% for all qualities and time and spatial resolutions are close to the ultimate performance of the DT chambers. A prototype chain of the HL-LHC electronics using the Analytical Method for trigger primitive generation has been installed during Long Shutdown 2 of the LHC and operated in CMS cosmic data taking campaigns in 2020 and 2021. Results from this validation step, the so-called Slice Test, are presented.
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Journal articleAdam W, Bergauer T, Damanakis K, et al., 2023,
Test beam performance of a CBC3-based mini-module for the Phase-2 CMS Outer Tracker before and after neutron irradiation
, JOURNAL OF INSTRUMENTATION, Vol: 18, ISSN: 1748-0221 -
Journal articleAbud AA, Abi B, Acciarri R, et al., 2023,
Highly-parallelized simulation of a pixelated LArTPC on a GPU
, JOURNAL OF INSTRUMENTATION, Vol: 18, ISSN: 1748-0221 -
Journal articleArmano M, Audley H, Baird J, et al., 2023,
Charging of free-falling test masses in orbit due to cosmic rays: Results from LISA Pathfinder
, Physical Review D, Vol: 107, ISSN: 2470-0010A comprehensive summary of the measurements made to characterize test-mass charging due to the space environment during the LISA Pathfinder mission is presented. Measurements of the residual charge of the test mass after release by the grabbing and positioning mechanism show that the initial charge of the test masses was negative after all releases, leaving the test mass with a potential in the range from -12 to -512. Variations in the neutral test-mass charging rate between 21.7 and 30.7 e s-1 were observed over the course of the 17-month science operations produced by cosmic ray flux changes including a Forbush decrease associated with a small solar energetic particle event. A dependence of the cosmic ray charging rate on the test-mass potential between -30.2 and -40.3 e s-1 V-1 was observed resulting in an equilibrium test-mass potential between 670 and 960 mV, and this is attributed to a contribution to charging from low-energy electrons emitted from the gold surfaces of the gravitational reference sensor. Data from the onboard particle detector show a reliable correlation with the charging rate and with other environmental monitors of the cosmic ray flux. This correlation is exploited to extrapolate test-mass charging rates to a 20-year period giving useful insight into the expected range of charging rate that may be observed in the LISA mission.
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Journal articleTumasyan A, Adam W, Andrejkovic JW, et al., 2023,
Publisher Correction: Observation of triple J/ψ meson production in proton-proton collisions (Nature Physics, (2023), 19, 3, (338-350), 10.1038/s41567-022-01838-y)
, Nature Physics, Vol: 19, ISSN: 1745-2473Correction to: Nature Physics. Published online 19 January 2023. In the version of this article initially published, the first affiliation—Yerevan Physics Institute, Yerevan, Armenia—was missing from the list of author affiliations and has now been inserted in the HTML and PDF versions of the article.
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Journal articleUchida K, Hall G, 2023,
Studies of the CBC3.1 readout ASIC for CMS 2S-modules
, NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT, Vol: 1048, ISSN: 0168-9002 -
Journal articleSirunyan AM, Tumasyan A, Adam W, et al., 2023,
Measurement of prompt and nonprompt charmonium suppression in PbPb collisions at 5.02 TeV (vol 78, 509, 2018)
, EUROPEAN PHYSICAL JOURNAL C, Vol: 83, ISSN: 1434-6044 -
Conference paperQue Z, Loo M, Fan H, et al., 2023,
Optimizing graph Neural Networks for jet tagging in particle physics on FPGAs
, International Conference on Field Programmable Logic and Applications, Publisher: IEEE, Pages: 327-333This work proposes a novel reconfigurable architecture for reducing the latency of JEDI-net, a Graph NeuralNetwork (GNN) based algorithm for jet tagging in particlephysics, which achieves state-of-the-art accuracy. AcceleratingJEDI-net is challenging since it requires low latency to deploythe network for event selection at the CERN Large HadronCollider. This paper proposes an outer-product based matrixmultiplication approach customized for GNN-based JEDI-net,which increases data spatial locality and reduces design latency.It is further enhanced by code transformation with strengthreduction which exploits sparsity patterns and binary adjacencymatrices to increase hardware efficiency while reducing latency.In addition, a customizable template for this architecture hasbeen designed and open-sourced, which enables the generationof low-latency FPGA designs with efficient resource utilizationusing high-level synthesis tools. Evaluation results show that ourFPGA implementation is up to 9.5 times faster and consumes upto 6.5 times less power than a GPU implementation. Moreover,the throughput of our FPGA design is sufficiently high to enabledeployment of JEDI-net in a sub-microsecond, real-time collidertrigger system, enabling it to benefit from improved accuracy.
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Journal articleBertone G, Buchmueller OLL, Cole PSS, 2023,
Perspectives on fundamental cosmology from Low Earth Orbit and the Moon
, NPJ MICROGRAVITY, Vol: 9 -
Journal articleBarbone M, Howard A, Tapper A, et al., 2023,
Demonstration of FPGA acceleration of Monte Carlo simulation
, Journal of Physics : Conference Series, Vol: 2438, Pages: 1-7, ISSN: 1742-6588We present results from a stand-alone simulation of electron single Coulomb scattering as implemented completely on an Field Programmable Gate Array (FPGA) architecture and compared with an identical simulation on a standard CPU. FPGA architectures offer unprecedented speed-up capability for Monte Carlo simulations, however with the caveats of lengthy development cycles and resource limitation, particularly in terms of on-chip memory and DSP blocks. As a proof of principle of acceleration on an FPGA, we chose a single scattering process of electrons in water at an energy of 6 MeV. The initial code-base was implemented in C++ and optimised for CPU processing. To measure the potential performance gains of FPGAs compared to modern multi-core CPUs we computed 100M histories of a 6 MeV electron interacting in water. Without performing any hardware-specific optimisation, the results show that the FPGA implementation is over 110 times faster than an optimised parallel implementation running on 12 CPU-cores, and over 270 times faster than a sequential single-core CPU implementation. The results on both architectures were statistically equivalent. The successful implementation and acceleration results are very encouraging for the future exploitation of more sophisticated Monte Carlo simulation on FPGAs for High Energy Physics applications.
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Journal articleWass PJ, Sumner TJ, Araujo HM, et al., 2023,
Simulating the charging of isolated free-falling masses from TeV to eV energies: Detailed comparison with LISA Pathfinder results
, PHYSICAL REVIEW D, Vol: 107, ISSN: 2470-0010 -
Journal articleTumasyan A, Adam W, Andrejkovic JW, et al., 2023,
Observation of triple J/ψ meson production in proton-proton collisions
, NATURE PHYSICS, ISSN: 1745-2473 -
Journal articleAbe K, Hayato Y, Hiraide K, et al., 2023,
Search for Cosmic-Ray Boosted Sub-GeV Dark Matter Using Recoil Protons at Super-Kamiokande
, PHYSICAL REVIEW LETTERS, Vol: 130, ISSN: 0031-9007- Author Web Link
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- Citations: 1
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Journal articleAalbers J, AbdusSalam SS, Abe K, et al., 2023,
A next-generation liquid xenon observatory for dark matter and neutrino physics
, JOURNAL OF PHYSICS G-NUCLEAR AND PARTICLE PHYSICS, Vol: 50, ISSN: 0954-3899- Author Web Link
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- Citations: 13
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Conference paperFedi G, Fiorendi S, Holmberg M, et al., 2023,
Lessons learnt from the first vertical slice of the CMS Outer Tracker
, Topical Workshop on Electronics for Particle Physics (TWEPP), Publisher: IOP Publishing Ltd, ISSN: 1748-0221 -
Conference paperBrown C, Bundock A, Komm M, et al., 2023,
Neural Network-Based Primary Vertex Reconstruction with FPGAs for the Upgrade of the CMS Level-1 Trigger System
, 20th International Workshop on Advanced Computing and Analysis Techniques in Physics Research (ACAT), Publisher: IOP PUBLISHING LTD, ISSN: 1742-6588 -
Journal articleTumasyan A, Adam W, Andrejkovic JW, et al., 2023,
A search for decays of the Higgs boson to invisible particles in events with a top-antitop quark pair or a vector boson in proton-proton collisions at s=13TeV.
, Eur Phys J C Part Fields, Vol: 83, ISSN: 1434-6044A search for decays to invisible particles of Higgs bosons produced in association with a top-antitop quark pair or a vector boson, which both decay to a fully hadronic final state, has been performed using proton-proton collision data collected at s=13TeV by the CMS experiment at the LHC, corresponding to an integrated luminosity of 138fb-1. The 95% confidence level upper limit set on the branching fraction of the 125GeV Higgs boson to invisible particles, B(H→inv), is 0.54 (0.39 expected), assuming standard model production cross sections. The results of this analysis are combined with previous B(H→inv) searches carried out at s=7, 8, and 13TeV in complementary production modes. The combined upper limit at 95% confidence level on B(H→inv) is 0.15 (0.08 expected).
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Journal articleTumasyan A, Adam W, Andrejkovic JW, et al., 2023,
Measurement of the top quark mass using a profile likelihood approach with the lepton + jets final states in proton-proton collisions at s=13TeV.
, Eur Phys J C Part Fields, Vol: 83, ISSN: 1434-6044The mass of the top quark is measured in 36.3fb-1 of LHC proton-proton collision data collected with the CMS detector at s=13TeV. The measurement uses a sample of top quark pair candidate events containing one isolated electron or muon and at least four jets in the final state. For each event, the mass is reconstructed from a kinematic fit of the decay products to a top quark pair hypothesis. A profile likelihood method is applied using up to four observables per event to extract the top quark mass. The top quark mass is measured to be 171.77±0.37GeV. This approach significantly improves the precision over previous measurements.
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