First measurement of the forward rapidity gap distribution in pPb collisions at ffiffiffiffiffiffiffi p= 8.16 TeV sNN
Physical Review D
Published On 2023/11/20
For the first time at LHC energies, the forward rapidity gap spectra from proton-lead collisions for both proton and lead dissociation processes are presented. The analysis is performed over 10.4 units of pseudorapidity at a center-of-mass energy per nucleon pair of s NN= 8.16 TeV, almost 300 times higher than in previous measurements of diffractive production in proton-nucleus collisions. For lead dissociation processes, which correspond to the pomeron-lead event topology, the epos-lhc generator predictions are a factor of 2 below the data, but the model gives a reasonable description of the rapidity gap spectrum shape. For the pomeron-proton topology, the epos-lhc, qgsjet ii, and hijing predictions are all at least a factor of 5 lower than the data. The latter effect might be explained by a significant contribution of ultraperipheral photoproduction events mimicking the signature of diffractive processes. These data may be of significant help in understanding the high energy limit of quantum chromodynamics and for modeling cosmic ray air showers.
Journal
Physical Review D
Volume
108
Issue
2,301.076
Authors
Francisco Matorras
Universidad de Cantabria
H-Index
320
Research Interests
Particle Physics
Statistical Data Analysis
High Energy physics
Data Science
Physics
University Profile Page
Alberto Ruiz Jimeno (ORCID:0000-0002-3639-0368)
Universidad de Cantabria
H-Index
314
Research Interests
Particle Physics
High Energy Physics
Physics
Doctoral education
Outreach
University Profile Page
Andrei Gritsan
Johns Hopkins University
H-Index
250
Research Interests
Particle Physics
University Profile Page
Adi Bornheim
California Institute of Technology
H-Index
226
Research Interests
Physics
University Profile Page
Isidro González Caballero (ORCID:0000-0002-8087-3199)
Universidad de Oviedo
H-Index
224
Research Interests
High Energy Physics
Scientific computing
Scientific software
University Profile Page
Somnath Choudhury
Indian Institute of Science
H-Index
223
Research Interests
Experimental High Energy Physics
University Profile Page
Luiz Mundim
Universidade do Estado do Rio de Janeiro
H-Index
219
Research Interests
Física
University Profile Page
Sandra dos Santos Padula
Universidade Estadual Paulista
H-Index
217
Research Interests
Física de Altas Energias
University Profile Page
Florencia Canelli
Universität Zürich
H-Index
216
Research Interests
Physics
High Energy Physics
Collider
LHC
University Profile Page
Other Articles from authors
Zoltán Trócsányi
Debreceni Egyetem
arXiv preprint arXiv:2402.14786
Exclusion bounds for neutral gauge bosons
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2024/2/22
Article DetailsIvan D Reid
Brunel University London
The European Physical Journal. C, Particles and Fields
Luminosity determination using Z boson production at the CMS experiment
The measurement of Z boson production is presented as a method to determine the integrated luminosity of CMS data sets. The analysis uses proton–proton collision data, recorded by the CMS experiment at the CERN LHC in 2017 at a center-of-mass energy of 13\(\,\text {Te\hspace {-. 08em} V}\). Events with Z bosons decaying into a pair of muons are selected. The total number of Z bosons produced in a fiducial volume is determined, together with the identification efficiencies and correlations from the same data set, in small intervals of 20 of integrated luminosity, thus facilitating the efficiency and rate measurement as a function of time and instantaneous luminosity. Using the ratio of the efficiency-corrected numbers of Z bosons, the precisely measured integrated luminosity of one data set is used to determine the luminosity of another. For the first time, a full quantitative uncertainty analysis of the use of Z …
2024
Article DetailsAdi Bornheim
California Institute of Technology
Physical Review Letters
Search for Scalar Leptoquarks Produced via τ-Lepton–Quark Scattering in pp Collisions at s= 13 TeV
The first search for scalar leptoquarks produced in τ-lepton–quark collisions is presented. It is based on a set of proton-proton collision data recorded with the CMS detector at the LHC at a center-of-mass energy of 13 TeV corresponding to an integrated luminosity of 138 fb− 1. The reconstructed final state consists of a jet, significant missing transverse momentum, and a τ lepton reconstructed through its hadronic or leptonic decays. Limits are set on the product of the leptoquark production cross section and branching fraction and interpreted as exclusions in the plane of the leptoquark mass and the leptoquark-τ-quark coupling strength.
2024/2/8
Article DetailsFrancisco Matorras
Universidad de Cantabria
arXiv preprint arXiv:2402.05523
Observation of the decay
The first observation of the decay is reported with high significance using proton-proton collision data, corresponding to an integrated luminosity of 9fb, collected with the LHCb detector at centre-of-mass energies of 7, 8, and 13 TeV. The ratio of its branching fraction relative to the channel is measured to be $$ \frac{ {\cal{B}}( B_c^+ \to J/\psi \pi^+\pi^0 ) } { {\cal{B}}( B_c^+ \to J/\psi \pi^+ ) } = 2.80 \pm 0.15 \pm 0.11 \pm 0.16 \,, $$ where the first uncertainty is statistical, the second systematic and the third related to imprecise knowledge of the branching fractions for and decays, which are used to determine the detection efficiency. The mass spectrum is found to be consistent with the dominance of an intermediate contribution in accordance with a model based on QCD factorisation.
2024/2/8
Article DetailsLuiz Mundim
Universidade do Estado do Rio de Janeiro
Search for exotic decays of the Higgs boson to a pair of pseudoscalars in the and final states
A search for exotic decays of the Higgs boson (H) with a mass of 125 GeV to a pair of light pseudoscalars is performed in final states where one pseudoscalar decays to two b quarks and the other to a pair of muons or leptons. A data sample of proton-proton collisions at = 13 TeV corresponding to an integrated luminosity of 138 fb recorded with the CMS detector is analyzed. No statistically significant excess is observed over the standard model backgrounds. Upper limits are set at 95% confidence level (CL) on the Higgs boson branching fraction to bb and to bb, via a pair of s. The limits depend on the pseudoscalar mass and are observed to be in the range (0.17-3.3) 10 and (1.7-7.7) 10 in the bb and bb final states, respectively. In the framework of models with two Higgs doublets and a complex scalar singlet (2HDM+S), the results of the two final states are combined to determine model-independent upper limits on the branching fraction (H bb) at 95% CL, with being a muon or a lepton. For different types of 2HDM+S, upper bounds on the branching fraction (H ) are extracted from the combination of the two channels. In most of the Type II 2HDM+S parameter space, H ) values above 0.23 are excluded at 95% CL for values between 15 and 60 GeV.
2024/2/20
Article DetailsFreya Blekman
Vrije Universiteit Brussel
arXiv preprint arXiv:2403.15518
Performance of the CMS electromagnetic calorimeter in pp collisions at = 13 TeV
The operation and performance of the Compact Muon Solenoid (CMS) electromagnetic calorimeter (ECAL) are presented, based on data collected in pp collisions at = 13 TeV at the CERN LHC, in the years from 2015 to 2018 (LHC Run 2), corresponding to an integrated luminosity of 151 fb. The CMS ECAL is a scintillating lead-tungstate crystal calorimeter, with a silicon strip preshower detector in the forward region that provides precise measurements of the energy and the time-of-arrival of electrons and photons. The successful operation of the ECAL is crucial for a broad range of physics goals, ranging from observing the Higgs boson and measuring its properties, to other standard model measurements and searches for new phenomena. Precise calibration, alignment, and monitoring of the ECAL response are important ingredients to achieve these goals. To face the challenges posed by the higher luminosity, which characterized the operation of the LHC in Run 2, the procedures established during the 2011-2012 run of the LHC have been revisited and new methods have been developed for the energy measurement and for the ECAL calibration. The energy resolution of the calorimeter, for electrons from Z boson decays reaching the ECAL without significant loss of energy by bremsstrahlung, was better than 1.8%, 3.0%, and 4.5% in the $\lvert\eta\rvert$ intervals [0.0,0.8], [0.8,1.5], [1.5, 2.5], respectively. This resulting performance is similar to that achieved during Run 1 in 2011-2012, in spite of the more severe running conditions.
2024/4/2
Article DetailsLuiz Mundim
Universidade do Estado do Rio de Janeiro
A search for bottom-type vector-like quark pair production in dileptonic and fully hadronic final states in proton-proton collisions at = 13 TeV
A search is described for the production of a pair of bottom-type vector-like quarks (B VLQs) with mass greater than 1000 GeV. Each B VLQ decays into a b quark and a Higgs boson, a b quark and a Z boson, or a t quark and a W boson. This analysis considers both fully hadronic final states and those containing a charged lepton pair from a Z boson decay. The products of the H bb boson decay and of the hadronic Z or W 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 138 fb collected in proton-proton collisions at = 13 TeV 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 B VLQ mass at 95% confidence level. These depend on the B VLQ branching fractions and are 1570 and 1540 GeV for 100% B bH and 100% B bZ, respectively. In most cases, the mass limits obtained exceed previous limits by at least 100 GeV.
2024/2/27
Article DetailsJody K Wilson
University of New Hampshire
Physical Review C
Two-particle Bose-Einstein correlations and their Lévy parameters in PbPb collisions at TeV
Two-particle Bose–Einstein momentum correlation functions are studied for charged-hadron pairs in lead-lead collisions at a center-of-mass energy per nucleon pair of s NN= 5.02 TeV. The data sample, containing 4.27× 10 9 minimum bias events corresponding to an integrated luminosity of 0.607 nb− 1, was collected by the CMS experiment in 2018. The experimental results are discussed in terms of a Lévy-type source distribution. The parameters of this distribution are extracted as functions of particle pair average transverse mass and collision centrality. These parameters include the Lévy index or shape parameter α, the Lévy scale parameter R, and the correlation strength parameter λ. The source shape, characterized by α, is found to be neither Cauchy nor Gaussian, implying the need for a full Lévy analysis. Similarly to what was previously found for systems characterized by Gaussian source radii, a …
2024/2/23
Article DetailsSandra dos Santos Padula
Universidade Estadual Paulista
Journal of High Energy Physics
Measurement of the τ lepton polarization in Z boson decays in proton-proton collisions at = 13 TeV
The polarization of τ leptons is measured using leptonic and hadronic τ lepton decays in Z→ τ+ τ− events in proton-proton collisions at= 13 TeV recorded by CMS at the CERN LHC with an integrated luminosity of 36.3 fb− 1. The measured τ− lepton polarization at the Z boson mass pole is=− 0.144±0.006 (stat)±0.014 (syst)=− 0.144±0.015, in good agreement with the measurement of the τ lepton asymmetry parameter of A τ= 0.1439±0.0043= at LEP. The τ lepton polarization depends on the ratio of the vector to axial-vector couplings of the τ leptons in the neutral current expression, and thus on the effective weak mixing angle sin 2, independently of the Z boson production mechanism. The obtained value sin 2= 0.2319±0. 0008 (stat)±0. 0018 (syst)= 0. 2319±0. 0019 is in good agreement with measurements at e+ e− colliders.
2024/1
Article DetailsLuiz Mundim
Universidade do Estado do Rio de Janeiro
DRD1 Extended R&D; Proposal
This document realized in the framework of the newly established Gaseous Detector R&D Collaboration (DRD1), presents a comprehensive overview of the current state-of-the-art and the challenges related to various gaseous detector concepts and technologies. It is divided into two key sections. The first section, titled" Executive summary", offers a broad perspective on the collaborative scientific organization, characterized by the presence of eight Working Groups (WGs), which serve as the cornerstone for our forthcoming scientific endeavours. This section also contains a detailed inventory of R&D tasks structured into distinct Work Packages (WPs), in alignment with strategic R&D programs that funding agencies may consider supporting. Furthermore, it underlines the critical infrastructures and tools essential for advancing us towards our technological objectives, as outlined in the ECFA R&D roadmap. The second section, titled" Scientific Proposal and R&D Framework," delves deeply into the research work and plans. Each chapter in this section provides a detailed exploration of the activities planned by the WGs, underscoring their pivotal role in shaping our future scientific pursuits. This DRD1 proposal reinforces our unwavering commitment to a collaborative research program that will span the next three years.
2024/1/9
Article DetailsHamed Bakhshiansohi
Isfahan University of Technology
The European physical journal. C, Particles and fields
Measurement of the production cross section for a W boson in association with a charm quark in proton–proton collisions at [... formula...]
The strange quark content of the proton is probed through the measurement of the production cross section for a W boson and a charm (c) quark in proton–proton collisions at a center-of-mass energy of 13 Te V. The analysis uses a data sample corresponding to a total integrated luminosity of 138 fb-1 collected with the CMS detector at the LHC. The W bosons are identified through their leptonic decays to an electron or a muon, and a neutrino. Charm jets are tagged using the presence of a muon or a secondary vertex inside the jet. The W+ c production cross section and the cross section ratio R c±= σ (W++ c)/σ (W-+ c) are measured inclusively and differentially as functions of the transverse momentum and the pseudorapidity of the lepton originating from the W boson decay. The precision of the measurements is improved with respect to previous studies, reaching 1% in R c±= 0.950±0.005 (stat)±0.010 (syst). The …
2024
Article DetailsGiovanni Organtini
Sapienza Università di Roma
Portable acceleration of CMS computing workflows with coprocessors as a service
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.
2024/2/27
Article DetailsFreya Blekman
Vrije Universiteit Brussel
arXiv preprint arXiv:2403.00100
Search for heavy neutral leptons in final states with electrons, muons, and hadronically decaying tau leptons in proton-proton collisions at 13 TeV
A search for heavy neutral leptons (HNLs) of Majorana or Dirac type using protonproton collision data at√ s= 13 TeV is presented. The data were collected by the CMS experiment at the CERN LHC and correspond to an integrated luminosity of 138 fb− 1. Events with three charged leptons (electrons, muons, and hadronically decaying tau leptons) are selected, corresponding to HNL production in association with a charged lepton and decay of the HNL to two charged leptons and a standard model (SM) neutrino. The search is performed for HNL masses between 10 GeV and 1.5 TeV. No evidence for an HNL signal is observed in data. Upper limits at 95% confidence level are found for the squared coupling strength of the HNL to SM neutrinos, considering exclusive coupling of the HNL to a single SM neutrino generation, for both Majorana and Dirac HNLs. The limits exceed previously achieved experimental constraints for a wide range of HNL masses, and the limits on tau neutrino coupling scenarios with HNL masses above the W boson mass are presented for the first time.
2024/3/1
Article DetailsChang-Seong Moon
Kyungpook National University
Journal of High Energy Physics
Measurement of the τ lepton polarization in Z boson decays in proton-proton collisions at = 13 TeV
The polarization of τ leptons is measured using leptonic and hadronic τ lepton decays in Z→ τ+ τ− events in proton-proton collisions at= 13 TeV recorded by CMS at the CERN LHC with an integrated luminosity of 36.3 fb− 1. The measured τ− lepton polarization at the Z boson mass pole is=− 0.144±0.006 (stat)±0.014 (syst)=− 0.144±0.015, in good agreement with the measurement of the τ lepton asymmetry parameter of A τ= 0.1439±0.0043= at LEP. The τ lepton polarization depends on the ratio of the vector to axial-vector couplings of the τ leptons in the neutral current expression, and thus on the effective weak mixing angle sin 2, independently of the Z boson production mechanism. The obtained value sin 2= 0.2319±0. 0008 (stat)±0. 0018 (syst)= 0. 2319±0. 0019 is in good agreement with measurements at e+ e− colliders.
2024/1
Article DetailsPanos Razis
University of Cyprus
Portable acceleration of CMS computing workflows with coprocessors as a service
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.
2024/2/27
Article DetailsLuiz Mundim
Universidade do Estado do Rio de Janeiro
arXiv preprint arXiv:2403.00100
Search for heavy neutral leptons in final states with electrons, muons, and hadronically decaying tau leptons in proton-proton collisions at 13 TeV
A search for heavy neutral leptons (HNLs) of Majorana or Dirac type using protonproton collision data at√ s= 13 TeV is presented. The data were collected by the CMS experiment at the CERN LHC and correspond to an integrated luminosity of 138 fb− 1. Events with three charged leptons (electrons, muons, and hadronically decaying tau leptons) are selected, corresponding to HNL production in association with a charged lepton and decay of the HNL to two charged leptons and a standard model (SM) neutrino. The search is performed for HNL masses between 10 GeV and 1.5 TeV. No evidence for an HNL signal is observed in data. Upper limits at 95% confidence level are found for the squared coupling strength of the HNL to SM neutrinos, considering exclusive coupling of the HNL to a single SM neutrino generation, for both Majorana and Dirac HNLs. The limits exceed previously achieved experimental constraints for a wide range of HNL masses, and the limits on tau neutrino coupling scenarios with HNL masses above the W boson mass are presented for the first time.
2024/3/1
Article DetailsFabio Ferri
Università degli Studi dell'Insubria
Physics Letters B
Search for new Higgs bosons via same-sign top quark pair production in association with a jet in proton-proton collisions at s= 13TeV
A search is presented for new Higgs bosons in proton-proton (pp) collision events in which a same-sign top quark pair is produced in association with a jet, via the pp→ tH∕ A→ ttc and pp→ tH∕ A→ ttu processes. Here, H and A represent the extra scalar and pseudoscalar boson, respectively, of the second Higgs doublet in the generalized two-Higgs-doublet model (g2HDM). The search is based on pp collision data collected at a center-of-mass energy of 13 TeV with the CMS detector at the LHC, corresponding to an integrated luminosity of 138 fb− 1. Final states with a same-sign lepton pair in association with jets and missing transverse momentum are considered. New Higgs bosons in the 200–1000GeV mass range and new Yukawa couplings between 0.1 and 1.0 are targeted in the search, for scenarios in which either H or A appear alone, or in which they coexist and interfere. No significant excess above the standard model prediction is observed. Exclusion limits are derived in the context of the g2HDM.
2024/2/2
Article DetailsGiovanni Organtini
Sapienza Università di Roma
Enriching the physics program of the CMS experiment via data scouting and data parking
Specialized data-taking and data-processing techniques were introduced by the CMS experiment in Run 1 of the CERN LHC to enhance the sensitivity of searches for new physics and the precision of standard model measurements. These techniques, termed data scouting and data parking, extend the data-taking capabilities of CMS beyond the original design specifications. The novel data-scouting strategy trades complete event information for higher event rates, while keeping the data bandwidth within limits. Data parking involves storing a large amount of raw detector data collected by algorithms with low trigger thresholds to be processed when sufficient computational power is available to handle such data. The research program of the CMS Collaboration is greatly expanded with these techniques. The implementation, performance, and physics results obtained with data scouting and data parking in CMS over the last decade are discussed in this Report, along with new developments aimed at further improving low-mass physics sensitivity over the next years of data taking.
2024/4/2
Article DetailsIvan D Reid
Brunel University London
Physical Review Letters
Search for Inelastic Dark Matter in Events with Two Displaced Muons and Missing Transverse Momentum in Proton-Proton Collisions at s= 13 TeV
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2024/1/23
Article DetailsPascal Vanlaer
Université Libre de Bruxelles
Portable acceleration of CMS computing workflows with coprocessors as a service
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2024/2/27
Article DetailsOther articles from Physical Review D journal
Laurent Lellouch
Aix-Marseille Université
Physical Review D
Hadronic vacuum polarization: comparing lattice QCD and data-driven results in systematically improvable ways
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2024/4/22
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University of Wisconsin-Madison
Physical Review D
Search for quantum black hole production in lepton+ jet final states using proton-proton collisions at s= 13 TeV with the ATLAS detector
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2024/2/27
Article DetailsChristian Weber
Technische Universität Berlin
Physical Review D
Search for quantum black hole production in lepton+ jet final states using proton-proton collisions at s= 13 TeV with the ATLAS detector
A search for quantum black holes in electron+ jet and muon+ jet invariant mass spectra is performed with 140 fb− 1 of data collected by the ATLAS detector in proton-proton collisions at s= 13 TeV at the Large Hadron Collider. The observed invariant mass spectrum of lepton+ jet pairs is consistent with Standard Model expectations. Upper limits are set at 95% confidence level on the production cross section times branching fractions for quantum black holes decaying into a lepton and a quark in a search region with invariant mass above 2.0 TeV. The resulting quantum black hole lower mass threshold limit is 9.2 TeV in the Arkani-Hamed-Dimopoulos-Dvali model, and 6.8 TeV in the Randall-Sundrum model.
2024/2/27
Article DetailsDariescu
Universitatea Alexandru Ioan Cuza din Iasi
Physical Review D
Charged particles in the background of the Kiselev solution in power-Maxwell electrodynamics
In this work we analyze the motion of charged particles in the background of the Kiselev geometry, which is considered here as an exact solution in the context of power-Maxwell electrodynamics. As it is well known, one can use either an electric ansatz or a magnetic one for the nonlinear electromagnetic field. We study the motion of an electrically charged particle for an electrically charged black hole and also for a magnetically charged black hole. In the second case the motion is restricted to Poincaré cones of various angles, as expected.
2024/1/17
Article DetailsHiranya Peiris
University College London
Physical Review D
Analog vacuum decay from vacuum initial conditions
Ultracold atomic gases can undergo phase transitions that mimic relativistic vacuum decay, allowing us to empirically test early Universe physics in tabletop experiments. We investigate the physics of these analog systems, going beyond previous analyses of the classical equations of motion to study quantum fluctuations in the cold-atom false vacuum. We show that the fluctuation spectrum of this vacuum state agrees with the usual relativistic result in the regime where the classical analogy holds, providing further evidence for the suitability of these systems for studying vacuum decay. Using a suite of semiclassical lattice simulations, we simulate bubble nucleation from this analog vacuum state in a 1D homonuclear potassium-41 mixture, finding qualitative agreement with instanton predictions. We identify realistic parameters for this system that will allow us to study vacuum decay with current experimental …
2024/1/4
Article DetailsHiranya Peiris
University College London
Physical Review D
Deep learning insights into cosmological structure formation
The evolution of linear initial conditions present in the early Universe into extended halos of dark matter at late times can be computed using cosmological simulations. However, a theoretical understanding of this complex process remains elusive; in particular, the role of anisotropic information in the initial conditions in establishing the final mass of dark matter halos remains a long-standing puzzle. Here, we build a deep learning framework to investigate this question. We train a three-dimensional convolutional neural network to predict the mass of dark matter halos from the initial conditions, and quantify in full generality the amounts of information in the isotropic and anisotropic aspects of the initial density field about final halo masses. We find that anisotropies add a small, albeit statistically significant amount of information over that contained within spherical averages of the density field about final halo mass …
2024/3/14
Article DetailsCharalampos Moustakidis
Aristotle University of Thessaloniki
Physical Review D
Constraints for the X17 boson from compact objects observations
We investigate the hypothetical X17 boson on neutron stars and quark stars (QSs) using various hadronic equation of states (EoSs) with phenomenological or microscopic origin. Our aim is to set realistic constraints on its coupling constant and the mass scaling, with respect to causality and various possible upper mass limits and the dimensionless tidal deformability Λ 1.4. In particular, we pay special attention to two main phenomenological parameters of the X17, one is related to the coupling constant g that it has with hadrons or quarks and the other with the in-medium effects through regulator C. Both are very crucial concerning the contribution on the total energy density and pressure. In the case of considering the X17 as a carrier of nuclear force in relativistic mean field theory, an admixture into the vector boson segment was constrained by 20% and 30%. In our investigation, we came to the general conclusion …
2024/2/15
Article DetailsCharalampos Moustakidis
Aristotle University of Thessaloniki
Physical Review D
Hybrid stars in light of the HESS J1731-347 remnant and the PREX-II experiment
The recent analysis on the central compact object in the HESS J1731-347 remnant suggests interestingly small values for its mass and radius. Such an observation favors soft nuclear models that may be challenged by the observation of massive compact stars. In contrast, the recent PREX-II experiment, concerning the neutron skin thickness of Pb 208, points toward stiff equations of state that favor larger compact star radii. In the present study, we aim to explore the compatibility between stiff hadronic equations of state (favored by PREX-II) and the HESS J1731-347 remnant in the context of hybrid stars. For the construction of hybrid equations of state we use three widely employed Skyrme models combined with the well-known vector MIT bag model. Furthermore we consider two different scenarios concerning the energy density of the bag. In the first case, that of a constant bag parameter, we find that the resulting …
2024/3/14
Article DetailsClaudia Moreno
Universidad de Guadalajara
Physical Review D
GWTC-2.1: Deep extended catalog of compact binary coalescences observed by LIGO and Virgo during the first half of the third observing run
The second Gravitational-Wave Transient Catalog, GWTC-2, reported on 39 compact binary coalescences observed by the Advanced LIGO and Advanced Virgo detectors between 1 April 2019 15∶ 00 UTC and 1 October 2019 15∶ 00 UTC. Here, we present GWTC-2.1, which reports on a deeper list of candidate events observed over the same period. We analyze the final version of the strain data over this period with improved calibration and better subtraction of excess noise, which has been publicly released. We employ three matched-filter search pipelines for candidate identification, and estimate the probability of astrophysical origin for each candidate event. While GWTC-2 used a false alarm rate threshold of 2 per year, we include in GWTC-2.1, 1201 candidates that pass a false alarm rate threshold of 2 per day. We calculate the source properties of a subset of 44 high-significance candidates that have a …
2024/1/5
Article DetailsClaudia Moreno
Universidad de Guadalajara
Physical Review D
Post-Newtonian gravitational waves with cosmological constant from the Einstein-Hilbert theory
We study the compact binary dynamics in the post-Newtonian approach implemented to the Einstein-Hilbert action adding the cosmological constant Λ at first post-Newtonian (1PN) order. We consider very small values of Λ finding that it plays the role of a PN factor to derive the Lagrangian of a compact two-body system at the center of mass frame at 1PN. Furthermore, the phase function ϕ (t) is obtained from the balance equation, and the two polarizations h+ and h× are also calculated. We observe changes due to Λ only at very low frequencies, and we notice that it plays the role of “stretch” the spacetime such that both amplitudes become smaller. However, given its nearly negligible value, Λ has no relevance at higher frequencies whatsoever.
2024/3/19
Article DetailsIan M. Shoemaker
University of South Dakota
Physical Review D
Long-lived particles and the quiet Sun
The nuclear reaction network within the interior of the Sun is an efficient MeV physics factory and can produce long-lived particles generic to dark sector models. In this work we consider the sensitivity of satellite instruments, primarily the RHESSI spectrometer, that observe the quiet Sun in the MeV regime where backgrounds are low. We find that quiet Sun observations offer a powerful and complementary probe in regions of parameter space, where the long-lived particle decay length is longer than the radius of the Sun and shorter than the distance between the Sun and Earth. We comment on connections to recent model-building work on heavy neutral leptons coupled to neutrinos and high-quality axions from mirror symmetries.
2024/1/22
Article DetailsHao Y. Zhang / 张昊
University of Pennsylvania
Physical Review D
Intermediate defect groups, polarization pairs, and noninvertible duality defects
Within the framework of relative and absolute quantum field theories (QFTs), we present a general formalism for understanding polarizations of the intermediate defect group and constructing noninvertible duality defects in theories in 2 k spacetime dimensions with self-dual gauge fields. We introduce the polarization pair, which fully specifies absolute QFTs as far as their (k− 1)-form defect groups are concerned, including their (k− 1)-form symmetries, global structures (including discrete θ-angle), and local counterterms. Using the associated symmetry topological field theory (TFT), we show that the polarization pair is capable of succinctly describing topological manipulations, eg, gauging (k− 1)-form global symmetries and stacking counterterms, of absolute QFTs. Furthermore, automorphisms of the (k− 1)-form charge lattice naturally act on polarization pairs via their action on the defect group; they can be viewed as …
2024/1/10
Article DetailsIgor Altsybeev
St. Petersburg State University
Physical Review D
Measurement of the fraction of jet longitudinal momentum carried by baryons in collisions
Recent measurements of charm-baryon production in hadronic collisions have questioned the universality of charm-quark fragmentation across different collision systems. In this work the fragmentation of charm quarks into charm baryons is probed, by presenting the first measurement of the longitudinal jet momentum fraction carried by Λ c+ baryons, z∥ ch, in hadronic collisions. The results are obtained in proton-proton (p p) collisions at s= 13 TeV at the LHC, with Λ c+ baryons and charged (track-based) jets reconstructed in the transverse momentum intervals of 3≤ p T Λ c+< 15 GeV/c and 7≤ p T jet ch< 15 GeV/c, respectively. The z∥ ch distribution is compared to a measurement of D 0-tagged charged jets in p p collisions as well as to pythia 8 simulations. The data hints that the fragmentation of charm quarks into charm baryons is softer with respect to charm mesons, in the measured kinematic interval, as …
2024/4/5
Article DetailsFabrizio BARONE
Università degli Studi di Salerno
Physical Review D
GWTC-2.1: Deep extended catalog of compact binary coalescences observed by LIGO and Virgo during the first half of the third observing run
The second Gravitational-Wave Transient Catalog, GWTC-2, reported on 39 compact binary coalescences observed by the Advanced LIGO and Advanced Virgo detectors between 1 April 2019 15∶ 00 UTC and 1 October 2019 15∶ 00 UTC. Here, we present GWTC-2.1, which reports on a deeper list of candidate events observed over the same period. We analyze the final version of the strain data over this period with improved calibration and better subtraction of excess noise, which has been publicly released. We employ three matched-filter search pipelines for candidate identification, and estimate the probability of astrophysical origin for each candidate event. While GWTC-2 used a false alarm rate threshold of 2 per year, we include in GWTC-2.1, 1201 candidates that pass a false alarm rate threshold of 2 per day. We calculate the source properties of a subset of 44 high-significance candidates that have a …
2024/1/5
Article DetailsJohn Veitch
University of Glasgow
Physical Review D
GWTC-2.1: Deep extended catalog of compact binary coalescences observed by LIGO and Virgo during the first half of the third observing run
The second Gravitational-Wave Transient Catalog, GWTC-2, reported on 39 compact binary coalescences observed by the Advanced LIGO and Advanced Virgo detectors between 1 April 2019 15∶ 00 UTC and 1 October 2019 15∶ 00 UTC. Here, we present GWTC-2.1, which reports on a deeper list of candidate events observed over the same period. We analyze the final version of the strain data over this period with improved calibration and better subtraction of excess noise, which has been publicly released. We employ three matched-filter search pipelines for candidate identification, and estimate the probability of astrophysical origin for each candidate event. While GWTC-2 used a false alarm rate threshold of 2 per year, we include in GWTC-2.1, 1201 candidates that pass a false alarm rate threshold of 2 per day. We calculate the source properties of a subset of 44 high-significance candidates that have a …
2024/1/5
Article DetailsElham E Khoda
University of Washington
Physical Review D
Search for quantum black hole production in lepton+ jet final states using proton-proton collisions at s= 13 TeV with the ATLAS detector
A search for quantum black holes in electron+ jet and muon+ jet invariant mass spectra is performed with 140 fb− 1 of data collected by the ATLAS detector in proton-proton collisions at s= 13 TeV at the Large Hadron Collider. The observed invariant mass spectrum of lepton+ jet pairs is consistent with Standard Model expectations. Upper limits are set at 95% confidence level on the production cross section times branching fractions for quantum black holes decaying into a lepton and a quark in a search region with invariant mass above 2.0 TeV. The resulting quantum black hole lower mass threshold limit is 9.2 TeV in the Arkani-Hamed-Dimopoulos-Dvali model, and 6.8 TeV in the Randall-Sundrum model.
2024/2/27
Article DetailsDavid Silvermyr
Lunds Universitet
Physical Review D
Measurement of the fraction of jet longitudinal momentum carried by baryons in collisions
Recent measurements of charm-baryon production in hadronic collisions have questioned the universality of charm-quark fragmentation across different collision systems. In this work the fragmentation of charm quarks into charm baryons is probed, by presenting the first measurement of the longitudinal jet momentum fraction carried by Λ c+ baryons, z∥ ch, in hadronic collisions. The results are obtained in proton-proton (p p) collisions at s= 13 TeV at the LHC, with Λ c+ baryons and charged (track-based) jets reconstructed in the transverse momentum intervals of 3≤ p T Λ c+< 15 GeV/c and 7≤ p T jet ch< 15 GeV/c, respectively. The z∥ ch distribution is compared to a measurement of D 0-tagged charged jets in p p collisions as well as to pythia 8 simulations. The data hints that the fragmentation of charm quarks into charm baryons is softer with respect to charm mesons, in the measured kinematic interval, as …
2024/4/5
Article DetailsGiuseppe Callea
University of Glasgow
Physical Review D
Search for quantum black hole production in lepton+ jet final states using proton-proton collisions at s= 13 TeV with the ATLAS detector
A search for quantum black holes in electron+ jet and muon+ jet invariant mass spectra is performed with 140 fb− 1 of data collected by the ATLAS detector in proton-proton collisions at s= 13 TeV at the Large Hadron Collider. The observed invariant mass spectrum of lepton+ jet pairs is consistent with Standard Model expectations. Upper limits are set at 95% confidence level on the production cross section times branching fractions for quantum black holes decaying into a lepton and a quark in a search region with invariant mass above 2.0 TeV. The resulting quantum black hole lower mass threshold limit is 9.2 TeV in the Arkani-Hamed-Dimopoulos-Dvali model, and 6.8 TeV in the Randall-Sundrum model.
2024/2/27
Article DetailsMinsu Park
University of Pennsylvania
Physical Review D
Atacama Cosmology Telescope: The persistence of neutrino self-interaction in cosmological measurements
We use data from the Atacama Cosmology Telescope (ACT) DR4 to search for the presence of neutrino self-interaction in the cosmic microwave background. Consistent with prior works, the posterior distributions we find are bimodal, with one mode consistent with Λ CDM and one where neutrinos strongly self-interact. By combining ACT data with large-scale information from WMAP, we find that a delayed onset of neutrino free streaming caused by significantly strong neutrino self-interaction is compatible with these data at the 2− 3 σ level. As seen in the past, the preference shifts to Λ CDM with the inclusion of Planck data. We determine that the preference for strong neutrino self-interaction is largely driven by angular scales corresponding to 700≲ ℓ≲ 1000 in the ACT E-mode polarization data. This region is expected to be key to discriminate between neutrino self-interacting modes and will soon be probed with …
2024/2/1
Article DetailsHerodotos Herodotou
Cyprus University of Technology
Physical Review D
Supersymmetric QCD on the lattice: Fine-tuning of the Yukawa couplings
We determine the fine-tuning of the Yukawa couplings of supersymmetric QCD, discretized on a lattice. We use perturbation theory at one-loop level. The modified minimal subtraction scheme (MS) is employed; by its definition, this scheme requires perturbative calculations, in the continuum and/or on the lattice. On the lattice, we utilize the Wilson formulation for gluon, quark, and gluino fields; for squark fields we use naive discretization. The sheer difficulties of this study lie in the fact that different components of squark fields mix among themselves at the quantum level and the action’s symmetries, such as parity and charge conjugation, allow an additional Yukawa coupling. Consequently, for an appropriate fine-tuning of the Yukawa terms, these mixings must be taken into account in the renormalization conditions. All Green’s functions and renormalization factors are analytic expressions depending on the number of …
2024/2/20
Article Details