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Publications related to LHC (10,000)
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Preprint
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The 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 digitisation of the chamber signals...
Article
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We present a new calculation of axionlike particle (ALP) production in the semiexclusive photon-initiated (PI) channel, that is either with intact outgoing protons or rapidity gaps present in the final state, and with no color flow between the colliding LHC protons. This is the first full treatment of this process, accounting for both the possibili...
Preprint
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The quest to understand the fundamental building blocks of nature and their interactions is one of the oldest and most ambitious of human scientific endeavors. CERN's Large Hadron Collider (LHC) represents a huge step forward in this quest. The discovery of the Higgs boson, the observation of exceedingly rare decays of $B$ mesons, and stringent con...
Preprint
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A Large Ion Collider Experiment (ALICE) has been conceived and constructed as a heavy-ion experiment at the LHC. During LHC Runs 1 and 2, it has produced a wide range of physics results using all collision systems available at the LHC. In order to best exploit new physics opportunities opening up with the upgraded LHC and new detector technologies,...
Article
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Jets of hadrons produced at high-energy colliders provide experimental access to the dynamics of asymptotically free quarks and gluons and their confinement into hadrons. In this Letter, we show that the high energies of the Large Hadron Collider (LHC), together with the exceptional resolution of its detectors, allow multipoint correlation function...
Article
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The first step of photosynthesis in plants is performed by the light-harvesting complexes (LHC), a large family of pigment-binding proteins embedded in the photosynthetic membranes. These complexes are conserved across species, suggesting that each has a distinct role. However, they display a high degree of sequence homology and their static struct...
Article
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A bstract We study the LHC discovery potential in the search for heavy neutral leptons (HNL) with a new signature: a displaced shower in the CMS muon detector, giving rise to a large cluster of hits forming a displaced shower. A new Delphes module is used to model the CMS detector response for such displaced decays. We reinterpret a dedicated CMS s...
Preprint
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In these proceedings, two multi-differential analyses performed in pp collisions collected by the ALICE collaboration during the LHC Run 2 are presented. One investigates the dependence of strange particle production with multiplicity and effective energy, whereas the other clarifies how strangeness enhancement is correlated to the leading jet in t...
Article
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We discuss production of far-forward charm and anticharm quarks, D mesons and antimesons, and neutrinos and antineutrinos from their semileptonic decays in proton-proton collisions at the LHC energies. We include the gluon-gluon fusion gg→cc¯, the intrinsic charm (IC) gc→gc as well as the recombination gq→Dc partonic mechanisms. The calculations ar...
Preprint
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Measurements of differential cross sections are presented for inclusive isolated-photon production in $pp$ collisions at a centre-of-mass energy of 13 TeV provided by the LHC and using 139 fb$^{-1}$ of data recorded by the ATLAS experiment. The cross sections are measured as functions of the photon transverse energy in different regions of photon p...
Article
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A bstract Many compelling beyond the Standard Model scenarios predict signals that result in unconventional charged particle trajectories. Signatures for which unusual tracks are the most conspicuous feature of the event pose significant challenges for experiments at the Large Hadron Collider (LHC), particularly for the trigger. This article presen...
Preprint
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ALICE is one of the four experiments at the CERN Large Hadron Collider (LHC) specifically designed to study nuclear matter at extreme conditions of temperature and pressure. The LHC Run 3 started officially in July 2022 with proton-proton (pp) collisions at a centre-of-mass energy $\sqrt{s}$ = 13.6 TeV after a shutdown of more than two years to all...
Article
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The diffusion wake accompanying the jet-induced Mach cone provides a unique probe of the properties of quark-gluon plasma in high-energy heavy-ion collisions. It can be characterized by a depletion of soft hadrons in the opposite direction of the propagating jet. We explore the 3D structure of the diffusion wake induced by γ-triggered jets in Pb+Pb...
Preprint
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The ALICE Experiment has replaced its Inner Tracking System with a 7-layer pixel-only tracker made out of more than 24000 monolithic active pixel sensor chips, in order to fulfill the requirements of the physics program of the LHC Run 3. The upgraded Inner Tracking System (ITS2) has been installed in the ALICE experiment during the LHC long shutdow...
Preprint
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A search for long-lived particles decaying into hadrons is presented. The analysis uses 139 fb$^{-1}$ of $pp$ collision data collected at $\sqrt{s} = 13$ TeV by the ATLAS detector at the LHC using events that contain multiple energetic jets and a displaced vertex. The search employs dedicated reconstruction techniques that significantly increase th...
Article
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The scotogenic model generates Majorana neutrino masses radiatively, with dark matter particles running in the loop. We explore the parameter space in which the relic density of fermionic dark matter is generated via a conversion-driven freeze-out mechanism. The necessity for small Yukawa couplings to initiate chemical decoupling for conversion pro...
Preprint
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In this article we combine the recently proposed method for factorisation-aware matrix element surrogates arXiv:2107.06625 with the unbiased unweighting algorithm of arXiv:2109.11964. We show that employing a sophisticated neural network emulation of QCD multijet matrix elements based on Catani-Seymour dipole factorisation can lead to a drastic acc...
Preprint
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The next upgrade of the Large Hadron Collider (LHC) is planned from 2026 when the collider will move to its High Luminosity phase (HL-LHC). The CMS detector needs to be substantially upgraded during this period to exploit the fourfold increase in luminosity provided by the HL-LHC. This upgrade is referred to as the CMS Phase-2 Upgrade. A program of...
Preprint
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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 $\Lambda_{\rm c}...
Preprint
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The strategies for and the performance of the CMS tracker alignment during the 2021-2022 LHC commissioning preceding the Run 3 data-taking period are described. The results of the very first tracker alignment after the pixel reinstallation, performed with cosmic ray muons recorded with the solenoid magnet off are presented. Also, the performance of...
Preprint
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The inner tracking system of the CMS experiment, which comprises Silicon Pixel and Silicon Strip detectors, is designed to provide a precise measurement of the momentum of charged particles and to reconstruct the primary and secondary vertices. The movements of the different substructures of the tracker detectors driven by the operating conditions...
Article
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A bstract Motivated by the flavor anomalies in b → s transitions, we embed minimal models with a Z ′ gauge boson, vector-like fermions, and a singlet scalar in the framework of trans-Planckian asymptotic safety. The presence of a fixed point in the renormalization group flow of the models’ parameters leads to predictions for the γ/Z ′ kinetic mixin...
Preprint
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We present an evaluation of the standard model one-loop contributions to the $H^*Z^*Z^*$ coupling, where all three particles are taken off-shell. Our results are presented in terms of Passarino-Veltman scalar functions. We then use the most current CMS results to obtain bounds on the off-shell $H^*ZZ$ coupling, which at the one-loop level can be pa...
Article
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We investigate full off-shell effects in tt¯bb¯ production in the dilepton channel at the LHC with the center-of-mass energy s=13 TeV. Specifically, we compute next-to-leading-order (NLO) QCD corrections to the pp→e+νeμ−ν¯μbb¯bb¯+X process and provide a prescription for b-jet identification to distinguish prompt b jets from b jets originating from...
Article
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Direct photons provide a possibility to test properties of hot matter created in proton–proton (pp), proton–nucleus (p–A) or nucleus–nucleus (A–A) collisions. As they are created in charged particles’ scatterings and freely escape the hot region, they provide a tool to test all stages of the collision: the scattering of the partons of incoming nucl...
Preprint
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Central diffractive event topologies at the LHC energies can be identified by two different approaches. First, the forward scattered protons can be measured in Roman pots. Second, a veto on hadronic activity away from midrapidity can be imposed to define a double-gap topology. Such a double-gap topology trigger has been implemented by the ALICE col...
Article
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The emergence of chlorophyll-containing light-harvesting complexes (LHCs) was a crucial milestone in the evolution of photosynthetic eukaryotic organisms. Light-harvesting chlorophyll-binding proteins form complexes in proximity to the reaction centres of photosystems I and II and serve as an antenna, funnelling the harvested light energy towards t...
Preprint
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Models with an extended scalar electroweak sector are well motivated. Such models could accommodate a dark matter candidate if there is an additional scalar representation with a vanishing vacuum expectation value and, in addition, there are no couplings between fermions and the dark matter candidate. The most natural way to have these conditions i...
Article
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In the context of TeV-scale extensions of the Standard Model both the experimental searches and the construction of phenomenological models for the new heavy bosons searches are used by us. Heavy particles predicted by a the Simplified Model constructed to describe only the on-shell resonance, have to be compared with LHC data. Heavy bosons V' have...
Preprint
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A search for flavor-changing neutral-current couplings between a top quark, an up or charm quark and a $Z$ boson is presented, using proton-proton collision data at $\sqrt{s} = 13$ TeV collected by the ATLAS detector at the Large Hadron Collider. The analyzed dataset corresponds to an integrated luminosity of 139 fb$^{-1}$. The search targets both...
Article
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Motivated by recent experimental LHC measurements on the forward inclusive jet productions and based on our previous calculations on forward hadron productions, we calculate a single inclusive jet cross section in pA collisions at forward rapidity within the color glass condensate framework up to the next-to-leading order. Moreover, with the applic...
Article
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We study the production of a neutral Higgs boson at a Future Circular Collider in the electron-hadron mode (FCC-eh) through the leading process e-p→νehq assuming the decay channel h→cc¯, where h is the Standard Model (SM)-like state discovered at the Large Hadron Collider (LHC). This process is studied in the context of a 2-Higgs Doublet Model Type...
Article
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Drell-Yan production is one of the precision cornerstones of the LHC, serving as calibration for measurements such as the W-boson mass. Its extreme precision at the level of 1% challenges theory predictions at the highest level. We present the first independent calculation of Drell-Yan production at order αs3 in transverse-momentum (qT) resummation...
Preprint
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Heavy-flavour production measurements in pp collisions are important tools to test theoretical models based on perturbative quantum chromodymanics (pQCD) and to investigate the heavy-quark hadronization mechanisms. In ALICE, heavy quarks are measured via the hadronic and electronic decay channels at central rapidity (-0.9 $<$ $\textit{y}$ $<$ 0.9)...
Article
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Current searches for squarks are inefficient in cases when the squark does not directly decay to the lightest supersymmetric particle (LSP), because those decays are Yukawa suppressed. This occurs when producing the first two generations of squarks and when, at the same time, there are several electroweakinos lighter than those squarks. In this pap...
Preprint
Full-text available
In the context of TeV-scale extensions of the Standard Model both the experimental searches and the construction of phenomenological models for the new heavy bosons searches are used by us. Heavy particles predicted by a the Simplified Model constructed to describe only the on-shell resonance, have to be compared with LHC data. Heavy bosons have ce...
Preprint
Full-text available
We propose a new strategy for anomaly detection at the LHC based on unsupervised quantum machine learning algorithms. To accommodate the constraints on the problem size dictated by the limitations of current quantum hardware we develop a classical convolutional autoencoder. The designed quantum anomaly detection models, namely an unsupervised kerne...
Article
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A bstract We present the first analysis of top spin polarizations, $$ t\overline{t} $$ t t ¯ spin correlations, and $$ t\overline{t} $$ t t ¯ spin entanglement at the LHC in the context of the Standard Model Effective Field Theory, that goes beyond Leading Order QCD accuracy. The complete set of independent dimension-6 operators entering $$ t\overl...
Article
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We study the benefits of jet- and event-level deep learning methods in distinguishing vector boson fusion (VBF) from gluon-gluon fusion (GGF) Higgs production at the LHC. We show that a variety of classifiers (CNNs, attention-based networks) trained on the complete low-level inputs of the full event achieve significant performance gains over shallo...
Preprint
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Many extensions of the Standard Model predict the production of dark matter particles at the LHC. Sufficiently light dark matter particles may be produced in decays of the Higgs boson that would appear invisible to the detector. This Letter presents a statistical combination of searches for H $\rightarrow$ invisible decays where multiple production...
Preprint
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Recent developments on a deep learning feed-forward network for estimating elliptic flow ($v_2$) coefficients in heavy-ion collisions have shown us the prediction power of this technique. The success of the model is mainly the estimation of $v_2$ from final state particle kinematic information and learning the centrality and the transverse momentum...
Preprint
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In view of the forthcoming High-Luminosity phase of the LHC, next-to-next-to-next-to-leading (N$^3$LO) calculations for the most phenomenologically relevant processes become necessary. In this work, we take the first step towards this goal for H$+$jet production by computing the one- and two-loop helicity amplitudes for the two contributing process...
Preprint
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The purpose of this document is to define the specifications for the structure fabrication and assembly of MQXFA series magnets to be used by the US High-Luminosity LHC Accelerator Upgrade Project (AUP). Magnets fabricated according to these specifications are expected to allow MQXFA magnets to meet the MQXFA Functional Requirements Specification....
Preprint
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A model-independent search for new physics leading to final states containing $H\rightarrow\gamma\gamma$ decays is performed with 139 fb$^{-1}$ of $\sqrt{s}$ = 13 TeV pp collision data recorded by the ATLAS detector at the Large Hadron Collider at CERN. This search examines 22 final states categorized by the objects that are produced in association...
Preprint
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The LHC produces an intense beam of highly energetic neutrinos of all three flavors in the forward direction, and the Forward Physics Facility (FPF) has been proposed to house a suite of experiments taking advantage of this opportunity. In this study, we investigate the FPF's potential to probe the neutrino electromagnetic properties, including neu...
Article
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The protection of superconducting magnets is a very important issue and demanding challenge in the LHC and other superconducting accelerating facilities. The quench phenomenon can destroy components of the accelerator, and therefore this digital system was designed, implemented, tested, and installed near each superconducting magnet in the LHC tunn...
Preprint
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A glimpse into the most recent searches for Dark Matter at the LHC performed by the ATLAS and CMS collaborations is presented. The results covered in this document are all based on Run-2 proton-proton collision data recorded at $\sqrt{s}=13\text{ TeV}$ and corresponding to an integrated luminosity of just under 140 $\text{fb}^{-1}
Preprint
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The production of $\pi^\pm$, ${\rm K}^\pm$, and $(\overline{\rm p})$p is measured in pp collisions at $\sqrt{s} = 13$ TeV in different topological regions. Particle transverse momentum ($p_{\rm T}$) spectra are measured in the ``toward'', ``transverse'', and ``away'' angular regions defined with respect to the direction of the leading particle in t...
Preprint
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Particle accelerators and their key characteristics including size, energy scale, gradient, and efficiency are at the core of any revolutionary development in various fields including particle physics, bioimaging, and many more. [2,3,4] Recently, linear accelerators benefiting from nanoscale optical interactions have been truly proven to be practic...
Article
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This article reports on the inclusive production cross section of several quarkonium states, \(\textrm{J}/\psi \), \(\psi \mathrm{(2S)}\), \(\Upsilon \mathrm (1S)\), \(\Upsilon \mathrm{(2S)}\), and \(\Upsilon \mathrm{(3S)}\), measured with the ALICE detector at the LHC, in pp collisions at \(\sqrt{s} = 5.02\) TeV. The analysis is performed in the d...
Article
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We study the associated production of prompt J/ψ mesons and W or Z bosons within the factorization approach of nonrelativistic QCD (NRQCD) at next-to-leading order in αs, via intermediate color singlet S31[1] and P3J[1] and color octet S10[8], S31[8], and P3J[8] states. Requiring for our predictions to be compatible with recent ATLAS measurements y...
Preprint
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The use of pressurized bladders for stress control of superconducting magnets was firstly proposed at Lawrence Berkeley National Laboratory (LBNL) in the early 2000s. Since then, the so-called bladders and keys procedure has become one of the reference techniques for the assembly of high-field accelerator magnets and demonstrators. Exploiting the a...
Article
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We propose a new analytical expression for the transverse-momentum-dependent (TMD, or unintegrated) gluon density in the proton. Essential phenomenological parameters are extracted from the LHC data on inclusive hadron production in pp collisions at low transverse momenta pT≤1 GeV. The latter are described in the framework of a modified soft quark-...
Article
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Search for light (within the mass range 84–200 GeV) doubly charged Higgs bosons decaying into a pair of W bosons has been deemed challenging using the conventional LHC searches with leptons, jets, and missing transverse momentum in the final state. Such Higgses, together with slightly heavier singly-charged and neutral Higgses, when arranged in an...
Preprint
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By the end of October 2022, the US HL-LHC Accelerator Upgrade Project (AUP) had completed fabrication of ten MQXFA magnets and tested eight of them. The MQXFA magnets are the low beta quadrupole magnets to be used in the Q1 and Q3 Inner Triplet elements of the High Luminosity LHC. This AUP effort is shared by BNL, Fermilab, and LBNL, with strand ve...
Article
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Abstract We consider $$Z'$$ Z ′ s in heterotic string derived models and study $$Z'$$ Z ′ resonant production at the TeV scale at the Large Hadron Collider (LHC). We use various kinematic differential distributions for the Drell–Yan process at NNLO in QCD to explore the parameter space of such models and investigate $$Z'$$ Z ′ couplings. In particu...
Preprint
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In extended Higgs models, a discrete symmetry is needed in the quark sector to avoid tree-level flavor-changing neutral currents. However, this is not necessary the case in the lepton sector. We consider a model in which one Higgs couples to quarks and three others couple to the electron, muon and tau, respectively. This four-doublet model is prese...
Preprint
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In this paper, we study the potential of future colliders to explore the parameter space of heavy neutral leptons (HNLs) through the dipole portal. We consider hadron colliders such as the LHC in the high luminosity phase and FCC-hh, and lepton colliders, such as FCC-ee. We consider various signatures for the HNLs, including the missing energy sign...
Article
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The Standard Model (SM) of particle physics is the most general renormalizable theory which is built on a few general principles and fundamental symmetries with the given particle content. However, multiple symmetries are not built into the model and are simply consequences of renormalizabilty, gauge invariance, and particle content of the theory....
Article
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High energy collisions at the High-Luminosity Large Hadron Collider (LHC) produce a large number of particles along the beam collision axis, outside of the acceptance of existing LHC experiments. The proposed Forward Physics Facility (FPF), to be located several hundred meters from the ATLAS interaction point and shielded by concrete and rock, will...
Preprint
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A search for the pair production of the lightest supersymmetric partner of the top quark, the top squark ($\tilde{\mathrm{t}}_1$), is presented. The search targets the four-body decay of the $\tilde{\mathrm{t}}_1$, which is preferred when the mass difference between the top squark and the lightest supersymmetric particle is smaller than the mass of...
Preprint
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We extend a previous GTMD model to improve the description of the HERA data on diffractive dijet production, and include exclusive coherent diffractive $J/\psi$ production data. We find that within our gluon GTMD model context and assumptions, there is considerable tension between the data for these two types of processes concerning the $t$ depende...
Preprint
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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 $\sqrt{s_\mathrm{NN}}$ = 8.16 TeV, almost 300 times higher than in previous measure...
Article
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We study the possibility to observe heavy ( $$M_{\textrm{inst}}> 60$$ M inst > 60 GeV) QCD instantons at the LHC in events with one or two tagged leading protons including fast simulation of detector and pile-up effects. We show that the expected instanton signal in a single-tagged configuration is strongly affected by central detector and pile-up...
Preprint
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We investigate the consequences of models where dark sector quarks could be produced at the LHC, which subsequently undergo a dark parton shower, generating jets of dark hadrons that ultimately decay back to Standard Model hadrons. This yields collider objects that can be nearly indistinguishable from Standard Model jets, motivating the reliance on...
Article
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To cope with the challenges posed by the High-Luminosity LHC, the CMS experiment will feature a new silicon tracker. The modules of the upgraded inner tracker are hybrid silicon pixel modules based on a new readout chip, developed by the RD53 collaboration. Compared to the readout chip of the current pixel detector, the RD53 chip is capable of sust...
Thesis
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The Future Circular Hadron Collider (FCC-hh) is a proposal for a 100-kilometre-long particle accelerator with collision energy substantially higher than previous colliders to expand the Large Hadron Collider (LHC) research. The selection of a low surface impedance beam screen coating material for such a high-energy collider has become of fundamenta...
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Based on a nonequilibrium-statistical relativistic diffusion model that is consistent with quantum chromodynamics (QCD), we investigate baryon stopping in relativistic heavy-ion collisions at SPS, RHIC, and LHC energies. The net-proton rapidity distributions of the individual fragments exhibit a scaling behaviour similar to limiting fragmentation (...
Article
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Here we document physiological and molecular attributes of three wheat cultivars (ZM9023, YM158 and FM1228) under low light intensity with advanced technologies, including non-standard quantitative technology and quantitative proteomics technology. We found lower dry matter accumulation of YM158 compared with ZM 9023 and FM1228 under low light inte...
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The existence of dark matter is explained by a new neutral tensor gauge boson, Z μν-boson, of mass of 2.3 TeV. The Z μν-boson can be predicted by the tensor gauge boson extension of the Electro Weak (EW) theory proposed by G. Savvidy (2005). We compute the self-annihilation cross-section of the Z μν dark matter and calculate its relic abundance. We...
Article
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Type-2 diabetes (T2D) is characterised by a dysregulation of metabolism, including skeletal muscle insulin resistance, mitochondrial dysfunction, and oxidative stress. Reactive species, such as methylglyoxal (MGO) and 4-hydroxynonenal (4-HNE), positively associate with T2D disease severity and can directly interfere with insulin signalling and gluc...
Article
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A bstract Decays of Higgs boson-like particles into multileptons is a well-motivated process for investigating physics beyond the Standard Model (SM). A unique feature of this final state is the precision with which the SM is known. As a result, simulations are used directly to estimate the background. Current searches consider specific models and...