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Öğe Proton reconstruction with the totem roman pot detectors for high-β∗ lhc data(İnstitute of Physics, 2025) Hayrapetyan A.; Tumasyan A.; Adam W.; Andrejkovic J.W.; Benato L.; Sağır, SinanThe TOTEM Roman pot detectors are used to reconstruct the transverse momentum of scattered protons and to estimate the transverse location of the primary interaction. This paper presents new methods of track reconstruction, measurements of strip-level detection efficiencies, cross-checks of the LHC beam optics, and detector alignment techniques, along with their application in the selection of signal collision events. The track reconstruction is performed by exploiting hit cluster information through a novel method using a common polygonal area in the intercept-slope plane. The technique is applied in the relative alignment of detector layers with μm precision. A tag-and-probe method is used to extract strip-level detection efficiencies. The alignment of the Roman pot system is performed through time-dependent adjustments, resulting in a position accuracy of 3 μm in the horizontal and 60 μm in the vertical directions. The goal is to provide an optimal reconstruction tool for central exclusive physics analyses based on the high-β∗ data-taking period at √s = 13 TeV in 2018. © 2025 CERN. Published by IOP Publishing Ltd on behalf of Sissa Medialab.Öğe Energy-scaling behavior of intrinsic transverse-momentum parameters in drell-yan simulation(American Physical Society, 2025) Hayrapetyan A.; Tumasyan A.; Adam W.; Andrejkovic J.W.; Bergauer T. b; Sağır, SinanAn analysis is presented based on models of the intrinsic transverse momentum (intrinsic (Formula presented)) of partons in nucleons by studying the dilepton transverse momentum in Drell-Yan events. Using parameter tuning in event generators and existing data from fixed-target experiments and from hadron colliders, our investigation spans 3 orders of magnitude in center-of-mass energy and 2 orders of magnitude in dilepton invariant mass. The results show an energy-scaling behavior of the intrinsic (Formula presented) parameters, independent of the dilepton invariant mass at a given center-of-mass energy. © 2025 CERN, for the CMS Collaboration.Öğe Search for fractionally charged particles in proton-proton collisions at (formula presented)(American Physical Society, 2025) Hayrapetyan A.; Tumasyan A.; Adam W.; Andrejkovic J.W.; Bergauer T.; Sağır, SinanA search is presented for fractionally charged particles with charges below (Formula presented), using their small energy loss in the tracking detector as a key variable to observe a signal. The analyzed dataset corresponds to an integrated luminosity of (Formula presented) of proton-proton collisions collected at (Formula presented) in 2016-2018 at the CERN LHC. This is the first search at the LHC for new particles with a charge between (Formula presented) and (Formula presented), including an extension of previous results at a charge of (Formula presented). Masses up to 640 GeV and charges as low as (Formula presented) are excluded at 95% confidence level. These are the most stringent limits to date for the considered Drell-Yan-like production mode. © 2025 CERN, for the CMS Collaboration.Öğe Constraints on the higgs boson self-coupling from the combination of single and double higgs boson production in proton-proton collisions at √s=13 tev(Elsevier, 2025) Hayrapetyan, A; Tumasyan, A.; Adam, W.; Andrejkovic, J. W.; Bergauer, T.; Chatterjee, S.; Sağır, SinanThe Higgs boson (H) trilinear self-coupling, lambda(3), is constrained via its measured properties and limits on the HH pair production using the proton-proton collision data collected by the CMS experiment at root s = 13 TeV. The combination of event categories enriched in single-H and HH events is used to measure k(lambda), defined as the value of lambda(3) normalized to its standard model prediction, while simultaneously constraining the Higgs boson couplings to fermions and vector bosons. Values of k(lambda) outside the interval -1.2 < k(lambda) < 7.5 are excluded at 2 sigma confidence level, which is compatible with the expected range of -2.0< k(lambda) < 7.7 under the assumption that all other Higgs boson couplings are equal to their standard model predicted values. Relaxing the assumption on the Higgs couplings to fermions and vector bosons the observed (expected) k(lambda) interval is constrained to be within -1.4 < k(lambda) < 7.8 (-2.3 < k(lambda) < 7.8) at 2 sigma confidence level.Öğe Kinect-based anthropometric measurements: a comparative analysis of traditional methods in youth female weightlifters(Bmc, 2025) Örücü, Serkan; Işık, Bülent; Erdağı, Kenan; Osmanoğlu, Usame Ömer; Özbay, ErkanBackgroundThe importance of anthropometric measurements for monitoring the physical development of athletes and optimizing training programs is well known. Considering the limitations of traditional methods in terms of accuracy and consistency, the aim of this study is to investigate the potential of Kinect V2 as an alternative.MethodsThis study wasperformed on 12 youth female weightlifters who won medals in the Youth European Weightlifting Championship. Humerus length, forearm length, hand length, trochanter-tibiale laterale length, tibial length and shoulder width measurements were performed with both Kinect V2 and manual methods. Statistical differences between groups were evaluated using the Mann-Whitney U test. The consistencies of the measurement methods were analyzed with Bland-Altman plots, correlations were determined with Pearson correlation coefficients, and reliability were evaluated with Intraclass Correlation Coefficient (ICC) values.ResultsKinect V2 provided accuracy and consistency comparable to manual methods in measurements of humerus (ICC = 0.532), forearm (ICC = 0.600), and hand length (ICC = 0.760). While medium-level concordance was observed in trochanter-tibiale lateral length measurements (ICC = 0.749), high-level concordance and reliability were found in tibial length (ICC = 0.914) and shoulder width (ICC = 0.869) measurements.ConclusionsThere were significant differences between the results of humerus length, forearm length and trochanter-tibiale laterale length obtained with both measurement methods. Therefore, measurements of these parameters require significant care. Findings of this study suggest that Kinect V2 can be a reliable tool for rapid and practical anthropometric assessments in sports settings, but highlight the importance of careful calibration and adjustments for specific measurements. Future studies should examine the use of this device more comprehensively across different sports and populations.Öğe Girth and groomed radius of jets recoiling against isolated photons in lead-lead and proton-proton collisions at √snn=5.02 tev(Elsevier, 2025) Hayrapetyan, A.; Tumasyan, A.; Adam, W.; Andrejkovic, J. W.; Bergauer, T; Sağır, SinanThis Letter presents the first measurements of the groomed jet radius R-g and the jet girth g in events with an isolated photon recoiling against a jet in lead-lead (PbPb) and proton-proton (pp) collisions at the LHC at a nucleon-nucleon center-of-mass energy of 5.02 TeV. The observables R-g and g provide a quantitative measure of how narrow or broad a jet is. The analysis uses PbPb and pp data samples with integrated luminosities of 1.7 nb(-1) and 301 pb(-1), respectively, collected with the CMS experiment in 2018 and 2017. Events are required to have a photon with transverse momentum p(T)(gamma) > 100 GeV and at least one jet back-to-back in azimuth with respect to the photon and with transverse momentum p(T)(jet) such that p(T)(jet)/p(T)(gamma) > 0.4. The measured R-g and g distributions are unfolded to the particle level, which facilitates the comparison between the PbPb and pp results and with theoretical predictions. It is found that jets with p(T)(jet)/p(T)(gamma) > 0.8, i.e., those that closely balance the photon p(T)(gamma), are narrower in PbPb than in pp collisions. Relaxing the selection to include jets with p(T)(jet)/p(T)(gamma) > 0.4 reduces the narrowing of the angular structure of jets in PbPb relative to the pp reference. This shows that selection bias effects associated with jet energy loss play an important role in the interpretation of jet substructure measurements.Öğe Consistency problems of conformal killing gravity(Amer Physical Soc, 2025) Altaş, Emel; Tekin, BayramWe show that gravity field equations based on a tensor with rank greater than 2 have consistency problems in the sense that integration constants in the solutions, such as the parameter m in the Schwarzschild metric, do not allow for an interpretation in terms of conserved quantities in the theory. The recently introduced conformal Killing gravity, an interesting extension of general relativity that inherits all the solutions of the latter, and defined with a rank-3 tensor field equation that does not arise from a diffeomorphism-invariant action, is plagued with this problem. In this theory, it is not clear at all how one can define the energy and angular momentum for black hole solutions, or define the analogs of the formulas, such as the quadrupole formula, in the weak field limit for gravitational waves emitted by compact sources.Öğe Model-independent search for pair production of new bosons decaying into muons in proton-proton collisions at √s=13 tev(Springer, 2025) Hayrapetyan, A.; Tumasyan, A.; Adam, W; Andrejkovic, J. W.; Bergauer, T; Sağır, SinanThe results of a model-independent search for the pair production of new bosons within a mass range of 0.21 < m < 60 GeV, are presented. This study utilizes events with a four-muon final state. We use two data sets, comprising 41.5 fb(-1) and 59.7 fb(-1) of proton-proton collisions at root s = 13TeV, recorded in 2017 and 2018 by the CMS experiment at the CERN LHC. The study of the 2018 data set includes a search for displaced signatures of a new boson within the proper decay length range of 0 < c tau < 100mm. Our results are combined with a previous CMS result, based on 35.9 fb(-1) of proton-proton collisions at root s = 13TeV collected in 2016. No significant deviation from the expected background is observed. Results are presented in terms of a model-independent upper limit on the product of cross section, branching fraction, and acceptance. The findings are interpreted across various benchmark models, such as an axion-like particle model, a vector portal model, the next-to-minimal supersymmetric standard model, and a dark supersymmetric scenario, including those predicting a non-negligible proper decay length of the new boson. In all considered scenarios, substantial portions of the parameter space are excluded, expanding upon prior results.Öğe Measurement of the double-differential inclusive jet cross section in proton-proton collisions at s = 5.02 tev(Springer Science and Business Media Deutschland GmbH, 2025) Hayrapetyan A; Tumasyan A; Adam W; Andrejkovic J.W; Bergauer T; Sağır, SinanThe inclusive jet cross section is measured as a function of jet transverse momentum pT and rapidity y. The measurement is performed using proton-proton collision data at s = 5.02 TeV, recorded by the CMS experiment at the LHC, corresponding to an integrated luminosity of 27.4 pb−1. The jets are reconstructed with the anti-kT algorithm using a distance parameter of R = 0.4, within the rapidity interval |y| < 2, and across the kinematic range 0.06 < pT< 1 TeV. The jet cross section is unfolded from detector to particle level using the determined jet response and resolution. The results are compared to predictions of perturbative quantum chromodynamics, calculated at both next-to-leading order and next-to-next-to-leading order. The predictions are corrected for nonperturbative effects, and presented for a variety of parton distribution functions and choices of the renormalization/factorization scales and the strong coupling αS. © The Author(s) 2025.Öğe Search for long-lived heavy neutral leptons in proton-proton collision events with a lepton-jet pair associated with a secondary vertex at s = 13 tev(Springer Science and Business Media Deutschland GmbH, 2025) Hayrapetyan A.; Tumasyan A; Adam W; Andrejkovic J.W; Bergauer T; Sağır, SinanA search for long-lived heavy neutral leptons (HNLs) using proton-proton collision data corresponding to an integrated luminosity of 138 fb−1 collected at s = 13 TeV with the CMS detector at the CERN LHC is presented. Events are selected with a charged lepton originating from the primary vertex associated with the proton-proton interaction, as well as a second charged lepton and a hadronic jet associated with a secondary vertex that corresponds to the semileptonic decay of a long-lived HNL. No excess of events above the standard model expectation is observed. Exclusion limits at 95% confidence level are evaluated for HNLs that mix with electron and/or muon neutrinos. Limits are presented in the mass range of 1–16.5 GeV, with excluded square mixing parameter values reaching as low as 2 × 10−7. For masses above 11 GeV, the presented limits exceed all previous results in the semileptonic decay channel, and for some of the considered scenarios are the strongest to date. © The Author(s) 2025.Öğe Test of lepton flavor universality in semileptonic (formula presented) meson decays in proton-proton collisions at (formula presented)(American Physical Society, 2025) Hayrapetyan A; Tumasyan A.; Adam W; Andrejkovic J.W; Bergauer T.; Sağır, SinanA measurement of the ratio of branching fractions (Formula presented) in the (Formula presented), (Formula presented) decay channel is presented. This measurement uses a sample of proton-proton collision data collected at a center-of-mass energy of (Formula presented) by the CMS experiment in 2018, corresponding to an integrated luminosity of (Formula presented). The measured ratio, (Formula presented), agrees with the value of (Formula presented) predicted by the standard model, which assumes lepton flavor universality. By testing lepton flavor universality, this measurement is a probe of new physics using (Formula presented) mesons, which are currently only produced at the LHC. © 2025 CERN, for the CMS CollaborationÖğe Search for nuclear modifications of (formula presented) meson production in (formula presented)-pb collisions at (formula presented)(American Physical Society, 2025) Hayrapetyan A; Tumasyan A.; Adam W.; Andrejkovic J.W.; Bergauer T.; Sağır, SinanNuclear medium effects on (Formula presented) meson production are studied using the binary-collision scaled cross section ratio between events of different charged-particle multiplicities from proton-lead collisions. Data, collected by the CMS experiment in 2016 at a nucleon-nucleon center-of-mass energy of (Formula presented), corresponding to an integrated luminosity of (Formula presented), were used. The scaling factors in the ratio are determined using a novel approach based on the (Formula presented) cross sections measured in the same events. The scaled ratio for (Formula presented) is consistent with unity for all event multiplicities, putting stringent constraints on nuclear modification for heavy flavor. © 2025 CERN, for the CMS Collaboration.Öğe Search for light long-lived particles decaying to displaced jets in proton-proton collisions at √s = 13.6 tev(Institute of Physics, 2025) Hayrapetyan A.; Sağır, Sinan; CMS Collaboration; Adam, W; Andrejkovic, W.; Bergauer, T.A search for light long-lived particles (LLPs) decaying to displaced jets is presented, using a data sample of proton-proton collisions at a center-of-mass energy of 13.6 TeV, corresponding to an integrated luminosity of 34.7 fb−1, collected with the CMS detector at the CERN LHC in 2022. Novel trigger, reconstruction, and machine-learning techniques were developed for and employed in this search. After all selections, the observations are consistent with the background predictions. Limits are presented on the branching fraction of the Higgs boson to LLPs that subsequently decay to quark pairs or tau lepton pairs. An improvement by up to a factor of 10 is achieved over previous limits for models with LLP masses smaller than 60 GeV and proper decay lengths smaller than 1 m. The first constraints are placed on the fraternal twin Higgs (FTH) and folded supersymmetry (FSUSY) models, where the lower bounds on the top quark partner mass reach up to 350 GeV for the FTH model and 250 GeV for the FSUSY model. © 2025 The Author(s). Published by IOP Publishing Ltd.Öğe Search for charged-lepton flavor violation in the production and decay of top quarks using trilepton final states in proton-proton collisions at (Formula presented)(American Physical Society, 2025) Hayrapetyan. A.; Sağır,SinanA search is performed for charged-lepton flavor violating processes in top quark ((Formula presented)) production and decay. The data were collected by the CMS experiment from proton-proton collisions at a center-of-mass energy of 13 TeV and correspond to an integrated luminosity of (Formula presented). The selected events are required to contain one opposite-sign electron-muon pair, a third charged lepton (electron or muon), and at least one jet of which no more than one is associated with a bottom quark. Boosted decision trees are used to distinguish signal from background, exploiting differences in the kinematics of the final states particles. The data are consistent with the standard model expectation. Upper limits at 95% confidence level are placed in the context of effective field theory on the Wilson coefficients, which range between (Formula presented) depending on the flavor of the associated light quark and the Lorentz structure of the interaction. These limits are converted to upper limits on branching fractions involving up (charm) quarks, (Formula presented) ((Formula presented)), of (Formula presented), (Formula presented), and (Formula presented) for tensorlike, vectorlike, and scalarlike interactions, respectively. © 2025 CERN, for the CMS Collaboration.Öğe Measurement of inclusive and differential cross sections for w+w- production in proton-proton collisions at √s=13.6 tev(2025) Hayrapetyan, A.; Tumasyan, A.; Adam, W.; Andrejkovic, J. W; Bergauer, T.; Chatterjee, S.; Sağır, SinanMeasurements at root s = 13.6 TeV of the opposite-sign W boson pair production cross section in proton-proton collisions are presented. The data used in this study were collected with the CMS detector at the CERN LHC in 2022, and correspond to an integrated luminosity of 34.8 fb(-1). Events are selected by requiring one electron and one muon of opposite charge. A maximum likelihood fit is performed on signal- and background-enriched data categories dfined by the flavor and charge of the leptons, the number of jets, and number of jets originating from b quarks. The overall sensitivity is significantly better than that of previous results with a similar integrated luminosity. The improvement comes from a more rfined control of experimental uncertainties and an improved fit strategy. An inclusive W+W- production cross section of 125.7 +/- 5.6 pb is measured, in agreement with standard model predictions. Cross sections are also reported in a fiducial region close to that of the detector acceptance, both inclusively and differentially, as a function of the jet multiplicity in the event. For the first time in proton-proton collisions, WWevents with zero, one, and at least two jets are studied simultaneously and compared with recent theoretical predictions.Öğe Search for central exclusive production of top quark pairs in proton-proton collisions at √s=13 tev with tagged protons(Springer, 2025) Tumasyan, A.; Adam, W.; Andrejkovic, J. W.; Bergauer, T.; Chatterjee, S.; Sağır, SinanA search for the central exclusive production of top quark-antiquark pairs (t (t) over bar) is performed for the first time using proton-tagged events in proton-proton collisions at the LHC at a centre-of-mass energy of 13TeV. The data correspond to an integrated luminosity of 29.4 fb(-1). The t (t) over bar decay products are reconstructed using the central CMS detector, while forward protons are measured in the CMS-TOTEM precision proton spectrometer. An observed (expected) upper bound on the production cross section of 0.59 (1.14) pb is set at 95% confidence level, for collisions of protons with fractional momentum losses between 2 and 20%.Öğe Search for a standard model-like Higgs boson in the mass range between 70 and 110 GeV in the diphoton final state in proton-proton collisions at √s=13 TeV(Elsevier, 2025) Hayrapetyan, A.; Sağır, SinanThe results of a search for a standard model-like Higgs boson decaying into two photons in the mass range between 70 and 110 GeV are presented. The analysis uses the data set collected by the CMS experiment in proton-proton collisions at root s = 13 TeV corresponding to integrated luminosities of 36.3 fb(-1), 41.5 fb(-1) and 54.4 fb(-1) during the 2016, 2017, and 2018 LHC running periods, respectively. No significant excess over the background expectation is observed and 95% cofidence level upper limits are set on the product of the cross section and branching fraction for decays of an additional Higgs boson into two photons. The maximum deviation with respect to the background is seen for a mass hypothesis of 95.4 GeV with a local (global) significance of 2.9 (1.3) standard deviations. The observed upper limit ranges from 15 to 73 fb.Öğe Measurement of boosted Higgs bosons produced via vector boson fusion or gluon fusion in the H → b(b)over-bar decay mode using LHC proton-proton collision data at √s=13 TeV(Springer, 2024) Hayrapetyan, A.; Sağır, SinanA measurement is performed of Higgs bosons produced with high transverse momentum (p(T)) via vector boson or gluon fusion in proton-proton collisions. The result is based on a data set with a center-of-mass energy of 13 TeV collected in 2016-2018 with the CMS detector at the LHC and corresponds to an integrated luminosity of 138 fb(-1). The decay of a high-p(T) Higgs boson to a boosted bottom quark-antiquark pair is selected using large-radius jets and employing jet substructure and heavy-flavor taggers based on machine learning techniques. Independent regions targeting the vector boson and gluon fusion mechanisms are defined based on the topology of two quark-initiated jets with large pseudorapidity separation. The signal strengths for both processes are extracted simultaneously by performing a maximum likelihood fit to data in the large-radius jet mass distribution. The observed signal strengths relative to the standard model expectation are 4.9(-1.6)(+1.9) and 1.6(-1.5)(+1.7) for the vector boson and gluon fusion mechanisms, respectively. A differential cross section measurement is also reported in the simplified template cross section framework.Öğe Search for Higgs boson pair production in the b(b)over-bar W+W- decay mode in proton-proton collisions at √s=13 TeV(Springer, 2024) Hayrapetyan, A.; Sağır, SinanA search for Higgs boson pair (HH) production with one Higgs boson decaying to two bottom quarks and the other to two W bosons are presented. The search is done using proton-proton collisions data at a centre-of-mass energy of 13TeV, corresponding to an integrated luminosity of 138 fb(-1) recorded by the CMS detector at the LHC from 2016 to 2018. The final states considered include at least one leptonically decaying W boson. No evidence for the presence of a signal is observed and corresponding upper limits on the HH production cross section are derived. The limit on the inclusive cross section of the nonresonant HH production, assuming that the distributions of kinematic observables are as expected in the standard model (SM), is observed (expected) to be 14 (18) times the value predicted by the SM, at 95% confidence level. The limits on the cross section are also presented as functions of various Higgs boson coupling modifiers, and anomalous Higgs boson coupling scenarios. In addition, limits are set on the resonant HH production via spin-0 and spin-2 resonances within the mass range 250-900 GeV.Öğe Search for bottom quark associated production of the standard model Higgs boson in final states with leptons in proton-proton collisions at √s=13 TeV(2024) Hayrapetyan, A.; Sağır, SinanThis Letter presents the first search for bottom quark associated production of the standard model Higgs boson, in final states with leptons. Higgs boson decays to pairs of tau leptons and pairs of leptonically decaying W bosons are considered. The search is performed using data collected from 2016 to 2018 by the CMS experiment in proton-proton collisions at a centre-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 138 fb(-1). Upper limits at the 95% confidence level are placed on the signal strength for Higgs boson production in association with bottom quarks; the observed (expected) upper limit is 3.7 (6.1) times the standard model prediction.
