• Home
  • Vardan Khachatryan
Vardan Khachatryan

Vardan Khachatryan
  • A.I.Alikhanyan National Science Laboratory

About

986
Publications
1,541,833
Reads
How we measure 'reads'
A 'read' is counted each time someone views a publication summary (such as the title, abstract, and list of authors), clicks on a figure, or views or downloads the full-text. Learn more
53,492
Citations
Current institution
A.I.Alikhanyan National Science Laboratory

Publications

Publications (986)
Preprint
Full-text available
The total cross section for Compton scattering off atomic electrons, $\gamma+e\rightarrow\gamma'+e'$, was measured using photons with energies between 6.5 and 11.1~GeV incident on a $^9$Be target as part of the PrimEx-eta experiment in Hall D at Jefferson Lab. This is the first measurement of this fundamental QED process within this energy range. T...
Preprint
We measure for the first time the differential photoproduction cross section $d\sigma/dt$ of the $a_2(1320)$ meson at an average photon beam energy of 8.5~GeV, using data with an integrated luminosity of 104~pb$^{-1}$ collected by the GlueX experiment. We fully reconstruct the $\gamma p \to \eta\pi^0 p$ reaction and perform a partial-wave analysis...
Preprint
Full-text available
Measurements of the EMC effect in the tritium and helium-3 mirror nuclei are reported. The data were obtained by the MARATHON Jefferson Lab experiment, which performed deep inelastic electron scattering from deuterium and the three-body nuclei, using a cryogenic gas target system and the High Resolution Spectrometers of the Hall A Facility of the L...
Preprint
Full-text available
The spin-exotic hybrid meson $\pi_{1}(1600)$ is predicted to have a large decay rate to the $\omega\pi\pi$ final state. Using 76.6~pb$^{-1}$ of data collected with the GlueX detector, we measure the cross sections for the reactions $\gamma p \to \omega \pi^+ \pi^- p$, $\gamma p \to \omega \pi^0 \pi^0 p$, and $\gamma p\to\omega\pi^-\pi^0\Delta^{++}$...
Preprint
Full-text available
We report the measurement of spin-density matrix elements of the $\Delta^{++}(1232)$ in the photoproduction reaction $\gamma p \to \pi^-\Delta^{++}(1232)$ with the GlueX experiment in Hall D at Jefferson Lab. The measurement used a linearly polarized photon beam with $E_\gamma=8.2-8.8$~GeV and the statistical precision exceeds the previous measurem...
Article
Full-text available
The GlueX experiment at Jefferson Lab studies photoproduction of mesons using linearly polarized 8.5GeV photons impinging on a hydrogen target which is contained within a detector with near-complete coverage for charged and neutral particles. We present measurements of spin-density matrix elements for the photoproduction of the vector meson ρ(770)....
Article
We report the total and differential cross sections for J/ψ photoproduction with the large acceptance GlueX spectrometer for photon beam energies from the threshold at 8.2 GeV up to 11.44 GeV and over the full kinematic range of momentum transfer squared, t. Such coverage facilitates the extrapolation of the differential cross sections to the forwa...
Preprint
Full-text available
The GlueX experiment at Jefferson Lab studies photoproduction of mesons using linearly polarized $8.5\,\text{GeV}$ photons impinging on a hydrogen target which is contained within a detector with near-complete coverage for charged and neutral particles. We present measurements of spin-density matrix elements for the photoproduction of the vector me...
Preprint
Full-text available
We report the total and differential cross sections for $J/\psi$ photoproduction with the large acceptance GlueX spectrometer for photon beam energies from the threshold at 8.2~GeV up to 11.44~GeV and over the full kinematic range of momentum transfer squared, $t$. Such coverage facilitates the extrapolation of the differential cross sections to th...
Preprint
Full-text available
This whitepaper presents the research priorities decided on by attendees of the 2022 Town Meeting for Fundamental Symmetries, Neutrons and Neutrinos, which took place December 13-15, 2022 in Chapel Hill, NC, as part of the Nuclear Science Advisory Committee (NSAC) 2023 Long Range Planning process. A total of 275 scientists registered for the meetin...
Preprint
Full-text available
Hot QCD physics studies the nuclear strong force under extreme temperature and densities. Experimentally these conditions are achieved via high-energy collisions of heavy ions at the Relativistic Heavy Ion Collider (RHIC) and the Large Hadron Collider (LHC). In the past decade, a unique and substantial suite of data was collected at RHIC and the LH...
Preprint
Full-text available
A new electron scattering experiment (E12-21-003) to verify and understand the nature of hidden sector particles, with particular emphasis on the so-called X17 particle, has been approved at Jefferson Lab. The search for these particles is motivated by new hidden sector models introduced to account for a variety of experimental and observational pu...
Preprint
Full-text available
When protons and neutrons (nucleons) are bound into atomic nuclei, they are close enough together to feel significant attraction, or repulsion, from the strong, short-distance part of the nucleon-nucleon interaction. These strong interactions lead to hard collisions between nucleons, generating pairs of highly-energetic nucleons referred to as shor...
Article
Full-text available
When protons and neutrons (nucleons) are bound into atomic nuclei, they are close enough to feel significant attraction, or repulsion, from the strong, short-distance part of the nucleon–nucleon interaction. These strong interactions lead to hard collisions between nucleons, generating pairs of highly energetic nucleons referred to as short-range c...
Article
Full-text available
We report high-precision measurements of the deeply virtual Compton scattering (DVCS) cross section at high values of the Bjorken variable x_{B}. DVCS is sensitive to the generalized parton distributions of the nucleon, which provide a three-dimensional description of its internal constituents. Using the exact analytic expression of the DVCS cross...
Article
Full-text available
The ratio of the nucleon F_{2} structure functions, F_{2}^{n}/F_{2}^{p}, is determined by the MARATHON experiment from measurements of deep inelastic scattering of electrons from ^{3}H and ^{3}He nuclei. The experiment was performed in the Hall A Facility of Jefferson Lab using two high-resolution spectrometers for electron detection, and a cryogen...
Article
Full-text available
We present a search for axionlike particles, a, produced in photon-proton collisions at a center-of-mass energy of approximately 4 GeV, focusing on the scenario where the a-gluon coupling is dominant. The search uses a → γγ and a → π þ π − π 0 decays, and a data sample corresponding to an integrated luminosity of 168 pb −1 collected with the GlueX...
Article
Full-text available
We report new precision measurements of the elastic electron-proton scattering cross section for momentum transfer squared (Q^2) up to 15.75~GeV. These data allow for improved extraction of the proton magnetic form factor at high Q^2 and nearly double the Q^2range of direct longitudinal/transverse separated cross sections. A comparison of our resul...
Article
We report on the measurement of spin density matrix elements of the Λ(1520) in the photoproduction reaction γp→Λ(1520)K+, via its subsequent decay to K−p. The measurement was performed as part of the GlueX experimental program in Hall D at Jefferson Laboratory using a linearly polarized photon beam with Eγ=8.2GeV–8.8GeV. These are the first such me...
Preprint
Full-text available
We report high-precision measurements of the Deeply Virtual Compton Scattering (DVCS) cross section at high values of the Bjorken variable $x_B$. DVCS is sensitive to the Generalized Parton Distributions of the nucleon, which provide a three-dimensional description of its internal constituents. Using the exact analytic expression of the DVCS cross...
Article
Full-text available
We report measurements of the exclusive neutral pion electroproduction cross section off protons at large values of xB (0.36, 0.48, and 0.60) and Q2 (3.1 to 8.4 GeV2) obtained from Jefferson Lab Hall A experiment E12-06-014. The corresponding structure functions dσT/dt+εdσL/dt, dσTT/dt, dσLT/dt, and dσLT′/dt are extracted as a function of the proto...
Preprint
Full-text available
We present a search for axion-like particles, $a$, produced in photon-proton collisions at a center-of-mass energy of approximately 4 GeV, focusing on the scenario where the $a$-gluon coupling is dominant. The search uses $a\to\gamma\gamma$ and $a\to\pi^+\pi^-\pi^0$ decays, and a data sample corresponding to an integrated luminosity of 168 pb$^{-1}...
Preprint
In our quest for investigating the nature of dark matter from the way its constituents interact with ordinary matter, we propose an experiment using a \pbo ~calorimeter to search for or set new limits on the production rate of i) hidden sector dark matter mediator in the $3 - 60$ MeV mass range via their $e^+e^-$ decay (or $\gamma\gamma$ decay with...
Article
Positron beams, both polarized and unpolarized, are identified as important ingredients for the experimental programs at the next generation of lepton accelerators. In the context of the hadronic physics program at Jefferson Lab (JLab), positron beams are complementary, even essential, tools for a precise understanding of the electromagnetic struct...
Preprint
Full-text available
The ratio of the nucleon $F_2$ structure functions, $F_2^n/F_2^p$, is determined by the MARATHON experiment from measurements of deep inelastic scattering of electrons from $^3$H and $^3$He nuclei. The experiment was performed in the Hall A Facility of Jefferson Lab and used two high resolution spectrometers for electron detection, and a cryogenic...
Preprint
Full-text available
We report new precision measurements of the elastic electron-proton scattering cross section for momentum transfer squared (Q$^2$) up to 15.75~\gevsq. These data allow for improved extraction of the proton magnetic form factor at high Q$^2$ and nearly double the Q$^2$ range of direct longitudinal/transverse separated cross sections. A comparison of...
Article
Full-text available
The physics motivation, detector design, triggers, calibration, alignment, simulation, and overall performance of the very forward CASTOR calorimeter of the CMS experiment are reviewed. The CASTOR Cherenkov sampling calorimeter is located very close to the LHC beam line, at a radial distance of about 1 cm from the beam pipe, and at 14.4 m from the...
Article
Full-text available
We report the first measurement of the (e,e′p) three-body breakup reaction cross sections in helium-3 (He3) and tritium (H3) at large momentum transfer [⟨Q2⟩≈1.9 (GeV/c)2] and xB>1 kinematics, where the cross section should be sensitive to quasielastic (QE) scattering from single nucleons. The data cover missing momenta 40≤pmiss≤500 MeV/c that, in...
Preprint
We report the first measurement of the (e,e'p) three-body breakup reaction cross sections in Helium-3 ($^3$He) and Tritium ($^3$H) at large momentum transfer ($<Q^2> ~ 1.9$ (GeV/c)$^2$) and $x_B > 1$ kinematics, covering a missing momentum range of $40 \leq p_{miss} \leq 500$ MeV/c. The measured cross sections are compared with different plane-wave...
Article
Full-text available
We report the first measurement of the (e,e′p) reaction cross-section ratios for Helium-3 (He3), Tritium (H3), and Deuterium (d). The measurement covered a missing momentum range of 40≤pmiss≤550MeV/c, at large momentum transfer (〈Q2〉≈1.9 (GeV/c)2) and xB>1, which minimized contributions from non quasi-elastic (QE) reaction mechanisms. The data is c...
Preprint
We report the first measurement of the $(e,e'p)$ reaction cross-section ratio for Helium-3 ($^3$He) relative to Tritium ($^3$H). The measurement covered a missing momentum range of $40 \le p_{miss} \le 550$ MeV/$c$, at large momentum transfer ($\langle Q^2 \rangle \approx 1.9$ (GeV/$c$)$^2$) and $x_B>1$, which minimized contributions from non quasi...
Article
Full-text available
During 2015, the Relativistic Heavy Ion Collider (RHIC) provided collisions of transversely polarized protons with Au and Al nuclei for the first time, enabling the exploration of transverse-single-spin asymmetries with heavy nuclei. Large single-spin asymmetries in very forward neutron production have been previously observed in transversely polar...
Article
Full-text available
Measurements of the associated production of a \(\mathrm{Z}\) boson with at least one jet originating from a b quark in proton–proton collisions at \(\sqrt{s} = 8\,\text {TeV} \) are presented. Differential cross sections are measured with data collected by the CMS experiment corresponding to an integrated luminosity of 19.8\(\,\text {fb}^{-1}\). \...
Article
Full-text available
A search is presented for decays beyond the standard model of the 125 GeV Higgs bosons to a pair of light bosons, based on models with extended scalar sectors. Light boson masses between 5 and 62.5 GeV are probed in final states containing four τ leptons, two muons and two b quarks, or two muons and two τ leptons. The results are from data in proto...
Article
Provided here are the results of calculations of tagging jet identification in the process of Higgs boson production via the mechanism of coalescence of vector bosons with subsequent decay into τ-leptons (VBF H→τ⁻τ⁺) for different transverse segmentations against the parts of modernized hadronic calorimeter of Compact Muonic Solenoid in the Large H...
Article
Full-text available
Results are reported from a search for physics beyond the standard model in final states with at least three charged leptons, in any combination of electrons or muons. The data sample corresponds to an integrated luminosity of 2.3 fb−1 of proton–proton collisions at √s = 13 TeV, recorded by the CMS experiment at the LHC in 2015. Two jets are requir...
Article
Full-text available
A search for heavy narrow resonances decaying into four-lepton final states has been performed using proton–proton collision data at s=8TeV collected by the CMS experiment, corresponding to an integrated luminosity of 19.7fb−1. No excess of events over the standard model background expectation is observed. Upper limits for a benchmark model on the...
Article
Full-text available
Results are reported from a search for physics beyond the standard model in final states with at least three charged leptons, in any combination of electrons or muons. The data sample corresponds to an integrated luminosity of 2.3\(\,\text {fb}^{-1}\) of proton–proton collisions at \(\sqrt{s} =13\)\(\,\text {TeV}\), recorded by the CMS experiment a...
Article
Full-text available
We present measurements of the elliptic flow, $v_2$, as a function of transverse momentum ($p_T$), pseudorapidity ($\eta$), and centrality in $d$$+$Au collisions at $\sqrt{s_{_{NN}}}=$200, 62.4, 39, and 19.6 GeV. The beam-energy scan of $d$$+$Au collisions provides a testing ground for the onset of flow signatures in small collision systems. We mea...
Article
Full-text available
The differential cross sections for inclusive production of B+ hadrons are measured as a function of the B+ transverse momentum pTB and rapidity yB in pp collisions at a centre-of-mass energy of 13 TeV, using data collected by the CMS experiment that correspond to an integrated luminosity of 48.1 pb−1. The measurement uses the exclusive decay chann...
Article
Full-text available
A search for single production of vector-like top quark partners (T) decaying into a Higgs boson and a top quark is performed using data from pp collisions at a centre-of-mass energy of 13 TeV collected by the CMS experiment at the CERN LHC, corresponding to an integrated luminosity of 2.3 fb−1. The top quark decay includes an electron or a muon wh...
Article
Full-text available
A search for single production of vector-like top quark partners (T) decaying into a Higgs boson and a top quark is performed using data from pp collisions at a centre-of-mass energy of 13 TeV collected by the CMS experiment at the CERN LHC, corresponding to an integrated luminosity of 2.3 fb⁻¹. The top quark decay includes an electron or a muon wh...
Article
Full-text available
Two-particle correlations in pPb collisions at a nucleon-nucleon center-of-mass energy of 5.02TeV are studied as a function of the pseudorapidity separation (Δη) of the particle pair at small relative azimuthal angle (|Δϕ|<π/3). The correlations are decomposed into a jet component that dominates the short-range correlations (|Δη|<1), and a componen...
Article
Full-text available
A search is presented for supersymmetry in all-hadronic events with missing transverse momentum and tagged top quarks. The data sample was collected with the CMS detector at the LHC and corresponds to an integrated luminosity of 2.3 fb−1 of proton-proton collisions at a center-of-mass energy of 13 TeV. Search regions are defined using the propertie...
Article
Full-text available
Inclusive jet spectra from pp and PbPb collisions at a nucleon-nucleon center-of-mass energy of 2.76TeV, collected with the CMS detector at the CERN Large Hadron Collider, are presented. Jets are reconstructed with three different distance parameters (R=0.2, 0.3, and 0.4) for transverse momentum (pT) greater than 70GeV/c and pseudorapidity |η|<2. N...
Article
Full-text available
A measurement is presented of the cross section for the electroweak production of a Z boson and a photon in association with two jets in proton–proton collisions at √ s = 8 TeV. The Z bosons are identified through their decays to electron or muon pairs. The measurement is based on data collected with the CMS detector corresponding to an integrated...
Article
Full-text available
A search is presented for W′ bosons in events with an electron or muon and large missing transverse momentum, using proton–proton collision data at s=13 TeV collected with the CMS detector in 2015 and corresponding to an integrated luminosity of 2.3 fb⁻¹. No evidence of an excess of events relative to the standard model expectations is observed. Fo...
Article
Full-text available
The cross section for coherent photoproduction accompanied by at least one neutron on one side of the interaction point and no neutron activity on the other side, , is measured with the CMS experiment in ultra-peripheral PbPb collisions at . The analysis is based on a data sample corresponding to an integrated luminosity of 159 , collected during t...
Article
A method for experimental investigation of the effect of X-ray focusing inside a single crystal subject to temperature gradient is proposed. The definition of diffracted X-ray focusing inside the crystal is shown to increase depending on the value of temperature gradient.
Article
Full-text available
A measurement of electroweak-induced production of Wγ and two jets is performed, where the W boson decays leptonically. The data used in the analysis correspond to an integrated luminosity of 19.7 fb−1 collected by the CMS experiment in √ s = 8 TeV proton-proton collisions produced at the LHC. Candidate events are selected with exactly one muon or...
Article
Full-text available
The results of a search for new physics in final states with photons and missing transverse energy are reported. The study is based on a sample of proton–proton collisions collected at a center-ofmass energy of 13 TeV with the CMS detector in 2015, corresponding to an integrated luminosity of 2.3 fb−1. Final states with two photons and significant...
Article
Full-text available
A search for narrow resonances in dielectron and dimuon invariant mass spectra has been performed using data obtained from proton–proton collisions at s=13TeV collected with the CMS detector. The integrated luminosity for the dielectron sample is 2.7 fb−1 and for the dimuon sample 2.9 fb−1. The sensitivity of the search is increased by combining th...
Article
Full-text available
A search for heavy resonances decaying to a Higgs boson and a vector boson is presented. The analysis is performed using data samples collected in 2015 by the CMS experiment at the LHC in proton–proton collisions at a center-of-mass energy of 13 TeV, corresponding to integrated luminosities of 2.2–2.5 fb−1. The search is performed in channels in wh...
Article
A search for new phenomena is performed in final states containing one or more jets and an imbalance in transverse momentum in pp collisions at a centre-of-mass energy of 13 TeVTeV . The analysed data sample, recorded with the CMS detector at the CERN LHC, corresponds to an integrated luminosity of 2.3 fb−1fb−1 . Several kinematic variables are emp...
Article
Pair production of Y(1S) mesons is observed at the LHC in proton-proton collisions at s√=8s=8 TeV by the CMS experiment in a data sample corresponding to an integrated luminosity of 20.7 fb−1. Both Y(1S) candidates are fully reconstructed via their decays to μ+μ−. The fiducial acceptance region is defined by an absolute Y(1S) rapidity smaller than...
Article
Full-text available
Differential and double-differential cross sections for the production of top quark pairs in proton-proton collisions at 13 TeV are measured as a function of jet multiplicity and of kinematic variables of the top quarks and the top quark-antiquark system. This analysis is based on data collected by the CMS experiment at the LHC corresponding to an...
Article
Full-text available
A measurement is presented of the cross section for the electroweak production of a Z boson and a photon in association with two jets in proton-proton collisions at s=8TeV. The Z bosons are identified through their decays to electron or muon pairs. The measurement is based on data collected with the CMS detector corresponding to an integrated lumin...
Article
Full-text available
Pair production of Y(1S) mesons is observed at the LHC in proton-proton collisions at \( \sqrt{s}=8 \) TeV by the CMS experiment in a data sample corresponding to an integrated luminosity of 20.7 fb−1. Both Y(1S) candidates are fully reconstructed via their decays to μ+μ−. The fiducial acceptance region is defined by an absolute Y(1S) rapidity smal...
Article
Full-text available
The differential cross sections for inclusive production of B+ hadrons are measured as a function of the B+ transverse momentum pTB and rapidity yB in pp collisions at a centre-of-mass energy of 13 TeV, using data collected by the CMS experiment that correspond to an integrated luminosity of 48.1 pb⁻¹. The measurement uses the exclusive decay chann...
Article
An inclusive search is performed for supersymmetry in final states containing jets and an apparent imbalance in transverse momentum, p^→miss_T, due to the production of unobserved weakly interacting particles in pp collisions at a centre-of-mass energy of 8TeV. The data, recorded with the CMS detector at the CERN LHC, correspond to an integrated lu...
Article
Full-text available
An inclusive search is performed for supersymmetry in final states containing jets and an apparent imbalance in transverse momentum, p→Tmiss, due to the production of unobserved weakly interacting particles in pp collisions at a centre-of-mass energy of 8 TeV. The data, recorded with the CMS detector at the CERN LHC, correspond to an integrated lum...
Article
Full-text available
A search for the resonant production of high-mass photon pairs is presented. The search focuses on spin-0 and spin-2 resonances with masses between 0.5 and 4.5 TeV, and with widths, relative to the mass, between 1.4 × 10−4 and 5.6 × 10−2. The data sample corresponds to an integrated luminosity of 12.9 fb−1 of proton–proton collisions collected with...
Article
The spectra of charged particles produced within the pseudorapidity window |η| < 1 at √ sNN = 5.02 TeV are measured using 404 µb −1 of PbPb and 27.4 pb−1 of pp data collected by the CMS detector at the LHC in 2015. The spectra are presented over the transverse momentum ranges spanning 0.5 < pT < 400 GeV in pp and 0.7 < pT < 400 GeV in PbPb collisio...
Article
Full-text available
The spectra of charged particles produced within the pseudorapidity window |η| < 1 at \( \sqrt{s_{\mathrm{N}\;\mathrm{N}}}=5.02 \) TeV are measured using 404 μb−1 of PbPb and 27.4 pb−1 of pp data collected by the CMS detector at the LHC in 2015. The spectra are presented over the transverse momentum ranges spanning 0.5 < pT< 400 GeV in pp and 0.7 <...
Article
Full-text available
Cross sections for the production of a Z boson in association with jets in proton-proton collisions at a centre-of-mass energy of \( \sqrt{s}=8 \) TeV are measured using a data sample collected by the CMS experiment at the LHC corresponding to 19.6 fb−1. Differential cross sections are presented as functions of up to three observables that describe...
Article
Full-text available
Results are presented from a search for the electroweak production of supersymmetric particles in pp collisions in final states with two τ leptons. The data sample corresponds to an integrated luminosity between 18.1 fb−1 and 19.6 fb−1 depending on the final state of τ lepton decays, at \( \sqrt{s}=8 \) TeV, collected by the CMS experiment at the L...
Article
Full-text available
The WZ production cross section is measured by the CMS experiment at the CERN LHC in proton–proton collision data samples corresponding to integrated luminosities of 4.9\(\,\text{fb}^{-1}\) collected at \(\sqrt{s} = 7\,\text{TeV} \), and 19.6\(\,\text{fb}^{-1}\) at \(\sqrt{s} = 8\,\text{TeV} \). The measurements are performed using the fully-lepton...
Article
Full-text available
The production yields of ϒ(1S), ϒ(2S), and ϒ(3S) quarkonium states are measured through their decays into muon pairs in the CMS detector, in PbPb and pp collisions at the centre-of-mass energy per nucleon pair of 2.76TeV. The data correspond to integrated luminosities of 166μb−1and 5.4pb−1for PbPb and pp collisions, respectively. Differential produ...
Article
Full-text available
The invariance of the standard model (SM) under the CPT transformation predicts equality of particle and antiparticle masses. This prediction is tested by measuring the mass difference between the top quark and antiquark (Δmt=mt−mt‾) that are produced in pp collisions at a center-of-mass energy of 8 TeV, using events with a muon or an electron and...
Article
The nuclear modification factor RAA and the azimuthal anisotropy coefficient v2 of prompt and nonprompt (i.e. those from decays of b hadrons) J/ψ mesons, measured from PbPb and pp collisions at √sNN = 2.76 TeV at the LHC, are reported. The results are presented in several event centrality intervals and several kinematic regions, for transverse mome...
Article
Full-text available
A measurement of the double-differential inclusive jet cross section as a function of the jet transverse momentum pT and the absolute jet rapidity |y| is presented. Data from LHC proton-proton collisions at √ s = 8 TeV, corresponding to an integrated luminosity of 19.7 fb−1 , have been collected with the CMS detector. Jets are reconstructed using t...
Article
Full-text available
Charge-dependent azimuthal particle correlations with respect to the second-order event plane in p−Pb and PbPb collisions at a nucleon-nucleon center-of-mass energy of 5.02 TeV have been studied with the CMS experiment at the LHC. The measurement is performed with a three-particle correlation technique, using two particles with the same or opposite...
Article
The cross section of top quark-antiquark pair production in proton–proton collisions at √s = 13 TeV is measured by the CMS experiment at the LHC, using data corresponding to an integrated luminosity of 2.2 fb^(−1) . The measurement is performed by analyzing events in which the final state includes one electron, one muon, and two or more jets, at le...
Article
Full-text available
A search for new particles has been conducted using events with two high transverse momentum (pT) τ leptons that decay hadronically, at least two high-pT jets, and missing transverse energy from the τ lepton decays. The analysis is performed using data from proton-proton collisions, collected by the CMS experiment in 2015 at √ s = 13 TeV, correspon...
Article
Differential cross sections for a W boson produced in association with jets are measured in a data sample of proton-proton collisions at a center-of-mass energy of 8 TeV recorded with the CMS detector and corresponding to an integrated luminosity of 19.6 fb^(−1). The W bosons are identified through their decay mode W → μν. The cross sections are re...
Article
Full-text available
Differential cross sections for a W boson produced in association with jets are measured in a data sample of proton-proton collisions at a center-of-mass energy of 8 TeV recorded with the CMS detector and corresponding to an integrated luminosity of 19.6 fb−1. The W bosons are identified through their decay mode W → μν. The cross sections are repor...
Article
Full-text available
A search for new particles has been conducted using events with two high transverse momentum (pT) τ leptons that decay hadronically, at least two high-pT jets, and missing transverse energy from the τ lepton decays. The analysis is performed using data from proton-proton collisions, collected by the CMS experiment in 2015 at \( \sqrt{s}=13 \) TeV,...
Article
Full-text available
© 2017, CERN for the benefit of the CMS collaboration.The cross section of top quark–antiquark pair production in proton–proton collisions at s=13TeV is measured by the CMS experiment at the LHC, using data corresponding to an integrated luminosity of 2.2fb-1. The measurement is performed by analyzing events in which the final state includes one el...
Article
Full-text available
A measurement of the double-differential inclusive jet cross section as a function of the jet transverse momentum pT and the absolute jet rapidity |y| is presented. Data from LHC proton-proton collisions at \( \sqrt{s}=8 \) TeV, corresponding to an integrated luminosity of 19.7 fb−1, have been collected with the CMS detector. Jets are reconstructed...
Article
The results of a first search for CP violation in the production and decay of top quark-antiquark (tt¯) pairs are presented. The search is based on asymmetries in T-odd, triple-product correlation observables, where T is the time-reversal operator. The analysis uses a sample of proton-proton collisions at s=8 TeV collected by the CMS experiment, co...
Article
Full-text available
The nuclear modification factor \(R_{\mathrm{AA}}\) and the azimuthal anisotropy coefficient \(v_{2}\) of prompt and nonprompt (i.e. those from decays of b hadrons) \({\mathrm{J}}/\psi \) mesons, measured from PbPb and pp collisions at \(\sqrt{{s_{_{\text {NN}}}}} =2.76\)\(\,\mathrm{TeV}\) at the LHC, are reported. The results are presented in seve...
Article
Full-text available
A search for new phenomena is performed in final states containing one or more jets and an imbalance in transverse momentum in pp collisions at a centre-of-mass energy of 13\(\,\text {TeV}\). The analysed data sample, recorded with the CMS detector at the CERN LHC, corresponds to an integrated luminosity of 2.3\(\,\text {fb}^{-1}\). Several kinemat...
Article
The cross section for Higgs boson production in pp collisions is studied using the H → W+W− decay mode, followed by leptonic decays of the W bosons to an oppositely charged electron-muon pair in the final state. The measurements are performed using data collected by the CMS experiment at the LHC at a centre-of-mass energy of 8 TeV, corresponding to...
Article
Improved jet energy scale corrections, based on a data sample corresponding to an integrated luminosity of 19.7 fb^(-1) collected by the CMS experiment in proton-proton collisions at a center-of-mass energy of 8 TeV, are presented. The corrections as a function of pseudorapidity η and transverse momentum p_T are extracted from data and simulated ev...
Article
The transverse momentum spectra of weak vector bosons are measured in the CMS experiment at the LHC. The measurement uses a sample of proton-proton collisions at √s = 8 TeV, collected during a special low-luminosity running that corresponds to an integrated luminosity of 18.4 ± 0.5 pb^(-1). The production of W bosons is studied in both electron and...
Article
Full-text available
An inclusive search is performed for supersymmetry in final states containing jets and an apparent imbalance in transverse momentum, p→Tmiss, due to the production of unobserved weakly interacting particles in pp collisions at a centre-of-mass energy of 8 TeV. The data, recorded with the CMS detector at the CERN LHC, correspond to an integrated lum...
Article
Full-text available
The fraction of $J/\psi$ mesons which come from B-meson decay, $\textrm{F}_{B{\rightarrow}J/\psi}$, is measured for J/$\psi$ rapidity \mbox{$1.2<|y|<2.2$} and $p_T>0$ in $p$+$p$ and Cu+Au collisions at $\sqrt{s_{_{NN}}}$=200 GeV with the PHENIX detector. The extracted fraction is $\textrm{F}_{B{\rightarrow}J/\psi}$ = 0.025 $\pm$ 0.006(stat) $\pm$ 0...
Article
Full-text available
A search for narrow resonances in dielectron and dimuon invariant mass spectra has been performed using data obtained from proton–proton collisions at s=13 TeV collected with the CMS detector. The integrated luminosity for the dielectron sample is 2.7 fb⁻¹ and for the dimuon sample 2.9 fb⁻¹. The sensitivity of the search is increased by combining t...
Article
Full-text available
Measurements of strange hadron (KS0, Λ+Λ‾, and Ξ−+Ξ‾+) transverse momentum spectra in pp, pPb, and PbPb collisions are presented over a wide range of rapidity and event charged-particle multiplicity. The data were collected with the CMS detector at the CERN LHC in pp collisions at s=7TeV, pPb collisions at sNN=5.02TeV, and PbPb collisions at sNN=2....
Article
Full-text available
A search for heavy resonances decaying to a Higgs boson and a vector boson is presented. The analysis is performed using data samples collected in 2015 by the CMS experiment at the LHC in proton-proton collisions at a center-of-mass energy of 13 TeV, corresponding to integrated luminosities of 2.2–2.5 fb⁻¹. The search is performed in channels in wh...
Article
A search is performed for Higgs-boson-mediated flavor-changing neutral currents in the decays of top quarks. The search is based on proton-proton collision data corresponding to an integrated luminosity of 19.7 fb^(−1) at a center-of-mass energy of 8 TeV collected with the CMS detector at the LHC. Events in which a top quark pair is produced with o...
Article
A search for heavy resonances that decay to tau lepton pairs is performed using proton-proton collisions at √s = 13TeV. The data were collected with the CMS detector at the CERN LHC and correspond to an integrated luminosity of 2.2 fb^(−1). The observations are in agreement with standard model predictions. An upper limit at 95% confidence level on...
Article
This paper describes the search for a high-mass narrow-width scalar particle decaying into a Z boson and a photon. The analysis is performed using proton-proton collision data recorded with the CMS detector at the LHC at center-of-mass energies of 8 and 13 TeV, corresponding to integrated luminosities of 19.7 and 2.7 fb^(−1), respectively. The Z bo...
Article
Single top quark events produced in the t channel are used to set limits on anomalous Wtb couplings and to search for top quark flavour-changing neutral current (FCNC) interactions. The data taken with the CMS detector at the LHC in proton-proton collisions at s√ =7 and 8 TeV correspond to integrated luminosities of 5.0 and 19.7 fb^(−1), respective...

Network

Cited By