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Full-Text Articles in Physics

Search For Associated Production Of A Z Boson With A Single Top Quark And For Tz Flavour-Changing Interactions In Pp Collisions At √S=8 Tev, M M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, D Noonan, Tuhin S. Roy, Francisco X. Yumiceva, Cms Collaboration Jul 2017

Search For Associated Production Of A Z Boson With A Single Top Quark And For Tz Flavour-Changing Interactions In Pp Collisions At √S=8 Tev, M M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, D Noonan, Tuhin S. Roy, Francisco X. Yumiceva, Cms Collaboration

Aerospace, Physics, and Space Science Faculty Publications

A search for the production of a single top quark in association with a Z boson is presented, both to identify the expected standard model process and to search for flavour-changing neutral current interactions. The data sample corresponds to an integrated luminosity of 19.7 fb−1 recorded by the CMS experiment at the LHC in proton-proton collisions at s=8 TeV. Final states with three leptons (electrons or muons) and at least one jet are investigated. An events yield compatible with tZq standard model production is observed, and the corresponding cross section is measured to be σ(pp → tZq → ℓνbℓ+ℓ−q) = …


Search For T T ¯ Resonances In Highly Boosted Lepton+Jets And Fully Hadronic Final States In Proton-Proton Collisions At √S=13 Tev, M M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, D Noonan, Tuhin S. Roy, Francisco X. Yumiceva, Cms Collaboration Jul 2017

Search For T T ¯ Resonances In Highly Boosted Lepton+Jets And Fully Hadronic Final States In Proton-Proton Collisions At √S=13 Tev, M M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, D Noonan, Tuhin S. Roy, Francisco X. Yumiceva, Cms Collaboration

Aerospace, Physics, and Space Science Faculty Publications

A search for the production of heavy resonances decaying into top quark-antiquark pairs is presented. The analysis is performed in the lepton+jets and fully hadronic channels using data collected in proton-proton collisions at s=13 TeV using the CMS detector at the LHC, corresponding to an integrated luminosity of 2.6 fb−1. The selection is optimized for massive resonances, where the top quarks have large Lorentz boosts. No evidence for resonant t t ¯ production is found in the data, and upper limits on the production cross section of heavy resonances are set. The exclusion limits for resonances with masses above 2 …


Compact Resolved Ejecta In The Nearest Tidal Disruption Event, Eric S. Perlman, Eileen T. Meyer, Q. Daniel Wang, Qiang Yuan, Richard N. Henriksen, Judith A. Irwin, Marita Krause, Theresa Wiegert, Eric J. Murphy, George H. Heald, Ralf-Jürgen Dettmar Jun 2017

Compact Resolved Ejecta In The Nearest Tidal Disruption Event, Eric S. Perlman, Eileen T. Meyer, Q. Daniel Wang, Qiang Yuan, Richard N. Henriksen, Judith A. Irwin, Marita Krause, Theresa Wiegert, Eric J. Murphy, George H. Heald, Ralf-Jürgen Dettmar

Aerospace, Physics, and Space Science Faculty Publications

Tidal disruption events (TDEs) occur when a star or substellar object passes close enough to a galaxy's supermassive black hole to be disrupted by tidal forces. NGC 4845 (d = 17 Mpc) was host to a TDE, IGR J12580+0134, detected in 2010 November. Its proximity offers us a unique close-up of the TDE and its aftermath. We discuss new Very Long Baseline Array (VLBA) and Karl G. Jansky Very Large Array observations, which show that the radio flux from the active nucleus created by the TDE has decayed in a manner consistent with predictions from a jet-circumnuclear medium interaction model. …


Measurement Of Electroweak-Induced Production Of Wγ With Two Jets In Pp Collisions At √S=8 Tev And Constraints On Anomalous Quartic Gauge Couplings, M M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, D Noonan, Tuhin S. Roy, Francisco X. Yumiceva, Cms Collaboration Jun 2017

Measurement Of Electroweak-Induced Production Of Wγ With Two Jets In Pp Collisions At √S=8 Tev And Constraints On Anomalous Quartic Gauge Couplings, M M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, D Noonan, Tuhin S. Roy, Francisco X. Yumiceva, Cms Collaboration

Aerospace, Physics, and Space Science Faculty Publications

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 electron, missing transverse momentum, one photon, and two jets with large rapidity separation. An excess over the hypothesis of the standard model without electroweak production of Wγ with two jets is observed with a significance of 2.7 standard deviations. The cross section measured in the …


Measurement Of The Top Quark Mass Using Single Top Quark Events In Proton-Proton Collisions At √S=8 Tev, M M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, D Noonan, Tuhin S. Roy, Francisco X. Yumiceva, Cms Collaboration May 2017

Measurement Of The Top Quark Mass Using Single Top Quark Events In Proton-Proton Collisions At √S=8 Tev, M M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, D Noonan, Tuhin S. Roy, Francisco X. Yumiceva, Cms Collaboration

Aerospace, Physics, and Space Science Faculty Publications

A measurement of the top quark mass is reported in events containing a single top quark produced via the electroweak t channel. The analysis is performed using data from proton-proton collisions collected with the CMS detector at the LHC at a centre-of-mass energy of 8 TeV, corresponding to an integrated luminosity of 19.7 fb- 1. Top quark candidates are reconstructed from their decay to a W boson and a b quark, with the W boson decaying leptonically to a muon and a neutrino. The final state signature and kinematic properties of single top quark events in the t channel are …


Searches For Pair Production Of Third-Generation Squarks In √S=13tev Pp Collisions, M M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, D Noonan, Tuhin S. Roy, Francisco X. Yumiceva, Cms Collaboration May 2017

Searches For Pair Production Of Third-Generation Squarks In √S=13tev Pp Collisions, M M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, D Noonan, Tuhin S. Roy, Francisco X. Yumiceva, Cms Collaboration

Aerospace, Physics, and Space Science Faculty Publications

Searches are presented for direct production of top or bottom squark pairs in proton–proton collisions at the CERN LHC. Two searches, based on complementary techniques, are performed in all-jet final states that are characterized by a significant imbalance in transverse momentum. An additional search requires the presence of a charged lepton isolated from other activity in the event. The data were collected in 2015 at a centre-of-mass energy of 13TeV with the CMS detector and correspond to an integrated luminosity of 2.3fb-1. No statistically significant excess of events is found beyond the expected contribution from standard model processes. Exclusion limits …


A Search For New Phenomena In Pp Collisions At √S=13tev In Final States With Missing Transverse Momentum And At Least One Jet Using The Αt Variable, M M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, D Noonan, Tuhin S. Roy, Francisco X. Yumiceva, Cms Collaboration May 2017

A Search For New Phenomena In Pp Collisions At √S=13tev In Final States With Missing Transverse Momentum And At Least One Jet Using The Αt Variable, M M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, D Noonan, Tuhin S. Roy, Francisco X. Yumiceva, Cms Collaboration

Aerospace, Physics, and Space Science Faculty Publications

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 13TeV. The analysed data sample, recorded with the CMS detector at the CERN LHC, corresponds to an integrated luminosity of 2.3fb-1. Several kinematic variables are employed to suppress the dominant background, multijet production, as well as to discriminate between other standard model and new physics processes. The search provides sensitivity to a broad range of new-physics models that yield a stable weakly interacting massive particle. The number of observed candidate events …


Search For Single Production Of Vector-Like Quarks Decaying To A Z Boson And A Top Or A Bottom Quark In Proton-Proton Collisions At √S=13 Tev, M M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, D Noonan, Tuhin S. Roy, Francisco X. Yumiceva, Cms Collaboration May 2017

Search For Single Production Of Vector-Like Quarks Decaying To A Z Boson And A Top Or A Bottom Quark In Proton-Proton Collisions At √S=13 Tev, M M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, D Noonan, Tuhin S. Roy, Francisco X. Yumiceva, Cms Collaboration

Aerospace, Physics, and Space Science Faculty Publications

A search for single production of vector-like quarks, T and B, decaying into a Z boson and a top or a bottom quark, respectively, is presented. The search is performed using data collected by the CMS experiment at the LHC in proton-proton collisions at s=13 TeV, corresponding to an integrated luminosity of 2.3fb−1. An exotic T quark production mode through the decay of a heavy Z′ resonance is also considered. The search is performed in events with a Z boson decaying leptonically, accompanied by a bottom or a top quark decaying hadronically. No excess of events is observed over the …


Observation Of Y(1s) Pair Production In Proton-Proton Collisions At √S=8 Tev, M M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, D Noonan, Tuhin S. Roy, Francisco X. Yumiceva, Cms Collaboration May 2017

Observation Of Y(1s) Pair Production In Proton-Proton Collisions At √S=8 Tev, M M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, D Noonan, Tuhin S. Roy, Francisco X. Yumiceva, Cms Collaboration

Aerospace, Physics, and Space Science Faculty Publications

Pair production of Y(1S) mesons is observed at the LHC in proton-proton collisions at 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 smaller than 2.0. The fiducial cross section for the production of Y(1S) pairs, assuming that both mesons decay isotropically, is measured to be 68.8±12.7 (stat)±7.4 (syst)±2.8 (ℬ) pb, where the third uncertainty comes from the uncertainty in the branching fraction of Y(1S) decays to μ+μ−. Assuming …


Measurement Of Differential Cross Sections For Top Quark Pair Production Using The Lepton + Jets Final State In Proton-Proton Collisions At 13 Tev, A. M. Sirunyan, V. Khachatryan, A. R. Tumasyan, Marc M. Baarmand, Marcus Hohlmann, Vallary Bhopatkar, Stefano Colafranceschi, Daniel Noonan, Tuhin S. Roy, Francisco X. Yumiceva May 2017

Measurement Of Differential Cross Sections For Top Quark Pair Production Using The Lepton + Jets Final State In Proton-Proton Collisions At 13 Tev, A. M. Sirunyan, V. Khachatryan, A. R. Tumasyan, Marc M. Baarmand, Marcus Hohlmann, Vallary Bhopatkar, Stefano Colafranceschi, Daniel Noonan, Tuhin S. Roy, Francisco X. Yumiceva

Aerospace, Physics, and Space Science Faculty Publications

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 integrated luminosity of 2.3 fb-1. The measurements are performed in the lepton+jets decay channels with a single muon or electron in the final state. The differential cross sections are presented at particle level, within a phase space close to the experimental acceptance, and at …


Measurement Of Prompt And Nonprompt J / Ψ Production In P P And P Pb Collisions At √Snn=5.02tev, M M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, D Noonan, Tuhin S. Roy, Francisco X. Yumiceva, Cms Collaboration Apr 2017

Measurement Of Prompt And Nonprompt J / Ψ Production In P P And P Pb Collisions At √Snn=5.02tev, M M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, D Noonan, Tuhin S. Roy, Francisco X. Yumiceva, Cms Collaboration

Aerospace, Physics, and Space Science Faculty Publications

This paper reports the measurement of J / ψ meson production in proton–proton (p p) and proton–lead (p Pb) collisions at a center-of-mass energy per nucleon pair of 5.02TeV by the CMS experiment at the LHC. The data samples used in the analysis correspond to integrated luminosities of 28pb-1 and 35nb-1 for p p and p Pb collisions, respectively. Prompt and nonprompt J / ψ mesons, the latter produced in the decay of B hadrons, are measured in their dimuon decay channels. Differential cross sections are measured in the transverse momentum range of 2


Search For Electroweak Production Of A Vector-Like Quark Decaying To A Top Quark And A Higgs Boson Using Boosted Topologies In Fully Hadronic Final States, M M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, D Noonan, Tuhin S. Roy, Francisco X. Yumiceva, Cms Collaboration Apr 2017

Search For Electroweak Production Of A Vector-Like Quark Decaying To A Top Quark And A Higgs Boson Using Boosted Topologies In Fully Hadronic Final States, M M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, D Noonan, Tuhin S. Roy, Francisco X. Yumiceva, Cms Collaboration

Aerospace, Physics, and Space Science Faculty Publications

A search is performed for electroweak production of a vector-like top quark partner T of charge 2/3 in association with a standard model top or bottom quark, using 2.3 fb−1 of proton-proton collision data at s=13 TeV collected by the CMS experiment at the CERN LHC. The search targets T quarks decaying to a top quark and a Higgs boson in fully hadronic final states. For a T quark with mass above 1 TeV the daughter top quark and Higgs boson are highly Lorentz-boosted and can each appear as a single hadronic jet. Jet substructure and b tagging techniques are …


Suppression And Azimuthal Anisotropy Of Prompt And Nonprompt J / Ψ Production In Pbpb Collisions At √Snn=2.76tev, M M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, D Noonan, Tuhin S. Roy, Francisco X. Yumiceva, Cms Collaboration Apr 2017

Suppression And Azimuthal Anisotropy Of Prompt And Nonprompt J / Ψ Production In Pbpb Collisions At √Snn=2.76tev, M M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, D Noonan, Tuhin S. Roy, Francisco X. Yumiceva, Cms Collaboration

Aerospace, Physics, and Space Science Faculty Publications

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=2.76TeV at the LHC, are reported. The results are presented in several event centrality intervals and several kinematic regions, for transverse momenta pT> 6.5 GeV/c and rapidity | y| < 2.4 , extending down to pT= 3 GeV/c in the 1.6 < | y| < 2.4 range. The v2 of prompt J / ψ is found to be nonzero, but with no strong dependence on centrality, rapidity, or pT over the full kinematic range studied. The measured v2 of nonprompt J / ψ is consistent with zero. The RAA of prompt J / ψ exhibits a suppression that increases from peripheral to central collisions but does not vary strongly as a function of either y or pT in the fiducial range. The nonprompt J / ψRAA shows a suppression which becomes stronger as rapidity or pT increases. The v2 and RAA of open and hidden charm, and of open charm and beauty, are compared.


Measurement Of The Wz Production Cross Section In Pp Collisions At √S=7 And 8 Tev And Search For Anomalous Triple Gauge Couplings At √S=8tev, M M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, D Noonan, Tuhin S. Roy, Francisco X. Yumiceva, Cms Collaboration Apr 2017

Measurement Of The Wz Production Cross Section In Pp Collisions At √S=7 And 8 Tev And Search For Anomalous Triple Gauge Couplings At √S=8tev, M M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, D Noonan, Tuhin S. Roy, Francisco X. Yumiceva, Cms Collaboration

Aerospace, Physics, and Space Science Faculty Publications

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 4.9fb-1 collected at s=7TeV, and 19.6fb-1 at s=8TeV. The measurements are performed using the fully-leptonic WZ decay modes with electrons and muons in the final state. The measured cross sections for 71


Charged-Particle Nuclear Modification Factors In Pbpb And Ppb Collisions At √Snn=5.02 Tev, M M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, D Noonan, Tuhin S. Roy, Francisco X. Yumiceva, Cms Collaboration Apr 2017

Charged-Particle Nuclear Modification Factors In Pbpb And Ppb Collisions At √Snn=5.02 Tev, M M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, D Noonan, Tuhin S. Roy, Francisco X. Yumiceva, Cms Collaboration

Aerospace, Physics, and Space Science Faculty Publications

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 collisions. The corresponding nuclear modification factor, RAA, is measured in bins of collision centrality. The RAA in the 5% most central collisions shows a maximal suppression by a factor of 7-8 in the pT region of 6-9 GeV. This dip is followed by an increase, which continues up to the highest pT measured, and approaches unity in the vicinity of pT = 200 GeV. The RAA is compared to theoretical predictions and earlier experimental results at lower collision energies. The newly measured pp spectrum is combined with the pPb spectrum previously published by the CMS collaboration to construct the pPb nuclear modification factor, RpA, up to 120 GeV. For pT> 20 GeV, RpA exhibits weak momentum dependence and shows a moderate enhancement above unity.


Measurements Of Differential Production Cross Sections For A Z Boson In Association With Jets In Pp Collisions At √S=8 Tev, M M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, D Noonan, Tuhin S. Roy, Francisco X. Yumiceva, Cms Collaboration Apr 2017

Measurements Of Differential Production Cross Sections For A Z Boson In Association With Jets In Pp Collisions At √S=8 Tev, M M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, D Noonan, Tuhin S. Roy, Francisco X. Yumiceva, Cms Collaboration

Aerospace, Physics, and Space Science Faculty Publications

Cross sections for the production of a Z boson in association with jets in proton-proton collisions at a centre-of-mass energy of 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 the jet kinematics and the jet activity. Correlations between the azimuthal directions and the rapidities of the jets and the Z boson are studied in detail. The predictions of a number of multileg generators with leading or next-to-leading order accuracy are compared with the measurements. …


Search For Massive Resonances Decaying Into Ww, Wz Or Zz Bosons In Proton-Proton Collisions At √S=13 Tev, M M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, D Noonan, Tuhin S. Roy, Francisco X. Yumiceva, Cms Collaboration Mar 2017

Search For Massive Resonances Decaying Into Ww, Wz Or Zz Bosons In Proton-Proton Collisions At √S=13 Tev, M M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, D Noonan, Tuhin S. Roy, Francisco X. Yumiceva, Cms Collaboration

Aerospace, Physics, and Space Science Faculty Publications

A search is presented for new massive resonances decaying to WW, WZ or ZZ bosons in ℓνqq¯ and qq¯ qq¯ final states. Results are based on data corresponding to an integrated luminosity of 2.3-2.7 fb−1 recorded in proton-proton collisions at s=13 TeV with the CMS detector at the LHC. Decays of spin-1 and spin-2 resonances into two vector bosons are sought in the mass range 0.6-4.0 TeV. No significant excess over the standard model background is observed. Combining the results of the ℓνqq¯ and qq¯ qq¯ final states, cross section and mass exclusion limits are set for models that predict …


Measurement And Qcd Analysis Of Double-Differential Inclusive Jet Cross Sections In Pp Collisions At √S=8 Tev And Cross Section Ratios To 2.76 And 7 Tev, M M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, D Noonan, Tuhin S. Roy, Francisco X. Yumiceva, Cms Collaboration Mar 2017

Measurement And Qcd Analysis Of Double-Differential Inclusive Jet Cross Sections In Pp Collisions At √S=8 Tev And Cross Section Ratios To 2.76 And 7 Tev, M M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, D Noonan, Tuhin S. Roy, Francisco X. Yumiceva, Cms Collaboration

Aerospace, Physics, and Space Science Faculty Publications

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 the anti-kT clustering algorithm with a size parameter of 0.7 in a phase space region covering jet pT from 74 GeV up to 2.5 TeV and jet absolute rapidity up to |y| = 3.0. The low-pT jet range between 21 and 74 GeV is also studied up …


Search For Cp Violation In Tt¯ Production And Decay In Proton-Proton Collisions At √S=8 Tev, M M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, D Noonan, Tuhin S. Roy, Francisco X. Yumiceva, Cms Collaboration Mar 2017

Search For Cp Violation In Tt¯ Production And Decay In Proton-Proton Collisions At √S=8 Tev, M M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, D Noonan, Tuhin S. Roy, Francisco X. Yumiceva, Cms Collaboration

Aerospace, Physics, and Space Science Faculty Publications

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, corresponding to an integrated luminosity of 19.7 fb−1. Events are selected having one electron or muon and at least four jets. The T-odd observables are measured using four-momentum vectors associated with tt¯ production and decay. The measured asymmetries exhibit no evidence for CP-violating effects, consistent with …


Measurement Of The T T ¯ Production Cross Section Using Events In The E Μ Final State In Pp Collisions At √S=13 Tev, M M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, D Noonan, Tuhin S. Roy, Francisco X. Yumiceva, Cms Collaboration Mar 2017

Measurement Of The T T ¯ Production Cross Section Using Events In The E Μ Final State In Pp Collisions At √S=13 Tev, M M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, D Noonan, Tuhin S. Roy, Francisco X. Yumiceva, Cms Collaboration

Aerospace, Physics, and Space Science Faculty Publications

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 electron, one muon, and two or more jets, at least one of which is identified as originating from hadronization of a b quark. The measured cross section is 815±9(stat)±38(syst)±19(lumi) pb, in agreement with the expectation from the standard model.


Search For Heavy Neutrinos Or Third-Generation Leptoquarks In Final States With Two Hadronically Decaying Τ Leptons And Two Jets In Proton-Proton Collisions At √S=13 Tev, M M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, D Noonan, Tuhin S. Roy, Francisco X. Yumiceva, Cms Collaboration Mar 2017

Search For Heavy Neutrinos Or Third-Generation Leptoquarks In Final States With Two Hadronically Decaying Τ Leptons And Two Jets In Proton-Proton Collisions At √S=13 Tev, M M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, D Noonan, Tuhin S. Roy, Francisco X. Yumiceva, Cms Collaboration

Aerospace, Physics, and Space Science Faculty Publications

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, corresponding to an integrated luminosity of 2.1 fb−1. The results are interpreted in two physics models. The first model involves heavy right-handed neutrinos, Nℓ (ℓ = e, μ, τ), and right-handed charged bosons, WR, arising in a left-right symmetric extension of the standard model. Masses of …


Search For Dark Matter And Unparticles In Events With A Z Boson And Missing Transverse Momentum In Proton-Proton Collisions At √S=13 Tev, M M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, D Noonan, Tuhin S. Noonan, Francisco X. Yumiceva, Cms Collaboration Mar 2017

Search For Dark Matter And Unparticles In Events With A Z Boson And Missing Transverse Momentum In Proton-Proton Collisions At √S=13 Tev, M M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, D Noonan, Tuhin S. Noonan, Francisco X. Yumiceva, Cms Collaboration

Aerospace, Physics, and Space Science Faculty Publications

A search for dark matter and unparticle production at the LHC has been performed using events containing two charged leptons (electrons or muons), consistent with the decay of a Z boson, and large missing transverse momentum. This study is based on data collected with the CMS detector in 2015, corresponding to an integrated luminosity of 2.3 fb−1 of proton-proton collisions at the LHC, at a center-of-mass energy of 13 TeV. No excess over the standard model expectation is observed. Compared to previous searches in this topology, which exclusively relied on effective field theories, the results are interpreted in terms of …


Measurement Of The Transverse Momentum Spectrum Of The Higgs Boson Produced In Pp Collisions At √S=8 Tev Using H → Ww Decays, M M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, D Noonan, Tuhin S. Roy, Francisco X. Yumiceva, Cms Collaboration Mar 2017

Measurement Of The Transverse Momentum Spectrum Of The Higgs Boson Produced In Pp Collisions At √S=8 Tev Using H → Ww Decays, M M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, D Noonan, Tuhin S. Roy, Francisco X. Yumiceva, Cms Collaboration

Aerospace, Physics, and Space Science Faculty Publications

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 an integrated luminosity of 19.4 fb−1. The Higgs boson transverse momentum (pT) is reconstructed using the lepton pair pT and missing pT. The differential cross section times branching fraction is measured as a function of the Higgs boson pT in …


Searches For Invisible Decays Of The Higgs Boson In Pp Collisions At √S = 7, 8, And 13 Tev, M M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, D Noonan, Tuhin S. Roy, Francisco X. Yumiceva, Cms Collaboration Feb 2017

Searches For Invisible Decays Of The Higgs Boson In Pp Collisions At √S = 7, 8, And 13 Tev, M M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, D Noonan, Tuhin S. Roy, Francisco X. Yumiceva, Cms Collaboration

Aerospace, Physics, and Space Science Faculty Publications

Searches for invisible decays of the Higgs boson are presented. The data collected with the CMS detector at the LHC correspond to integrated luminosities of 5.1, 19.7, and 2.3 fb−1 at centre-of-mass energies of 7, 8, and 13 TeV, respectively. The search channels target Higgs boson production via gluon fusion, vector boson fusion, and in association with a vector boson. Upper limits are placed on the branching fraction of the Higgs boson decay to invisible particles, as a function of the assumed production cross sections. The combination of all channels, assuming standard model production, yields an observed (expected) upper limit …


Measurement Of The Transverse Momentum Spectra Of Weak Vector Bosons Produced In Proton-Proton Collisions At √S=8 Tev, M M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, H Kalakhety, D Noonan, Tuhin S. Roy, Francisco X. Yumiceva, Cms Collaboration Feb 2017

Measurement Of The Transverse Momentum Spectra Of Weak Vector Bosons Produced In Proton-Proton Collisions At √S=8 Tev, M M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, H Kalakhety, D Noonan, Tuhin S. Roy, Francisco X. Yumiceva, Cms Collaboration

Aerospace, Physics, and Space Science Faculty Publications

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 muon decay modes, while the production of Z bosons is studied using only the dimuon decay channel. The ratios of W− to W+ and Z to W differential cross sections are also measured. The measured differential cross sections and ratios are compared with theoretical …


Search For Top Quark Decays Via Higgs-Boson-Mediated Flavor-Changing Neutral Currents In Pp Collisions At √S=8 Tev, M M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, D Noonan, Tuhin S. Roy, Francisco X. Yumiceva, Cms Collaboration Feb 2017

Search For Top Quark Decays Via Higgs-Boson-Mediated Flavor-Changing Neutral Currents In Pp Collisions At √S=8 Tev, M M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, D Noonan, Tuhin S. Roy, Francisco X. Yumiceva, Cms Collaboration

Aerospace, Physics, and Space Science Faculty Publications

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 one top quark decaying into a charm or up quark and a Higgs boson (H), and the other top quark decaying into a bottom quark and a W boson are selected. The Higgs boson in these events is assumed to subsequently decay into either …


Measurement Of The Production Cross Section Of A W Boson In Association With Two B Jets In Pp Collisions At √S=8tev, M M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, D Noonan, Tuhin S. Roy, Francisco X. Yumiceva, Cms Collaboration Feb 2017

Measurement Of The Production Cross Section Of A W Boson In Association With Two B Jets In Pp Collisions At √S=8tev, M M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, D Noonan, Tuhin S. Roy, Francisco X. Yumiceva, Cms Collaboration

Aerospace, Physics, and Space Science Faculty Publications

The production cross section of a W boson in association with two b jets is measured using a sample of proton–proton collisions at s=8TeV collected by the CMS experiment at the CERN LHC. The data sample corresponds to an integrated luminosity of 19.8fb-1. The W bosons are reconstructed via their leptonic decays, W → ℓν, where ℓ= μ or e. The fiducial region studied contains exactly one lepton with transverse momentum pTℓ>30GeV and pseudorapidity | ηℓ| < 2.1 , with exactly two b jets with pT>25GeV and | η| < 2.4 and no other jets with pT>25GeV and | η| < 4.7. The cross section is measured to be σ(p p → W (ℓν) +bb¯)=0.64±0.03(stat)±0.10(syst)±0.06(theo)±0.02(lumi)pb, in agreement with standard model predictions.


Search For Heavy Resonances Decaying To Tau Lepton Pairs In Proton-Proton Collisions At √S=13 Tev, M M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, D Noonan, Tuhin S. Roy, Francisco X. Yumiceva, Cms Collaboration Feb 2017

Search For Heavy Resonances Decaying To Tau Lepton Pairs In Proton-Proton Collisions At √S=13 Tev, M M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, D Noonan, Tuhin S. Roy, Francisco X. Yumiceva, Cms Collaboration

Aerospace, Physics, and Space Science Faculty Publications

A search for heavy resonances that decay to tau lepton pairs is performed using proton-proton collisions at s=13 TeV. 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 the product of the production cross section and branching fraction into tau lepton pairs is calculated as a function of the resonance mass. For the sequential standard model, the presence of Z′ bosons decaying into tau lepton pairs is excluded for Z′ masses …


Search For Anomalous Wtb Couplings And Flavour-Changing Neutral Currents In T-Channel Single Top Quark Production In Pp Collisions At √S=7 And 8 Tev, M M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, D Noonan, Tuhin S. Roy, Francisco X. Yumiceva, Cms Collaboration Feb 2017

Search For Anomalous Wtb Couplings And Flavour-Changing Neutral Currents In T-Channel Single Top Quark Production In Pp Collisions At √S=7 And 8 Tev, M M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, D Noonan, Tuhin S. Roy, Francisco X. Yumiceva, Cms Collaboration

Aerospace, Physics, and Space Science Faculty Publications

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, respectively. The analysis is performed using events with one muon and two or three jets. A Bayesian neural network technique is used to discriminate between the signal and backgrounds, which are observed to be consistent with the standard model prediction. The 95% confidence level …


Search For Supersymmetry In Events With One Lepton And Multiple Jets In Proton-Proton Collisions At Square Root Of S = 13 Tev, V. Khachatryan, A. M. Sirunyan, A. R. Tumasyan, Marc M. Baarmand, Vallary Bhopatkar, Marcus Hohlmann, Daniel Noonan, Stefano Colafranceschi, Tuhin S. Roy, Francisco X. Yumiceva Jan 2017

Search For Supersymmetry In Events With One Lepton And Multiple Jets In Proton-Proton Collisions At Square Root Of S = 13 Tev, V. Khachatryan, A. M. Sirunyan, A. R. Tumasyan, Marc M. Baarmand, Vallary Bhopatkar, Marcus Hohlmann, Daniel Noonan, Stefano Colafranceschi, Tuhin S. Roy, Francisco X. Yumiceva

Aerospace, Physics, and Space Science Faculty Publications

A search for supersymmetry is performed in events with a single electron or muon in proton-proton collisions at a center-of-mass energy of 13 TeV. The data were recorded by the CMS experiment at the LHC and correspond to an integrated luminosity of 2.3 fb-1. Several exclusive search regions are defined based on the number of jets and b-tagged jets, the scalar sum of the jet transverse momenta, and the scalar sum of the missing transverse momentum and the transverse momentum of the lepton. The observed event yields in data are consistent with the expected backgrounds from standard model processes. The …