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Sirunyan, A. M.,Tumasyan, A.,Adam, W.,Ambrogi, F.,Asilar, E.,Bergauer, T.,Brandstetter, J.,Brondolin, E.,Dragicevic, M.,Erö,, J.,Escalante Del Valle, A.,Flechl, M.,Friedl, M.,Frü,hwirth, R.,Gh Institute of Physics Pub 2018 The journal of high energy physics Vol.2018 No.5
<P>A search for a heavy right-handed W boson (W-R) decaying to a heavy right-handed neutrino and a charged lepton in events with two same-flavor leptons (e or mu) and two jets, is presented. The analysis is based on proton-proton collision data, collected by the CMS Collaboration at the LHC in 2016 and corresponding to an integrated luminosity of 35.9 fb(-1). No significant excess above the standard model expectation is seen in the invariant mass distribution of the dilepton plus dijet system. Assuming that couplings are identical to those of the standard model, and that only one heavy neutrino flavor N-R contributes significantly to the W-R decay width, the region in the two-dimensional (m(WR), m(NR)) mass plane excluded at 95% confidence level extends to approximately m(WR) = 4 : 4TeV and covers a large range of right-handed neutrino masses below the W-R boson mass. This analysis provides the most stringent limits on the W-R mass to date.</P>
Sirunyan, A. M.,Tumasyan, A.,Adam, W.,Ambrogi, F.,Asilar, E.,Bergauer, T.,Brandstetter, J.,Brondolin, E.,Dragicevic, M.,Erö,, J.,Escalante Del Valle, A.,Flechl, M.,Frü,hwirth, R.,Ghete, V. M. Springer-Verlag 2018 Journal of high energy physics Vol.2018 No.8
<P>A search is presented for long-lived charged particles that decay within the CMS detector and produce the signature of a disappearing track. A disappearing track is an isolated track with missing hits in the outer layers of the silicon tracker, little or no energy in associated calorimeter deposits, and no associated hits in the muon detectors. This search uses data collected with the CMS detector in 2015 and 2016 from proton-proton collisions at a center-of-mass energy of 13 TeV at the LHC, corresponding to an integrated luminosity of 38.4 fb(-1). The results of the search are interpreted in the context of the anomaly-mediated supersymmetry breaking model. The data are consistent with the background-only hypothesis. Limits are set on the product of the cross section for direct production of charginos and their branching fraction to a neutralino and a pion, as a function of the chargino mass and lifetime. At 95% confidence level, charginos with masses below 715 (695) GeV are excluded for a lifetime of 3 (7) ns, as are charginos with lifetimes from 0.5 to 60 ns for a mass of 505 GeV. These are the most stringent limits using a disappearing track signature on this signal model for chargino lifetimes above approximate to 0.7 ns.</P>
Sirunyan, A. M.,Tumasyan, A.,Adam, W.,Ambrogi, F.,Asilar, E.,Bergauer, T.,Brandstetter, J.,Brondolin, E.,Dragicevic, M.,Erö,, J.,Escalante Del Valle, A.,Flechl, M.,Friedl, M.,Frü,hwirth, R.,Gh Springer-Verlag 2018 Journal of high energy physics Vol.2018 No.9
<P>A search has been performed for heavy resonances decaying to ZZ or ZW in 2l2q final states, with two charged leptons (l = e, mu) produced by the decay of a Z boson, and two quarks produced by the decay of a W or Z boson. The analysis is sensitive to resonances with masses in the range from 400 to 4500 GeV. Two categories are defined based on the merged or resolved reconstruction of the hadronically decaying vector boson, optimized for high- and low-mass resonances, respectively. The search is based on data collected during 2016 by the CMS experiment at the LHC in proton-proton collisions with a center-of-mass energy of root s = 13 TeV, corresponding to an integrated luminosity of 35.9 fb(-1). No excess is observed in the data above the standard model background expectation. Upper limits on the production cross section of heavy, narrow spin-1 and spin-2 resonances are derived as a function of the resonance mass, and exclusion limits on the production of W' bosons and bulk graviton particles are calculated in the framework of the heavy vector triplet model and warped extra dimensions, respectively.</P>
Observation of the χb1(3P) and χb2(3P) and Measurement of their Masses
Sirunyan, A. M.,Tumasyan, A.,Adam, W.,Ambrogi, F.,Asilar, E.,Bergauer, T.,Brandstetter, J.,Dragicevic, M.,Erö,, J.,Escalante Del Valle, A.,Flechl, M.,Frü,hwirth, R.,Ghete, V. M.,Hrubec, J.,Jei American Physical Society 2018 Physical Review Letters Vol.121 No.9
<P>The chi(b1)(3P) and chi(b2)(3P) states are observed through their gamma(3S)(gamma) decays, using an event sample of proton-proton collisions collected by the CMS experiment at the CERN LHC. The data were collected at a center-of-mass energy of 13 TeV and correspond to an integrated luminosity of 80.0 fb(-1). The gamma(3S) mesons are identified through their dimuon decay channel, while the low-energy photons are detected after converting to e(+)e(-) pairs in the silicon tracker, leading to a chi(b)(3P) mass resolution of 2.2 MeV. This is the first time that the J = 1 and 2 states are well resolved and their masses individually measured: 10513.42 +/- 0.41(stat) +/- 0.18(syst) MeV and 10524.02 +/- 0.57(stat) +/- 0.18(syst) MeV; they are determined with respect to the world-average value of gamma(3S) mass, which has an uncertainty of 0.5 MeV. The mass splitting is measured to be 10.60 +/- 0.64(stat) +/- 0.17(syst) MeV.</P>
Sirunyan, A. M.,Tumasyan, A.,Adam, W.,Ambrogi, F.,Asilar, E.,Bergauer, T.,Brandstetter, J.,Brondolin, E.,Dragicevic, M.,Erö,, J.,Escalante Del Valle, A.,Flechl, M.,Friedl, M.,Frü,hwirth, R.,Gh American Physical Society 2018 Physical Review Letters Vol.120 No.24
<P>A search for physics beyond the standard model in events with one or more high-momentum Higgs bosons, H, decaying to pairs of b quarks in association with missing transverse momentum is presented. The data, corresponding to an integrated luminosity of 35.9 fb(-1), were collected with the CMS detector at the LHC in proton-proton collisions at the center-of-mass energy root s = 13 TeV. The analysis utilizes a new b quark tagging technique based on jet substructure to identify jets from H -> b (b) over bar. Events are categorized by the multiplicity of H-tagged jets, jet mass, and the missing transverse momentum. No significant deviation from standard model expectations is observed. In the context of supersymmetry (SUSY), limits on the cross sections of pair-produced gluinos are set, assuming that gluinos decay to quark pairs, H (or Z), and the lightest SUSY particle, LSP, through an intermediate next-to-lightest SUSY particle, NLSP. With large mass splitting between the NLSP and LSP, and 100% NLSP branching fraction to H, the lower limit on the gluino mass is found to be 2010 GeV.</P>
Search for single production of vector-like quarks decaying to a b quark and a Higgs boson
Sirunyan, A. M.,Tumasyan, A.,Adam, W.,Ambrogi, F.,Asilar, E.,Bergauer, T.,Brandstetter, J.,Brondolin, E.,Dragicevic, M.,Erö,, J.,Escalante Del Valle, A.,Flechl, M.,Friedl, M.,Frü,hwirth, R.,Gh Springer-Verlag 2018 Journal of high energy physics Vol.2018 No.6
<P>A search is presented for single production of heavy vector-like quarks (B) that decay to a Higgs boson and a b quark, with the Higgs boson decaying to a highly boosted b (b) over bar pair reconstructed as a single collimated jet. The analysis is based on data collected by the CMS experiment in proton-proton collisions at root s = 13 TeV, corresponding to an integrated luminosity of 35.9 fb(-1). The data are consistent with background expectations, and upper limits at 95% confidence level on the product of the B quark cross section and the branching fraction are obtained in the range 1.28-0.07 pb, for a narrow B quark with a mass between 700 and 1800 GeV. The production of B quarks with widths of 10, 20 and 30% of the resonance mass is also considered, and the sensitivities obtained are similar to those achieved in the narrow width case. This is the first search at the CERN LHC for the single production of a B quark through its fully hadronic decay channel, and the first study considering finite resonance widths of the B quark.</P>
Sirunyan, A. M.,Tumasyan, A.,Adam, W.,Ambrogi, F.,Asilar, E.,Bergauer, T.,Brandstetter, J.,Brondolin, E.,Dragicevic, M.,Erö,, J.,Escalante Del Valle, A.,Flechl, M.,Friedl, M.,Frü,hwirth, R.,Gh Institute of Physics Pub 2018 The journal of high energy physics Vol.2018 No.4
<P>A search is reported for heavy resonances decaying into e mu final states in proton-proton collisions recorded by the CMS experiment at the CERN LHC at root s = 13 TeV, corresponding to an integrated luminosity of 35.9 fb(-1). The search focuses on resonance masses above 200 GeV. With no evidence found for physics beyond the standard model in the e mu mass spectrum, upper limits are set at 95% confidence level on the product of the cross section and branching fraction for this lepton-flavor violating signal. Based on these results, resonant tau sneutrino production in R-parity violating supersymmetric models is excluded for masses below 1.7 TeV, for couplings lambda(132) = lambda(231) = lambda(311) = 0.01. Heavy Z' gauge bosons with lepton-flavor violating transitions are excluded for masses up to 4.4 TeV. The eit mass spectrum is also interpreted in terms of non-resonant contributions from quantum black-hole production in models with one to six extra spatial dimensions, and lower mass limits are found between 3.6 and 5.6 TeV. In all interpretations used in this analysis, the results of this search improve previous limits by about 1 TeV. These limits correspond to the most sensitive values obtained at colliders.</P>
Sirunyan, A. M.,Tumasyan, A.,Adam, W.,Ambrogi, F.,Asilar, E.,Bergauer, T.,Brandstetter, J.,Brondolin, E.,Dragicevic, M.,Erö,, J.,Escalante Del Valle, A.,Flechl, M.,Frü,hwirth, R.,Ghete, V. M. Institute of Physics Pub 2018 The journal of high energy physics Vol.2018 No.8
<P>A search is presented for pair production of heavy vector-like T and B quarks in proton-proton collisions at A root s = 13 TeV. The data sample corresponds to an integrated luminosity of 35.9 fb(-1), collected with the CMS detector at the CERN LHC in 2016. Pair production of T quarks would result in a wide range of final states, since vector-like T quarks of charge 2e/3 are predicted to decay to bW, tZ, and tH. Likewise, vector-like B quarks are predicted to decay to tW, bZ, and bH. Three channels are considered, corresponding to final states with a single lepton, two leptons with the same sign of the electric charge, or at least three leptons. The results exclude T quarks with masses below 1140-1300 GeV and B quarks with masses below 910-1240 GeV for various branching fraction combinations, extending the reach of previous CMS searches by 200-600 GeV.</P>
Sirunyan, A. M.,Tumasyan, A.,Adam, W.,Ambrogi, F.,Asilar, E.,Bergauer, T.,Brandstetter, J.,Brondolin, E.,Dragicevic, M.,Erö,, J.,Escalante Del Valle, A.,Flechl, M.,Friedl, M.,Frü,hwirth, R.,Gh Institute of Physics Pub 2018 The journal of high energy physics Vol.2018 No.7
<P>A search is presented for a heavy resonance decaying into either a pair of Z bosons or a Z boson and a W boson (ZZ or WZ), with a Z boson decaying into a pair of neutrinos and the other boson decaying hadronically into two collimated quarks that are reconstructed as a highly energetic large-cone jet. The search is performed using the data collected with the CMS detector at the CERN LHC during 2016 in proton-proton collisions at a center-of-mass energy of 13 TeV, corresponding to a total integrated luminosity of 35.9 fb(-1). No excess is observed in data with regard to background expectations. Results are interpreted in scenarios of physics beyond the standard model. Limits at 95% confidence level on production cross sections are set at 0.9 fb (63 fb) for spin-1 W' bosons, included in the heavy vector triplet model, with mass 4.0 TeV (1.0 TeV), and at 0.5 fb (40 fb) for spin-2 bulk gravitons with mass 4.0 TeV (1.0 TeV). Lower limits are set on the masses of W' bosons in the context of two versions of the heavy vector triplet model of 3.1 TeV and 3.4 TeV, respectively.</P>
Sirunyan, A. M.,Tumasyan, A.,Adam, W.,Ambrogi, F.,Asilar, E.,Bergauer, T.,Brandstetter, J.,Brondolin, E.,Dragicevic, M.,Erö,, J.,Escalante Del Valle, A.,Flechl, M.,Friedl, M.,Frü,hwirth, R.,Gh Institute of Physics Pub 2018 The journal of high energy physics Vol.2018 No.6
<P>Measurements of differential t (t) over bar production cross sections are presented in the single-lepton decay channel, as a function of a number of kinematic event variables. The measurements are performed with proton-proton collision data at root s = 13 TeV, collected by the CMS experiment at the LHC during 2016, with an integrated luminosity of 35.9 fb(-1). The data are compared to a variety of state-of-the-art leading-order and next-to-leading order t (t) over bar simulations.</P>