A search for supersymmetry with R-parity conservation in proton-proton collisions at a centre-of-mass energy of 7 TeV is presented. The data correspond to an integrated luminosity of 35 inverse picobarns collected by the CMS experiment at the LHC. The search is performed in events with jets and significant missing transverse energy, characteristic of the decays of heavy, pair-produced squarks and gluinos. The primary background, from standard model multijet production, is reduced by several orders of magnitude to a negligible level by the application of a set of robust kinematic requirements. With this selection, the data are consistent with the standard model backgrounds, namely t t-bar, W + jet and Z + jet production, which are estimated from data control samples. Limits are set on the parameters of the constrained minimal supersymmetric extension of the standard model. These limits extend those set previously by experiments at the Tevatron and LEP colliders

A search for neutral Higgs bosons in the minimal supersymmetric extension of the standard model (MSSM) decaying to tau-lepton pairs in pp collisions is performed, using events recorded by the CMS experiment at the LHC. The dataset corresponds to an integrated luminosity of 24.6 fb −1 , with 4.9 fb −1 at 7 TeV and 19.7 fb −1 at 8 TeV. To enhance the sensitivity to neutral MSSM Higgs bosons, the search includes the case where the Higgs boson is produced in association with a b-quark jet. No excess is observed in the tau-lepton-pair invariant mass spectrum. Exclusion limits are presented in the MSSM parameter space for different benchmark scenarios, m max h , m mod+ h , m mod− h , light-stop, lightstau, τ -phobic, and low-m H . Upper limits on the cross section times branching fraction for gluon fusion and b-quark associated Higgs boson production are also given. A Exclusion limits 23The CMS collaboration 37 IntroductionA broad variety of precision measurements have shown the overwhelming success of the standard model (SM) [1][2][3] of fundamental interactions, which includes an explanation for the origin of the mass of the weak force carriers, as well as for the quark and lepton masses. In the SM, this is achieved via the Brout-Englert-Higgs mechanism [4][5][6][7][8][9], which predicts the existence of a scalar boson, the Higgs boson. However, the Higgs boson mass in the SM is not protected against quadratically divergent quantum-loop corrections at high energy, known as the hierarchy problem. In the model of supersymmetry (SUSY) [10,11], which postulates a symmetry between the fundamental bosons and fermions, a cancellation of these divergences occurs naturally. The Higgs sector of the minimal supersymmetric extension of the standard model (MSSM) [12,13] The dominant neutral MSSM Higgs boson production mechanism is the gluon fusion process for small and moderate values of tan β. At large values of tan β b-quark associated production is the dominant contribution, due to the enhanced Higgs boson Yukawa coupling to b quarks. Figure 1 shows the leading-order diagrams for the gluon fusion and b-quark associated Higgs boson production, in the four-flavor and in the five-flavor scheme. In the region of large tan β the branching fraction to tau leptons is also enhanced, making the search for neutral MSSM Higgs bosons in the τ τ final state particularly interesting. This paper reports a search for neutral MSSM Higgs bosons in pp collisions at √ s = 7 TeV and 8 TeV in the τ τ decay channel. The data were recorded with the CMS detector [14] at the CERN LHC and correspond to an integrated luminosity of 24.6 fb −1 , with 4.9 fb −1 at 7 TeV and 19.7 fb −1 at 8 TeV. Five different τ τ signatures are studied, eτ h , µτ h , eµ, µµ, and τ h τ h , where τ h denotes a hadronically decaying τ . These results are an extension of previous searches by the The results are interpreted in the context of the MSSM with different benchmark scenarios described in section 1.1 and also in a model independent way, in terms of upper...

The results of comprehensive studies of missing transverse energy as measured by the CMS detector in pp collisions at a centre-of-mass energy of 7 TeV are presented. Three missing transverse energy reconstruction algorithms are deployed for various physics analyses. The scale and resolution for missing transverse energy are validated using vector boson and dijet events, and severe mismeasurements due to the detector are studied. We also parametrize the effects of multiple pp interactions within the same bunch crossings on the scale and resolution. A tool, called missing transverse energy significance, based on particle resolutions in each event is also presented.

Constraints on models of scalar and vector leptoquarks decaying to a quark and a neutrino at √ s = 13 TeVThe CMS Collaboration * AbstractThe results of a previous search by the CMS Collaboration for squarks and gluinos are reinterpreted to constrain models of leptoquark (LQ) production. The search considers jets in association with a transverse momentum imbalance, using the M T2 variable. The analysis uses proton-proton collision data at √ s = 13 TeV, recorded with the CMS detector at the LHC in 2016 and corresponding to an integrated luminosity of 35.9 fb −1 . Leptoquark pair production is considered with LQ decays to a neutrino and a top, bottom, or light quark. This reinterpretation considers higher mass values than the original CMS search to constrain both scalar and vector LQs. Limits on the cross section for LQ pair production are derived at the 95% confidence level depending on the LQ decay mode. A vector LQ decaying with a 50% branching fraction to tν, and 50% to bτ, has been proposed as part of an explanation of anomalous flavor physics results. In such a model, using only the decays to tν, LQ masses below 1530 GeV are excluded assuming the Yang-Mills case with coupling κ = 1, or 1115 GeV in the minimal coupling case κ = 0, placing the most stringent constraint to date from pair production of vector LQs.Published in Physical Review D as

A search for low mass narrow vector resonances decaying into quark-antiquark pairs is presented. The analysis is based on data collected in 2017 with the CMS detector at the LHC in proton-proton collisions at a center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 41.1 fb −1. The results of this analysis are combined with those of an earlier analysis based on data collected at the same collision energy in 2016, corresponding to 35.9 fb −1. Signal candidates will be recoiling against initial state radiation and are identified as energetic, large-radius jets with two pronged substructure. The invariant jet mass spectrum is probed for a potential narrow peaking signal over a smoothly falling background. No evidence for such resonances is observed within the mass range of 50-450 GeV. Upper limits at the 95% confidence level are set on the coupling of narrow resonances to quarks, as a function of the resonance mass. For masses between 50 and 300 GeV these are the most sensitive limits to date. This analysis extends the earlier search to a mass range of 300-450 GeV, which is probed for the first time with jet substructure techniques.