“…Two specific BSM models are excluded within certain mass ranges: the narrow leptophobic Z' boson with mass 600 - 1150 GeV and the wide Kaluza-Klein gluon with a mass below 1.5 TeV. …”
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“…The beams for the LHC are pre-accelerated in the SPS (Super Proton Synchrotron) to 450 GeV/c and trans- ferred to LHC via two beam lines. …”
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“…In July 2012, the discovery of a new neutral boson with a measured mass of about 126 GeV was announced by the ATLAS and CMS collaborations at the particle physics research laboratory CERN near Geneva. …”
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“…In this thesis, I present my work in the CMS experiment on a searchfor the standard model Higgs boson decaying into a pair of tau leptons.The original goal and the final aim of this research is a contribution to thediscovery of the Higgs boson at the LHC.After a summary of the theoretical framework and of the experimentalapparatus, I will describe the particle–flow technique developed for the offlineCMS event reconstruction, which I contributed to commission with the firstLHC collisions delivered at 900 GeV and 7 TeV center–of–mass energy. Theparticle–flow reconstruction gives optimal performances for the measurementof jets, missing transverse energy and taus, and is therefore ideally suited forthe search of the Higgs boson decaying to tau leptons.Tau reconstruction and identification in CMS are described. …”
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“…The cross-section was measured as a function of transverse momentum and rapidity of B+ mesons, extending recent measurements by the CMS and LHCb experiments at sqrt{s}=7 TeV to a higher transverse momentum region, up to about 100 GeV. The comparison of results with theoretical predictions of Quantum Chromodynamics is interesting in order to assess their validity at the new energy regime, especially after recent developments in the calculations that also showed good agreement with data from Tevatron. …”
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“…In total, 272 candidate $ZZ$ events are observed where both lepton pairs have an invariant mass in the range 66-116 GeV with an expected number of events from SM $ZZ$ of 227.3$\pm0.3$ and a background expectation of 10.3$\pm2.0$. …”
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“…The measured output distribution of the multivariate algorithm in each event category are compared with the expected signal and background distributions and an excess of events above the expected background is observed at a Higgs mass $m_H$ of 125GeV. The observed (expected) significance of this excess is 1.4$\sigma$ (2.6$\sigma$) and the ratio of the measured signal yield to the Standard Model expectation is found to be $\mu= 0.51 \pm 0.31(stat) \pm 0.24(syst)$. …”
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“…But when the antiprotons come to rest at the Bragg-peak, they annihilate, releasing almost 2 GeV per antiproton–proton annihilation. Most of this energy is carried away by energetic pions, but the Bragg-peak of the antiprotons is still locally augmented with ∼20–30 MeV per antiproton. …”
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“…The exclusion limits on the squark and gluino mass obtained from the reinterpretation extend up to 1200 GeV. These are the first results by any ATLAS SUSY search which systematically cover a wide range of RPV couplings in the case of prompt LSP decays. …”
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“…The statistical significance of this excess corresponds to 3.2 standard deviationsat a mass of 125 GeV. The measured signal strength is compatible with the SM Higgssignal expectation. …”
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“…Supersym- metric thermal leptogenesis with a hierarchical right-han ded neutrino mass spectrum normally requires the mass of the lightest right-handed neu trino to be heavier than about 10 9 GeV. This is in conflict with the upper bound on the reheating t empera- ture which is found by imposing that the gravitinos generate d during the reheating stage after inflation do not jeopardize successful nucleosy nthesis. …”
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“…Nearly $14\,000$ signal events, containing all possible intermediate resonances with a $K^+ \pi^- \pi^+$ final state in the $[1,2]\, \rm{GeV}/\it{c}^2$ mass interval, are reconstructed and selected in the data sample. …”
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“…Until now the experiment has achieved successful measurements for p+p collisions at sqrt(s) =900 GeV, 2.78 TeV, 7 TeV and 13 TeV and for p+Pb collision at sqrt(s_NN) = 5.0 TeV. …”
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“…For a Higgs Boson mass of 125 GeV, a 95\% CL upper limit of 6.5 (resp. 5.4) times the SM cross section is observed (resp. expected). …”
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“…In this work the measurement of the $t\bar{t}$ production in ``boosted'' topologies, i.e. with high transverse momenta of the top quark, $p_{T}(t) > 400$ GeV, in $pp$ collisions at the LHC is presented. …”
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“…The ATLAS Muon Spectrometer aims at a momentum resolution better than 10% for transverse momentum values ranging from pT = 6 GeV to pT = 1TeV. Precision tracking will be performed by Ar-CO2-gas filled Monitored Drift Tube chambers (MDTs), with a single wire resolution of < 100 μm. …”
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“…We find that the LHC mass bound for KK quark and gluon final states is 2675 GeV at its nominal luminosity of 100 fb-1.…”
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“…The ratio of the measured $t\bar{t}H$ signal cross section to the Standard Model expectation is found to be $\mu=2.1^{+1.0}_{-0.9}$, assuming a Higgs-boson mass of 125 GeV.…”
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“…With this approach, the production of top squarks and gluinos are excluded below $\sim700$ GeV and $\sim1.6$ TeV, respectively, independent of the branching ratios, constituting one of the tightest constraints on natural supersymmetry from the LHC. …”
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