Results are presented from a search for the rare decays Bs(0)→μ+ μ- and B(0)→μ+ μ- in pp collisions at sqrt[s]=7 and 8 TeV, with data samples corresponding to integrated luminosities of 5 and 20  fb(-1), respectively, collected by the CMS experiment at the LHC. An unbinned maximum-likelihood fit to the dimuon invariant mass distribution gives a branching fraction B(Bs(0)→μ+ μ-)=(3.0(-0.9)(+1.0))×10(-9), where the uncertainty includes both statistical and systematic contributions. An excess of Bs(0)→μ+ μ- events with respect to background is observed with a significance of 4.3 standard deviations. For the decay B(0)→μ+ μ- an upper limit of B(B(0)→μ+ μ-)<1.1×10(-9) at the 95% confidence level is determined. Both results are in agreement with the expectations from the standard model.

Search for a Higgs boson decaying into a Z and a photon in pp collisions at √ s = 7 and 8 TeVThe CMS Collaboration * Abstract A search for a Higgs boson decaying into a Z boson and a photon is described. The analysis is performed using proton-proton collision datasets recorded by the CMS detector at the LHC. Events were collected at center-of-mass energies of 7 TeV and 8 TeV, corresponding to integrated luminosities of 5.0 fb −1 and 19.6 fb −1 , respectively. The selected events are required to have opposite-sign electron or muon pairs. No excess above standard model predictions has been found in the 120-160 GeV mass range and the first limits on the Higgs boson production cross section times the H → Zγ branching fraction at the LHC have been derived. The observed limits are between about 4 and 25 times the standard model cross section times the branching fraction. The observed and expected limits for m γ at 125 GeV are within one order of magnitude of the standard model prediction. Models predicting the Higgs boson production cross section times the H → Zγ branching fraction to be larger than one order of magnitude of the standard model prediction are excluded for most of the 125-157 GeV mass range. The observation of a new resonance decaying to two bosons and with decay modes and properties consistent with those of the standard model (SM) Higgs boson has been reported by the ATLAS [1, 2] and CMS [3, 4] collaborations. Measurements of the basic properties of this resonance, such as the mass [5] and the coupling strength to vector bosons and fermions [1-4, 6], have been reported. Within the SM, the partial width for the H → Zγ decay channel (Γ Zγ ) is rather small, resulting in a branching fraction between 0.11% and 0.25% in the 120-160 GeV [7, 8] mass range. A measurement of Γ Zγ provides important information on the underlying dynamics of the Higgs sector because it is induced by loops of heavy charged particles, just as for the H → γγ decay channel. The contributing diagrams to Γ Zγ are shown in Fig. 1. Γ Zγ is sensitive to physics beyond the SM, and could be substantially modified by new charged particles without affecting the gluon-gluon fusion Higgs boson production cross section [9], such as derived from an extended Higgs sector [10], or by the presence of new scalars [11, 12].γ Z W W H H Z γ γ Z f f f H Figure 1: Diagrams contributing to Γ Zγ .This paper describes the first search for a Higgs boson in the H → Zγ final state at the LHC in the 120-160 GeV mass range, with the Z boson decaying into an electron or a muon pair. This is a clean final-state topology with an effective mass peak resolution of about 1-3%. To improve the sensitivity of the search, the selected dilepton-plus-photon events are subdivided into classes according to their mass resolution and the signal-to-background ratio, for both the electron and muon channels. The dominant backgrounds consist of the irreducible contribution from the SM Zγ production, and the reducible backgrounds from final-state-radiation in Drell-Yan or Z decays, an...

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We report on measurements of the 1S, 2S and 3S di erential cross sections d 2 =dp T dy jyj 0:4 , as well as on the 1S polarization in pp collisions at p s = 1:8TeV using a sample of 77 3 pb ,1 collected by the Collider Detector at Fermilab.The three resonances were reconstructed through the decay ! + , . The measured angular distribution of the muons in the 1S rest frame is consistent with unpolarized meson production.

Measurements of pp-+n + n m +X at Vs = 44 and 62 GeV are compared. The data are taken under identical conditions utilizing clean proton-proton collisions from the CERN intersecting storage rings and confirm scaling to 5%. The observed JU + JT yield is a factor of 1.6 ± 0.2 larger than estimated from a simple parton model but is consistent with QCD. The p T dependence of the muon pairs agrees well with expectations from QCD.