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.

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Search for high mass dijet resonances with a new background prediction method in proton-proton collisions at √ s = 13 TeV The CMS collaboration

A search for the resonant production of high-mass photon pairs is presented. The search focuses on spin-0 and spin-2 resonances with masses between 0.5 and 4.5 TeV, and with widths, relative to the mass, between 1.4 × 10 −4 and 5.6 × 10 −2 . The data sample corresponds to an integrated luminosity of 12.9 fb −1 of proton-proton collisions collected with the CMS detector in 2016 at a center-of-mass energy of 13 TeV. No significant excess is observed relative to the standard model expectation. The results of the search are combined statistically with those previously obtained in 2012 and 2015 at √ s = 8 and 13 TeV, respectively, corresponding to integrated luminosities of 19.7 and 3.3 fb −1 , to derive exclusion limits on scalar resonances produced through gluon-gluon fusion, and on Randall-Sundrum gravitons. The lower mass limits for Randall-Sundrum gravitons range from 1.95 to 4.45 TeV for coupling parameters between 0.01 and 0.2. These are the most stringent limits on Randall-Sundrum graviton production to date.The central feature of the CMS apparatus is a superconducting solenoid of 6 m internal diameter, providing a magnetic field of 3.8 T. Within the solenoid volume are a silicon pixel and strip tracker, a lead tungstate crystal electromagnetic calorimeter (ECAL), and a brass and scintillator hadron calorimeter (HCAL). The tracking detectors cover the pseudorapidity range |η| < 2.5. The ECAL and HCAL, each composed of a barrel and two endcap sections, cover |η| < 3.0, with the boundary between the barrel and endcaps at around |η| = 1.5. Forward calorimeters extend the coverage to |η| < 5.0. The ECAL consists of 75 848 lead tungstate crystals. The barrel section has a granularity ∆η × ∆φ = 0.0174×0.0174, with φ the azimuthal angle, while the endcap sections have a granularity that coarsens progressively up to ∆η × ∆φ = 0.05×0.05. Preshower detectors consisting of two planes of silicon sensors interleaved with a total of 3X 0 of lead are located in front of the endcap sections. Muons are measured within |η| < 2.4 by gas-ionization detectors embedded in the steel flux-return yoke outside the solenoid. A more detailed description of the CMS detector, together with a definition of the coordinate system and the relevant kinematic variables, can be found in Ref. [30].

A peaking structure in the J/ψφ mass spectrum near threshold is observed in B ± → J/ψφK ± decays, produced in pp collisions at √ s = 7 TeV collected with the CMS detector at the LHC. The data sample, selected on the basis of the dimuon decay mode of the J/ψ, corresponds to an integrated luminosity of 5.2 fb −1 . Fitting the structure to an S-wave relativistic Breit-Wigner lineshape above a three-body phase-space nonresonant component gives a signal statistical significance exceeding five standard deviations. The fitted mass and width values are m = 4148.0 ± 2.4 (stat.) ± 6.3 (syst.) MeV and Γ = 28 +15 −11 (stat.) ± 19 (syst.) MeV, respectively. Evidence for an additional peaking structure at higher J/ψφ mass is also reported.Events are chosen using a two-level trigger system. The first level, composed of custom hardware processors, uses information from the muon detectors to select dimuon candidates. The high-level trigger (HLT) runs a special version of the offline software code on a processor farm to select events with nonprompt J/ψ candidates coming from the decays of B mesons.Events containing J/ψ candidates are selected by the HLT dimuon trigger. Because of the increasing LHC instantaneous luminosity, there are two configurations of the HLT, corresponding to two running periods and two distinct data sets. For both data sets, the following require- B The CMS Collaboration