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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].

Inclusive jet spectra from pp and PbPb collisions at a nucleon-nucleon center-of-mass energy of 2.76 TeV, collected with the CMS detector at the LHC, are presented. Jets are reconstructed with three different distance parameters (R = 0.2, 0.3 and 0.4) for transverse momentum (p T ) greater than 70 GeV/c and pseudorapidity |η| < 2. Next-toleading-order quantum chromodynamic calculations with non-perturbative corrections are found to over-predict jet production cross sections in pp for small distance parameters. The jet nuclear modification factors for PbPb compared to pp collisions, show a steady decrease from peripheral to central events, along with a weak dependence on the jet p T . They are found to be independent of the distance parameter in the measured kinematic range.

Differential and double-differential cross sections for the production of top quark pairs in proton-proton collisions at 13 TeV are measured as a function of jet multiplicity and of kinematic variables of the top quarks and the top quark-antiquark system. This analysis is based on data collected by the CMS experiment at the LHC corresponding to an integrated luminosity of 2.3 fb −1 . The measurements are performed in the lepton+jets decay channels with a single muon or electron in the final state. The differential cross sections are presented at particle level, within a phase space close to the experimental acceptance, and at parton level in the full phase space. The results are compared to several standard model predictions. Published in Physical Review D asIt should be remarked that events with a hadronic and a leptonic particle-level top quark are not required to be +jets events at the parton level. As an example, in Fig. 1 the relation between the p T (t h ) values at particle and parton level is shown. The CMS detectorThe central feature of the CMS detector 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), each composed of a barrel and two endcap sections. Forward calorimeters extend the η coverage provided by the barrel and endcap detectors. Muons C The CMS Collaboration

The energy resolution of a highly granular 1 m 3 analogue scintillator-steel hadronic calorimeter is studied using charged pions with energies from 10 GeV to 80 GeV at the CERN SPS. The energy resolution for single hadrons is determined to be approximately 58%/ E/GeV. This resolution is improved to approximately 45%/ E/GeV with software compensation techniques. These techniques take advantage of the event-by-event information about the substructure of hadronic showers which is provided by the imaging capabilities of the calorimeter. The energy reconstruction is improved either with corrections based on the local energy density or by applying a single correction factor to the event energy sum derived from a global measure of the shower energy density. The application of the compensation algorithms to GEANT4 simulations yield resolution improvements comparable to those observed for real data.