Abstract: The algorithms used by the ATLAS Collaboration to reconstruct and identify prompt photons are described. Measurements of the photon identification efficiencies are reported, using 4.9 fb(-1) of pp collision data collected at the LHC at root s = 7 TeV and 20.3 fb-1 at root s = 8 TeV. The efficiencies are measured separately for converted and unconverted photons, in four different pseudorapidity regions, for transverse momenta between 10 GeV and 1.5 TeV. The results from the combination of three data-driven techniques are compared to the predictions from a simulation of the detector response, after correcting the electromagnetic shower momenta in the simulation for the average differences observed with respect to data. Data-to-simulation efficiency ratios used as correction factors in physics measurements are determined to account for the small residual efficiency differences. These factors are measured with uncertainties between 0.5% and 10% in 7 TeV data and between 0.5% and 5.6% in 8 TeV data, depending on the photon transverse momentum and pseudorapidity.

Abstract: A combination of measurements sensitive to the CKM angle gamma from LHCb is performed. The inputs are from analyses of time-integrated B+ -> DK+, B-0 -> DK*(0), B-0 -> DK+ pi(-) and B+ -> DK+ pi(+) pi(-) tree-level decays. In addition, results from a time-dependent analysis of B-s(0) -> (DsK +/-)-K--/+ decays are included. The combination yields = (72: 2(-7.3)(+6:8) 7 : 3)degrees, where the uncertainty includes systematic effects. The 95.5% confidence level interval is determined to be gamma is an element of [55.9, 85.2]degrees. A second combination is investigated, also including measurements from B+ -> DK+, B-0 -> DK*(0), B-0 -> DK+ pi(-) and B+ -> DK+ pi(+) pi decays, which yields compatible results.

Abstract: In recent years, direct detection, indirect detection, and collider experiments have placed increasingly stringent constraints on particle dark matter, exploring much of the parameter space associated with the WIMP paradigm. In this paper, we focus on the subset of WIMP models in which the dark matter annihilates in the early universe through couplings to either the Standard Model Z or the Standard Model Higgs boson. Considering fermionic, scalar, and vector dark matter candidates within a model-independent context, we fi nd that the overwhelming majority of these dark matter candidates are already ruled out by existing experiments. In the case of Z mediated dark matter, the only scenarios that are not currently excluded are those in which the dark matter is a fermion with an axial coupling and with a mass either within a few GeV of the Z resonance (m(D M) similar or equal to m(Z)/2) or greater than 200 GeV, or with a vector coupling and with m(DM) > 6TeV. Several Higgs mediated scenarios are currently viable if the mass of the dark matter is near the Higgs pole (m(DM) similar or equal to m(H) /2). Otherwise, the only scenarios that are not excluded are those in which the dark matter is a scalar (vector) heavier than 400 GeV (1160 GeV) with a Higgs portal coupling, or a fermion with a pseudoscalar (CP violating) coupling to the Standard Model Higgs boson. With the exception of dark matter with a purely pseudoscalar coupling to the Higgs, it is anticipated that planned direct detection experiments will probe nearly the entire range of models considered in this study.