Search for WH production with a light Higgs boson decaying to prompt electron-jets in proton-proton collisions at s\sqrt{s}=7 TeV with the ATLAS detector

A search is performed for WH production with a light Higgs boson decaying to hidden-sector particles resulting in clusters of collimated electrons, known as electron-jets. The search is performed with 2.04 fb-1 of data collected in 2011 with the ATLAS detector at the LHC in proton-proton collisions at $\sqrt{s}$=7 TeV. One event satisfying the signal selection criteria is observed, which is consistent with the expected background rate. Limits on the product of the WH production cross section and the branching ratio of a Higgs boson decaying to prompt electron-jets are calculated as a function of a Higgs boson mass in the range from 100 GeV to 140 GeV.Peer Reviewe

Search for diphoton events with large missing transverse momentum in 1 fb(-1) of 7 TeV proton-proton collision data with the ATLAS detector ATLAS Collaboration

A search for diphoton events with large missing transverse momentum has been performed using 1.07 fb -1 of proton-proton collision data at s=7 TeV recorded with the ATLAS detector. No excess of events was observed above the Standard Model prediction and 95% Confidence Level (CL) upper limits are set on the production cross section for new physics. The limits depend on each model parameter space and vary as follows: Λ<(22-129) fb in the context of a generalised model of gauge-mediated supersymmetry breaking (GGM) with a bino-like lightest neutralino, σ<(27-91) fb in the context of a minimal model of gauge-mediated supersymmetry breaking (SPS8), and σ<(15-27) fb in the context of a specific model with one universal extra dimension (UED). A 95% CL lower limit of 805 GeV, for bino masses above 50 GeV, is set on the GGM gluino mass. Lower limits of 145 TeV and 1.23 TeV are set on the SPS8 breaking scale Λ and on the UED compactification scale 1/R, respectively. These limits provide the most stringent tests of these models to date. © 2012 CERN

Measurement of the isolated diphoton cross-section in pp collisions at sqrt(s) = 7 TeV with the ATLAS detector

The ATLAS experiment has measured the production cross-section of events with two isolated photons in the final state, in proton-proton collisions at sqrt(s) = 7 TeV. The full data set acquired in 2010 is used, corresponding to an integrated luminosity of 37 pb^-1. The background, consisting of hadronic jets and isolated electrons, is estimated with fully data-driven techniques and subtracted. The differential cross-sections, as functions of the di-photon mass, total transverse momentum and azimuthal separation, are presented and compared to the predictions of next-to-leading-order QCD.Comment: 15 pages plus author list (27 pages total), 9 figures, 2 tables, final version to appear in Physical Review

Search for diphoton events with large missing transverse momentum in 1 fb^-1 of 7 TeV proton–proton collision data with the ATLAS detector

A search for diphoton events with large missing transverse momentum has been performed using 1.07 fb−1of proton–proton collision data at √s=7  TeV recorded with the ATLAS detector. No excess of events was observed above the Standard Model prediction and 95% Confidence Level (CL) upper limits are set on the production cross section for new physics. The limits depend on each model parameter space and vary as follows: σ<(22–129) fb in the context of a generalised model of gauge-mediated supersymmetry breaking (GGM) with a bino-like lightest neutralino, σ<(27–91) fb in the context of a minimal model of gauge-mediated supersymmetry breaking (SPS8), and σ< (15–27) fb in the context of a specific model with one universal extra dimension (UED). A 95% CL lower limit of 805 GeV, for bino masses above 50 GeV, is set on the GGM gluino mass. Lower limits of 145 TeV and 1.23 TeV are set on the SPS8 breaking scale ∧ and on the UED compactification scale 1/R, respectively. These limits provide the most stringent tests of these models to date

Search for diphoton events with large missing transverse momentum in 1 fb(-1) of 7 TeV proton-proton collision data with the ATLAS detector ATLAS Collaboration

A search for diphoton events with large missing transverse momentum has been performed using 1.07 fb(-1) of proton-proton collision data at root s = 7 TeV recorded with the ATLAS detector. No excess of events was observed above the Standard Model prediction and 95% Confidence Level (CL) upper limits are set on the production cross section for new physics. The limits depend on each model parameter space and vary as follows: sigma < (22-129) fb in the context of a generalised model of gauge-mediated supersymmetry breaking (GGM) with a bino-like lightest neutralino, sigma < (27-91) fb in the context of a minimal model of gauge-mediated supersymmetry breaking (SPS8), and sigma < (15-27) fb in the context of a specific model with one universal extra dimension (UED). A 95% CL lower limit of 805 GeV, for bino masses above 50 GeV, is set on the GGM gluino mass. Lower limits of 145 TeV and 1.23 TeV are set on the SPS8 breaking scale Lambda and on the UED compactification scale 1/R, respectively. These limits provide the most stringent tests of these models to date. (C) 2012 CERN. Published by Elsevier B.V. All rights reserved. RI Sivoklokov, Sergey/D-8150-2012; Li, Xuefei/C-3861-2012; Smirnov, Sergei/F-1014-2011; Gladilin, Leonid/B-5226-2011; Barreiro, Fernando/D-9808-2012; Prokoshin, Fedor/E-2795-2012; Fazio, Salvatore /G-5156-2010; Orlov, Ilya/E-6611-2012; Doyle, Anthony/C-5889-2009; Alexa, Calin/F-6345-2010; Moorhead, Gareth/B-6634-2009; Livan, Michele/D-7531-2012; Takai, Helio/C-3301-2012; Petrucci, Fabrizio/G-8348-2012; Jones, Roger/H-5578-2011; Fabbri, Laura/H-3442-2012; Kurashige, Hisaya/H-4916-2012; Villa, Mauro/C-9883-2009; Delmastro, Marco/I-5599-201

Search for diphoton events with large missing transverse momentum in 1 fb(-1) of 7 TeV proton-proton collision data with the ATLAS detector ATLAS Collaboration

A search for diphoton events with large missing transverse momentum has been performed using 1.07 fb(-1) of proton-proton collision data at root s = 7 TeV recorded with the ATLAS detector. No excess of events was observed above the Standard Model prediction and 95% Confidence Level (CL) upper limits are set on the production cross section for new physics. The limits depend on each model parameter space and vary as follows: sigma < (22-129) fb in the context of a generalised model of gauge-mediated supersymmetry breaking (GGM) with a bino-like lightest neutralino, sigma < (27-91) fb in the context of a minimal model of gauge-mediated supersymmetry breaking (SPS8), and sigma < (15-27) fb in the context of a specific model with one universal extra dimension (UED). A 95% CL lower limit of 805 GeV, for bino masses above 50 GeV, is set on the GGM gluino mass. Lower limits of 145 TeV and 1.23 TeV are set on the SPS8 breaking scale Lambda and on the UED compactification scale 1/R, respectively. These limits provide the most stringent tests of these models to date. (C) 2012 CERN. Published by Elsevier B.V. All rights reserved