No abstract available

[en] We present the strategy in extracting information on triple gauge boson couplings in WW production and summarize the expected limits on WWV couplings from the ATLAS experiment at the LHC

[en] The WW production via leptonic decay is studied using next-to-leading order generators. The output from the Baur, Han and Ohnemus (BHO) NLO code is compared with MC-NLO generator

No abstract available

[en] We present a strategy for the direct measurement of the WW production rate at the LHC with ATLAS. Sensitivity limits on anomalous WWZ and WW couplings are assessed with account of the effects of higher order QCD corrections and contributions from other theoretical and detector related systematics. (author)

[en] Studies of diboson production in pp collisions at center of mass energy of 14 TeV, predicted by the Standard Model electroweak interactions, will be performed with the ATLAS detector. Signals of the WW, ZW, ZZ, Wγ, Zγ channels are searched through their multi-lepton/photon final states while the sources of background are also studied. On this basis, lepton identification and selection efficiencies are optimized using events of Z decays to two leptons and the missing energy resolution and its systematic errors are studied via W boson decays to lepton and neutrino. Analysis with advanced techniques such as Boosted Decision Trees are applied for the WW, WZ and W/Z_γ signals. Finally, the cross section measurements systematic and statistical uncertainties are estimated with respect to integrated luminosity of 0.1 to 10fb^-1. The method of extracting anomalous triple-gauge coupling measurement is also presented

[en] This Letter presents a search for magnetic monopoles with the ATLAS detector at the CERN Large Hadron Collider using an integrated luminosity of 2.0 fb^-1 of pp collisions recorded at a center-of-mass energy of √s=7 TeV. No event is found in the signal region, leading to an upper limit on the production cross section at 95% confidence level of 1.6 /ε fb for Dirac magnetic monopoles with the minimum unit magnetic charge and with mass between 200 GeV and 1500 GeV, where is the monopole reconstruction efficiency. The efficiency is high and uniform in the fiducial region given by pseudorapidity |η| ≤ 1.37 and transverse kinetic energy 600-700≤E^kin sinθ≤1400 GeV. The minimum value of 700 GeV is for monopoles of mass 200 GeV, whereas the minimum value of 600 GeV is applicable for higher mass monopoles. Therefore, the upper limit on the production cross section at 95% confidence level is 2 fb in this fiducial region. Assuming the kinematic distributions from Drell-Yan pair production of spin-1/2 Dirac magnetic monopoles, the efficiency is in the range 1%-10%, leading to an upper limit on the cross section at 95% confidence level that varies from 145 fb to 16 fb for monopoles with mass between 200 GeV and 1200 GeV. This limit is weaker than the fiducial limit because most of these monopoles lie outside the fiducial region. (authors)

[en] Nearly 50 years ago, theoretical physicists proposed that a field permeates the universe and gives energy to the vacuum. This field was required to explain why some, but not all, fundamental particles have mass. Numerous precision measurements during recent decades have provided indirect support for the existence of this field, but one crucial prediction of this theory has remained unconfirmed despite 30 years of experimental searches: the existence of a massive particle, the standard model Higgs boson. The ATLAS experiment at the Large Hadron Collider at CERN has now observed the production of a new particle with a mass of 126 giga-electron volts and decay signatures consistent with those expected for the Higgs particle. This result is strong support for the standard model of particle physics, including the presence of this vacuum field. The existence and properties of the newly discovered particle may also have consequences beyond the standard model itself. (authors)