Learn More
The NA48 experiment at CERN has performed a new measurement of direct CP violation, based on data taken in 1997 by simultaneously collecting K L and K S decays into π 0 π 0 and π + π −. The result for the CP violating parameter Re (ε ′ /ε) is (18.5 ± 4.5(stat) ± 5.8(syst)) × 10 −4. 1 Introduction CP violation has been observed so far only in the decays of(More)
A measurement of the Higgs boson mass is presented based on the combined data samples of the ATLAS and CMS experiments at the CERN LHC in the H→γγ and H→ZZ→4ℓ decay channels. The results are obtained from a simultaneous fit to the reconstructed invariant mass peaks in the two channels and for the two experiments. The measured masses from the individual(More)
A new measurement of the ratio of the CP-violating amplitudes for KL-~ 21t ° and KL ~ ~+It-is reported. The measured value for R = J~/0o/r/+_[ 2 is 0.9878 ± 0.0026 ± 0.0030, where the first error is the statistical uncertainty and the second is the estimate of the systematic uncertainty. This gives a value for the parameter describing direct CP
The direct CP violation parameter Re(ε ′ /ε) has been measured from the decay rates of neutral kaons into two pions using the NA48 detector at the CERN SPS. With 3.3 million KL → π 0 π 0 events collected during the 1998 and 1999 running periods, a result of Re(ε ′ /ε) = (15.0 ± 2.7)×10 −4 has been obtained. The result combined with the published 1997 sample(More)
This Letter reports on a search for narrow high-mass resonances decaying into dilepton final states. The data were recorded by the ATLAS experiment in pp collisions at √s=7  TeV at the Large Hadron Collider and correspond to a total integrated luminosity of 1.08 (1.21)  fb(-1) in the e(+)e(-) (μ(+)μ(-)) channel. No statistically significant excess above the(More)
The luminosity calibration for the ATLAS detector at the LHC during pp collisions at √ s = 7 TeV in 2010 and 2011 is presented. Evaluation of the luminosity scale is performed using several luminosity-sensitive detectors, and comparisons are made of the long-term stability and accuracy of this calibration applied to the pp collisions at √ s = 7 TeV. A(More)
Results of a search for new phenomena in events with an energetic photon and large missing transverse momentum in proton-proton collisions at sqrt[s] = 7 TeV are reported. Data collected by the ATLAS experiment at the LHC corresponding to an integrated luminosity of 4.6 fb(-1) are used. Good agreement is observed between the data and the standard model(More)
A search for new heavy particles manifested as resonances in two-jet final states is presented. The data were produced in 7 TeV proton-proton collisions by the LHC and correspond to an integrated luminosity of 315  nb⁻¹ collected by the ATLAS detector. No resonances were observed. Upper limits were set on the product of cross section and signal acceptance(More)