Claude Guyot

TL;DR: In this paper , the authors present a measurement of the electroweak production of two jets in association with a $Z\gamma$ pair, with the $Z$ boson decaying into two neutrinos.

TL;DR: In this paper, two-charged pion correlations were studied at rest with the CPLEAR detector at the Low-Energy Antiproton Ring (LEAR) and the correlation strength was found to be > 1.

Abstract: ATLAS measurements of the azimuthal anisotropy in lead–lead collisions at √ sNN = 2.76 TeV are shown using a dataset of approximately 7 μb−1 collected at the LHC in 2010. The measurements are performed for charged particles with transverse momenta 0.5 < pT < 20 GeV and in the pseudorapidity range |η| < 2.5. The anisotropy is characterized by the Fourier coefficients, vn , of the charged-particle azimuthal angle distribution for n = 2–4. The Fourier coefficients are evaluated using multi-particle cumulants calculated with the generating function method. Results on the transverse momentum, pseudorapidity and centrality dependence of the vn coefficients are presented. The elliptic flow, v2, is obtained from the two-, four-, sixand eight-particle cumulants while higher-order coefficients, v3 and v4, are determined with twoand four-particle cumulants. Flow harmonics vn measured with four-particle cumulants are significantly reduced compared to the measurement involving two-particle cumulants. A comparison to vn measurements obtained using different analysis methods and previously reported by the LHC experiments is also shown. Results of measurements of flow fluctuations evaluated with multiparticle cumulants are shown as a function of transverse momentum and the collision centrality. Models of the initial spatial geometry and its fluctuations fail to describe the flow fluctuations measurements.