INVESTIGADORES
MONTICELLI Fernando Gabriel
artículos
Título:
Measurement of angular correlations in Drell-Yan lepton pairs to probe Z/gamma* boson transverse momentum at √s = 7 TeV with the ATLAS detector
Autor/es:
ATLAS COLLABORATION, G. AAD, F. MONTICELLI, ET AL
Revista:
PHYSICS LETTERS B
Editorial:
ELSEVIER SCIENCE BV
Referencias:
Lugar: Amsterdam; Año: 2013 vol. 720 p. 23 - 121
ISSN:
0370-2693
Resumen:
A measurement of angular correlations in Drell-Yan lepton pairs via the
@f_@h^@? observable is presented. This variable probes the same physics
as the Z/@c^@? boson transverse momentum with a better experimental
resolution. The Z/@c^@?->e^+e^- and Z/@c^@?->@m^+@m^- decays
produced in proton-proton collisions at a centre-of-mass energy of s=7
TeV are used. The data were collected with the ATLAS detector at the LHC
and correspond to an integrated luminosity of 4.6 fb^-^1. Normalised
differential cross sections as a function of @f_@h^@? are measured
separately for electron and muon decay channels. These channels are then
combined for improved accuracy. The cross section is also measured
double differentially as a function of @f_@h^@? for three independent
bins of the Z boson rapidity. The results are compared to QCD
calculations and to predictions from different Monte Carlo event
generators. The data are reasonably well described, in all measured Z
boson rapidity regions, by resummed QCD predictions combined with
fixed-order perturbative QCD calculations or by some Monte Carlo event
generators. The measurement precision is typically better by one order
of magnitude than present theoretical uncertainties.A measurement of
angular correlations in Drell-Yan lepton pairs via the phistar
observable is presented. This variable probes the same physics as the
Z/gamma* boson transverse momentum with a better experimental
resolution. The Z/gamma*->e+e- and Z/gamma*->mu+mu- decays
produced in proton--proton collisions at a centre-of-mass energy of
sqrt(s) = 7 TeV are used. The data were collected with the ATLAS
detector at the LHC and correspond to an integrated luminosity of 4.6
fb-1. Normalised differential cross sections as a function of phistar
are measured separately for electron and muon decay channels. These
channels are then combined for improved accuracy. The cross section is
also measured double differentially as a function of phistar for three
independent bins of the Z boson rapidity. The results are compared to
QCD calculations and to predictions from different Monte Carlo event
generators. The data are reasonably well described, in all measured Z
boson rapidity regions, by resummed QCD predictions combined with
fixed-order perturbative QCD calculations. Some of the Monte Carlo event
generators are also able to describe the data. The measurement
precision is typically better by one order of magnitude than present
theoretical uncertainties.