INVESTIGADORES
MONTICELLI Fernando Gabriel
artículos
Título:
Jet energy measurement with the ATLAS detector in proton-proton collisions at √s = 7 TeV
Autor/es:
ATLAS COLLABORATION, G. AAD, F. MONTICELLI, ET AL
Revista:
EUROPEAN PHYSICAL JOURNAL C - PARTICLES AND FIELDS
Editorial:
SPRINGER
Referencias:
Lugar: Berlin; Año: 2012 vol. 213 p. 1 - 23
ISSN:
1434-6044
Resumen:
The jet energy scale (JES) and its systematic uncertainty are determined
for jets measured with the ATLAS detector at the LHC in proton-proton
collision data at a centre-of-mass energy of sqrt(s) = 7 TeV
corresponding to an integrated luminosity of 38 inverse pb. Jets are
reconstructed with the anti-kt algorithm with distance parameters R=0.4
or R=0.6. Jet energy and angle corrections are determined from Monte
Carlo simulations to calibrate jets with transverse momenta pt > 20
GeV and pseudorapidities eta<4.5. The JES systematic uncertainty is
estimated using the single isolated hadron response measured in situ and
in test-beams. The JES uncertainty is less than 2.5% in the central
calorimeter region (eta<0.8) for jets with 60 < pt < 800 GeV,
and is maximally 14% for pt < 30 GeV in the most forward region
3.2<eta<4.5. The uncertainty for additional energy from multiple
proton-proton collisions in the same bunch crossing is less than 1.5%
per additional collision for jets with pt > 50 GeV after a dedicated
correction for this effect. The JES is validated for jet transverse
momenta up to 1 TeV to the level of a few percent using several in situ
techniques by comparing a well-known reference such as the recoiling
photon pt, the sum of the transverse momenta of tracks associated to the
jet, or a system of low-pt jets recoiling against a high-pt jet. More
sophisticated jet calibration schemes are presented based on calorimeter
cell energy density weighting or hadronic properties of jets, providing
an improved jet energy resolution and a reduced flavour dependence of
the jet response. The JES systematic uncertainty determined from a
combination of in situ techniques are consistent with the one derived
from single hadron response measurements over a wide kinematic range.
The nominal corrections and uncertainties are derived for isolated jets
in an inclusive sample of high-pt jets.