TY  - JOUR
AU  - LHCb Collaboration (Aaij, R. et al
AU  - Jaimes Elles, S. J.
AU  - Jashal, B. K.
AU  - Martinez-Vidal, F.
AU  - Oyanguren, A.
AU  - Rebollo De Miguel, M.
AU  - Sanderswood, I.
AU  - Zhuo, J.
PY  - 2024
DA  - 2024//
TI  - Curvature-bias corrections using a pseudomass method
T2  - J. Instrum.
JO  - Journal of Instrumentation
SP  - P03010 - 22pp
VL  - 19
IS  - 3
PB  - IOP Publishing Ltd
KW  - Analysis and statistical methods
KW  - Detector alignment and calibration methods (lasers
KW  - sources
KW  - particle-beams)
KW  - Large detector-systems performance
KW  - Performance of High Energy Physics Detectors
AB  - Momentum measurements for very high momentum charged particles, such as muons from electroweak vector boson decays, are particularly susceptible to charge-dependent curvature biases that arise from misalignments of tracking detectors. Low momentum charged particles used in alignment procedures have limited sensitivity to coherent displacements of such detectors, and therefore are unable to fully constrain these misalignments to the precision necessary for studies of electroweak physics. Additional approaches are therefore required to understand and correct for these effects. In this paper the curvature biases present at the LHCb detector are studied using the pseudomass method in proton-proton collision data recorded at centre of mass energy root s = 13 TeV during 2016, 2017 and 2018. The biases are determined using Z -> mu(+)mu(-) decays in intervals defined by the data-taking period, magnet polarity and muon direction. Correcting for these biases, which are typically at the 10(-4) GeV-1 level, improves the Z -> mu(+)mu(-) mass resolution by roughly 18% and eliminates several pathological trends in the kinematic-dependence of the mean dimuon invariant mass.
SN  - 1748-0221
UR  - https://arxiv.org/abs/2311.04670
UR  - https://doi.org/10.1088/1748-0221/19/03/P03010
DO  - 10.1088/1748-0221/19/03/P03010
LA  - English
N1  - WOS:001190907900003
ID  - LHCbCollaborationAaij_etal2024
ER  -