TY  - JOUR
AU  - LHCb Collaboration (Aaij, R. et al
AU  - Martinez-Vidal, F.
AU  - Oyanguren, A.
AU  - Ruiz Valls, P.
AU  - Sanchez Mayordomo, C.
PY  - 2014
DA  - 2014//
TI  - First Measurement of the Charge Asymmetry in Beauty-Quark Pair Production
T2  - Phys. Rev. Lett.
JO  - Physical Review Letters
SP  - 082003
EP  - 9pp
VL  - 113
IS  - 8
PB  - Amer Physical Soc
AB  - The difference in the angular distributions between beauty quarks and antiquarks, referred to as the charge asymmetry, is measured for the first time in b (b) over bar pair production at a hadron collider. The data used correspond to an integrated luminosity of 1.0 fb(-1) collected at 7 TeV center-of-mass energy in proton-proton collisions with the LHCb detector. The measurement is performed in three regions of the invariant mass of the b (b) over bar system. The results obtained are A(C)(b (b) over bar) (40 < M-b<(b)over bar> < 75 GeV/c(2)) = 0.4 +/- 0.4 +/- 0.3%, A(C)(b (b) over bar) (75 < M-b<(b)over bar> < 105 GeV/c(2)) = 2.0 +/- 0.9 +/- 0.6%, A(C)(b (b) over bar) (M-b (b) over bar > 10(5) GeV/c(2)) = 1.6 +/- 1.7 +/- 0.6%,where A(C)(b (b) over bar) is defined as the asymmetry in the difference in rapidity between jets formed from the beauty quark and antiquark, where in each case the first uncertainty is statistical and the second systematic. The beauty jets are required to satisfy 2 < eta < 4, E-T > 20 GeV, and have an opening angle in the transverse plane Delta phi > 2.6 rad. These measurements are consistent with the predictions of the standard model.
SN  - 0031-9007
UR  - http://arxiv.org/abs/1406.4789
UR  - https://doi.org/10.1103/PhysRevLett.113.082003
DO  - 10.1103/PhysRevLett.113.082003
LA  - English
N1  - WOS:000346504200005
ID  - LHCbCollaborationAaij_etal2014
ER  -