Evidence for an anomalous like-sign dimuon charge asymmetry

0351662 - FZÚ 2011 RIV US eng J - Journal Article
Abazov, V. M. - Abbott, B. - Abolins, M. - Kupčo, Alexander - Lokajíček, Miloš
Evidence for an anomalous like-sign dimuon charge asymmetry.
Physical Review D: Particles, Fields, Gravitation and Cosmology. Roč. 82, č. 3 (2010), 032001/1-032001/30. ISSN 1550-7998
R&D Projects: GA MŠMT LC527; GA MŠMT LA08047
Institutional research plan: CEZ:AV0Z10100502
Keywords : D0 * dimuon * asymmetry * mesons
Subject RIV: BF - Elementary Particles and High Energy Physics
Impact factor: 4.964, year: 2010
http://link.aps.org/doi/10.1103/PhysRevD.82.032001

We measure the charge asymmetry $A$ of like-sign dimuon events in 6.1 fb$^{-1}$ of $p/bar{p}$ collisions recorded with the D0 detector at a center-of-mass energy $/sqrt{s} = 1.96$ TeV at the Fermilab Tevatron collider. From $A$, we extract the like-sign dimuon charge asymmetry in semileptonic $b$-hadron decays: $/aslb = -0.00957 /pm 0.00251 ({/rm stat}) /pm 0.00146 ({/rm syst})$. This result differs by 3.2 standard deviations from the standard model prediction $/aslb(SM) = (-2.3^{+0.5}_{-0.6}) /times 10^{-4}$ and provides first evidence of anomalous CP-violation in the mixing of neutral $B$ mesons.
Permanent Link: http://hdl.handle.net/11104/0191368