Speaker
Dr
Lars Sonnenschein
(RWTH Aachen IIIA)
Description
A search for CP violation has been performed in a sample of semileptonic
Bs decays corresponding to approximately 5 fb^-1 of data collected by the
D0 detector in Run II at the Fermilab Tevatron collider.
A time-dependent fit to the distributions of Bs candidates yields the
flavour-specific asymmetry
as_fs = [-1.7 pm 9.1 (stat) +1.2-2.3 (syst)] x 10^-3, corresponding to the
most precise measurement to date for this CP violation parameter.
Furthermore a search for the semi-inclusive process Bs to Ds(*)Ds(*) has
been performed on a data sample of 2.8fb^-1. 26.6 pm 8.4 signal events are
observed with a significance of 3.2 standard deviations above background,
leading to a branching ratio of 0.035 pm 0.010 (stat) pm 0.011 (syst).
Under certain theoretical assumptions, these double-charm final states
saturate CP-even eigenstates in the Bs decays, resulting in a width
difference of DeltaGamma_s(CP)/Gamma_s = 0.072 pm 0.021 (stat) pm 0.022
(syst).
Primary author
Dr
Lars Sonnenschein
(RWTH Aachen IIIA)
