3 research outputs found
New FOCUS results on charm mixing and CP violation
We present a summary of recent results on CP violation and
mixing in the charm quark sector based on a high statistics sample collected
by photoproduction experiment FOCUS (E831 at Fermilab). We have measured the
difference in lifetimes for the D0 decays: D0 --> K-pi+ and
D0 --> K-K+ . This translates
into a measurement of the y_cp mixing parameter in the
D0/D0bar system, under the
assumptions that K+K- is an equal mixture of CP odd and CP even eigenstates,
and CP violation is negligible in the neutral charm meson system.
We verified the latter assumption by searching for a CP violating asymmetry in
the Cabibbo suppressed decay modes D+ --> K-K+pi+ ,
D0 --> K-K+ and D0 --> pi-pi+ . We show
preliminary results on a measurement of the branching
ratio Gamma(D*+ --> pi+(K+pi-))/Gamma(D*+ --> pi+(K-pi+))
Preliminay results on charmed meson spectroscopy.
We report the preliminary measurement by the FOCUS Collaboration
(E831 at Fermilab) of masses and widths of the L=1 charm mesons D*0_2
and D*+_2.
The fit of the invariant mass distribution
requires an additional term to account for a broad structure over background