The Collider Detector at Fermilab in Run II has often
been dubbed the Charm Detector Facility due to its
capability of recording huge samples of charm mesons,
identified by their signature of a decay vertex displaced
from the beam axis.
Presently CDF has more than 106 D0-->Kpi and
D+/--->Kpipi decays, and has established itself as a
world class facility for Charm physics.
A team of CDF researchers from Italy and the U.S. has
studied the decay chain D*+-->D0pi-->(K+K-)pi+ and
D*+-->D0pi-->(pi+pi-)pi+, and their charge conjugate
counterparts, to determine to what extent the probabilities
of D0 and anti-D0 decaying into the K+K- and pi+pi-
channels are the same, or if a charge-parity ("CP")
The Standard Model predicts CP asymmetries well below the 1%
level in these decay rates, but it is easy to conceive of
alternative models that could produce more sizeable effects.
Using data from the first year of Run II, corresponding to
120 pb-1, very clean charm samples were selected.
Careful analysis has allowed CDF to put the most stringent
limits to date on direct CP asymmetries:
ACP(pi+pi-)=1.0+/-1.3(stat)+/-0.6(sys)%, both consistent
with no CP asymmetry.
After the recent discovery of CP violation in B0-->K+pi-
decay rates and the very well known effects in K0 decays,
this result confirm that charm mesons might be the only
heavy flavor mesons that do not exhibit violations of this