Measurement of partial widths and search for direct CP violation in D(0) meson decays to K(-)K(+) and pi(-)pi(+)

We present a measurement of relative partial widths and decay rate CP asymmetries in K(-)K(+) and pi(-)pi(+) decays of D(0) mesons produced in p(p) over bar collisions at root s = 1.96 TeV. We use a sample of 2x10(5) D(*+)-> D(0)pi(+) (and charge conjugate) decays with the D(0) decaying to K(-)pi(+), K(-)K(+), and pi(-)pi(+), corresponding to 123 pb(-1) of data collected by the Collider Detector at Fermilab II experiment at the Fermilab Tevatron collider. No significant direct CP violation is observed. We measure Gamma(D(0)-> K(-)K(+))/Gamma(D(0)-> K(-)pi(+)) = 0.0992 +/- 0.0011 +/- 0.0012, Gamma(D(0)->pi(-)pi(+))/Gamma(D(0)-> K(-)pi(+)) = 0.035 94 +/- 0.000 54 +/- 0.000 40, A(CP)(K(-)K(+)) = (2.0 +/- 1.2 +/- 0.6)%, and A(CP)(pi(-)pi(+)) = (1.0 +/- 1.3 +/- 0.6)%, where, in all cases, the first uncertainty is statistical and the second is systematic.