Search for the Decays B-(s)(0) -> e(+)mu(-) and B-(s)(0) -> e(+)e(-) in CDF Run II

Abstract

We report results from a search for the lepton flavor violating decays B-s(0) -> e(+)mu(-) and B-0 -> e(+)mu(-), and the flavor-changing neutral-current decays B-s(0) -> e(+)e(-) and B-0 -> e(+)e(-). The analysis uses data corresponding to 2 fb(-1) of integrated luminosity of p (p) over bar collisions at root s = 1.96 TeV collected with the upgraded Collider Detector (CDF II) at the Fermilab Tevatron. The observed number of B-0 and B-s(0) candidates is consistent with background expectations. The resulting Bayesian upper limits on the branching ratios at 90% credibility level are B(B-s(0) -> e(+)mu(-) ) < 2.0 x 10(-7), B(B-0 -> e(+)mu(-)) < 6.4 x 10(-8), B(B-s(0) -> e(+)e(-) ) < 2.8 x 10(-7), and B(B-0 -> e(+)e(-)) < 8.3 x 10(-8). From the limits on B(B-(s)(0) -> e(+)mu(-)), the following lower bounds on the Pati-Salam leptoquark masses are also derived: M-LQ(B-s(0) -> e(+)mu(-)) > 47.8 TeV/c(2), and M-LQ(B-0 -> e(+)mu(-)) > 59.3 TeV/c(2), at 90% credibility level.