Measurement of the Ratio of Branching Ratios B($B^+ \to J/\psi \pi^+$) / B($B^+ \to J/\psi K^+$) and Search for $B_c^+$

Abstract

This thesis reports on a measurement of the branching ratio of the Cabibbo-suppressed decay B where J/-+ The data were collected by the Collider Detector at Fermilab during 1992-1995 and correspond to an integrated luminosity of 110 pb in pp collisions at = 1.8 TeV. A signal of 28t 0 events is observed and we determine the ratio of branching ratios B(B-* J/K) to be (5.0it ± 0.1)%, where the first uncertainties are statistical and the second are systematic. Using the world average value for B(B-+ J/ i/,K+), we calculate the branching ratio B(B-J/nrj to be (5.0t) x 10. We also search for the decay B J//,+ and report a 95% confidence level limit on a(B) B(B-+ J/rr)/a(B) B(B-+ J/'bK) as a function of the B lifetime.