Abstract:
Using 355 pb-1 of data collected by the CDF II detector in p[overline p] collisions at sqrt(s)=1.96 TeV at the Fermilab Tevatron, we study the fully reconstructed hadronic decays B(s)0-->D(s)-pi+ and B(s)0-->D(s)-pi+pi+pi-. We present the first measurement of the ratio of branching fractions [script B](Bs0-->Ds-pi+pi+pi-)/[script B](B0-->D-pi+pi+pi-)=1.05$\pm$0.10(stat)$\pm$0.22(syst). We also update our measurement of [script B](Bs0-->Ds-pi+)/[script B](B0-->D-pi+) to 1.13$\pm$0.08(stat)$\pm$0.23(syst), improving the statistical uncertainty by more than a factor of 2. We find [script B](Bs0-->Ds-pi+)=[3.8$\pm$0.3(stat)$\pm$1.3(syst)]{\AA}~10-3 and [script B](Bs0-->Ds-pi+pi+pi-)=[8.4$\pm$0.8(stat)$\pm$3.2(syst)]{\AA}~10-3.