Measurement Of B0 Ds D Branching Fractions And B0 Ds D Polarization With A Partial Reconstruction Technique PDF Download

Preliminary results are presented on the branching fractions B (B[sup 0] --> D[sub s][sup *+]D[sup *-]) and B (D[sub s][sup +] --> [phi][pi][sup +]), based on a data sample of approximately 124 x 10[sup 6] B[bar B] events collected by the BABAR detector at the PEP-II e[sup +]e[sup -] B-factory. B (B[sup 0] --> D[sub s][sup *+]D[sup *-]) is measured selecting neutral B meson decays to the final state D[sup *-]D[sub s][sup *+] with partial reconstruction of the D[sub s][sup *+], in which only the D[sup *-] and the soft photons from the decay D[sub s][sup *+] --> D[sub s][sup +][gamma] are reconstructed. The branching fraction product B (B[sup 0] --> D[sub s][sup *+]D[sup *-]) [center-dot] B(D[sub s][sup +] --> [phi][pi][sup +]) is measured via a complete reconstruction of the whole decay chain. Comparing these two measurements provides a model-independent determination of the B (D[sub s][sup +] --> [phi][pi][sup +]) branching fraction. The authors obtain the following preliminary results: B(B[sup 0] --> D[sub s][sup *+]D[sup *-]) = (1.85 [+-] 0.09 [+-] 0.16)%; B(D[sub s][sup +] --> [phi][pi][sup +]) = (4.71 [+-] 0.47 [+-] 0.35)% where the first error in each measurement is statistical, the second systematic.