Measurement of BR(B0 -> Ds*+D*-) and Determination of the Ds+ -> phi pi+ Branching Fraction with a Partial-Reconstruction Method
Abstract
We present model-independent measurements of the branching fractions
B(
B
0
→
D
∗+
s
D
∗−
)
and
B(
D
+
s
→ϕ
π
+
)
based on 19.3 $\textup{fb}^{-1}$ of data collected by the
BABAR
detector at the PEP-II
e
+
e
−
B
Factory. Neutral
B
-meson decays to the
D
∗+
s
D
∗−
final state are selected with a partial reconstruction of the
D
∗+
s
; that is, only the
D
∗−
and the soft photon from the decay $D_s^{*+} \to \Ds \gamma$ are reconstructed. The branching fraction
B(
B
0
→
D
∗+
s
D
∗−
)
is extracted from these event yields, while
B(
D
+
s
→ϕ
π
+
)
is determined by combining this result with a previous measurement of the product
B(
B
0
→
D
∗+
s
D
∗−
)×B(
D
+
s
→ϕ
π
+
)
with partial reconstruction of the
D
∗−
. We obtain the following preliminary results:
B(
B
0
→
D
∗+
s
D
∗−
)=(1.50±0.16±0.12)
B(
D
+
s
→ϕ
π
+
)=(4.7±0.6±0.8)
where the first error is statistical, and the second systematic.