Measurement of the B^0 -> D^*-a_1^+ Branching Fraction with Partially Reconstructed D^*

TL;DR

This paper reports a measurement of the B^0 -> D^*-a_1^+ branching fraction using partial reconstruction techniques on data from the BABAR experiment, providing a precise estimate of the decay probability.

Contribution

It introduces a partial reconstruction method to measure the B^0 -> D^*-a_1^+ branching fraction with high statistical significance.

Findings

Branching fraction measured as (1.20 +/- 0.07(stat) +/- 0.14(syst))%.

Signal yield of approximately 18,400 events.

Utilized data from the BABAR experiment collected in 1999-2000.

Abstract

The B^0 -> D^*-a_1^+ branching fraction has been measured with data collected by the BABAR experiment in 1999 and 2000 corresponding to a total integrated luminosity of 20.6 fb^-1. Signal events have been selected using a partial reconstruction technique, in which only the a_1^+ and the slow pion (pi_s) from the D^*- decay are identified. A signal yield of 18400 +/- 1200 events has been found, corresponding to a preliminary branching fraction of (1.20 +/- 0.07(stat) +/- 0.14 (syst))%.