# Measurements of time-dependent CP asymmetries in $B \\to D^{\*\\mp} \\pi^{\\pm}$ decays using a partial reconstruction technique

Source: [Measurements of time-dependent CP asymmetries in $B \\to D^{\*\\mp} \\pi^{\\pm}$ decays using a partial reconstruction technique](<https://www.sota2.com/research/paper/68fa3a381e209131ce8c8f4e>)

Collection index: [llms.txt](<https://www.sota2.com/research/llms.txt>)

Data updated: 2025-10-24T23:56:34.920Z

Authors: S. Bahinipati, K. Trabelsi, K. Kinoshita

Published: 2011-02-04T11:55:25.000Z

## Abstract

We report results on time-dependent CP asymmetries in $B \\to D^{\*\\mp}\\pi^{\\pm}$ decays based on a data sample containing 657 {\\times} $10^6$ $B\\bar{B}$ pairs collected with the Belle detector at the KEKB asymmetric-energy $e^+ e^-$ collider at the $\\Upsilon(4S)$ resonance. We use a partial reconstruction technique, wherein signal $B \\to D^{\*\\mp}\\pi^{\\pm}$ events are identified using information only from the fast pion from the B decay and the slow pion from the subsequent decay of the $D^{\*\\mp}$, where the former (latter) corresponds to $D^{\*+} (D^{\*-})$ final states. We obtain CP violation parameters $S^+ = +0.061 \\pm 0.018(\\mathrm{stat}) \\pm 0.012(\\mathrm{syst})$ and $S^- = +0.031 \\pm 0.019(\\mathrm{stat}) \\pm 0.015(\\mathrm{syst})$.

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## Original sources and implementation

[Original paper](<https://arxiv.org/abs/1102.0888>)

[PDF](<https://arxiv.org/pdf/1102.0888.pdf>)