Measurement of CP-violating parameters in fully reconstructed $B\to D^{(*)}\pi$ and $B\to D\rho$ decays

TL;DR

This paper reports a preliminary measurement of CP-violating asymmetries in specific B meson decays using data from the BaBar detector, providing insights into matter-antimatter asymmetry in the universe.

Contribution

It presents the first measurements of CP-violating parameters in fully reconstructed $B o D^{(*)} ho$ decays with detailed statistical and systematic analysis.

Findings

Measured CP-violating parameters with statistical and systematic uncertainties.

Found asymmetry parameters consistent with Standard Model expectations.

Provided data to constrain CKM matrix elements.

Abstract

We present a preliminary measurement of CP-violating asymmetries in fully reconstructed $B^0{\to}D^{(*)\pm}\pi^{\mp}$ and $\B^0{\to}D^{\pm}\rho^{\mp}$ decays in approximately 110 million $\Upsilon(\rm 4S) \to B\bar{B}$ decays collected with the BaBar detector at the PEP-II asymmetric-energy $B$ factory at SLAC. % From a maximum likelihood fit to the time-dependent decay distributions we obtain for the CP-violating parameters: $a^{D\pi} = -0.032\pm0.031 (\textrm{stat.})\pm 0.020 (\textrm{syst.}), c_{\rm lep}^{D\pi} = -0.059\pm0.055 (\textrm{stat.})\pm 0.033 (\textrm{syst.})$ on the $B^0{\to}D^{\pm}\pi^{\mp}$ sample, $a^{D^*\pi} = -0.049\pm0.031 (\textrm{stat.})\pm 0.020 (\textrm{syst.}), c_{\rm lep}^{D^*\pi} = +0.044\pm0.054 (\textrm{stat.})\pm 0.033 (\textrm{syst.})$ on the $B^0{\to}D^{*\pm}\pi^{\mp}$ sample, and $a^{D\rho} = -0.005\pm0.044 (\textrm{stat.})\pm 0.021 (\textrm{syst.}), c_{\rm lep}^{D\rho} = -0.147\pm0.074 (\textrm{stat.})\pm 0.035 (\textrm{syst.})$ on the $B^0{\to}D^{\pm}\rho^{\mp}$ sample.