Measurement of the Branching Fractions of the Rare Decays B0->Ds(*)+pi-, B0->Ds(*)+rho-, and B0->Ds(*)-K(*)+

TL;DR

This paper measures the branching fractions of rare B0 decays involving D_s(*) mesons and vector mesons, providing evidence for certain decay modes, polarization measurements, and CKM amplitude ratios, with implications for CP violation studies.

Contribution

It presents the first evidence for specific rare decay modes, measures vector meson polarization, and determines CKM amplitude ratios in B0 decays, advancing understanding of flavor physics.

Findings

Evidence for B0->Ds-K*+ decay

Measurement of vector meson polarization in B0 decays

Determination of CKM amplitude ratios r(D(*)pi) and r(D(*)rho)

Abstract

We report the measurement of the branching fractions of the rare decays B0->Ds(*)+pi-, B0->Ds(*)+rho-, and B0->Ds(*)-K(*)+ in a sample of 381 million Y(4S) decays into BBbar pairs collected with the BABAR detector at the PEP-II asymmetric-energy e+e- storage ring. We present evidence for the decay B0->Ds-K*+ and the vector-vector decays B0->Ds*+rho- and B0->Ds*-K*+, as well as the first measurement of the vector meson polarization in these decays. We also determine the ratios of the CKM-suppressed to CKM-favored amplitudes r(D(*)pi) and r(D(*)rho) in decays B0->D(*)pi and B0->D(*)rho, and comment on the prospects for measuring the CP observable sin(2beta+gamma).