Search for B+ -> D*+ pi0 decay

TL;DR

This paper reports a search for a rare B+ meson decay to D*+ pi0, finds no significant signal, and sets an upper limit on its branching ratio, helping constrain decay amplitude ratios.

Contribution

First search for the doubly Cabibbo suppressed B+ -> D*+ pi0 decay, establishing an upper limit on its branching ratio and constraining decay amplitude ratios.

Findings

No significant signal detected.

Upper limit on Br(B+ -> D*+ pi0) < 3.6 x 10^-6.

Constraint on amplitude ratio r < 0.051.

Abstract

We report on a search for the doubly Cabibbo suppressed decay B+ -> D*+ pi0, based on a data sample of 657 million BBbar pairs collected at the Upsilon(4S) resonance with the Belle detector at the KEKB asymmetric energy e+ e- collider. We find no significant signal and set an upper limit of Br(B+ -> D*+ pi0) < 3.6 x 10^-6 at the 90% confidence level. This limit can be used to constrain the ratio between suppressed and favored B -> D* pi decay amplitudes, r < 0.051, at the 90% confidence level.