Search for the Decay B0 --> rho0rho0

TL;DR

This paper reports a search for the B0 --> rho0 rho0 decay mode using data from the BABAR detector, setting an upper limit on its branching fraction and discussing implications for CKM angle alpha.

Contribution

First search for B0 --> rho0 rho0 decay with a large data sample, providing new upper limits and insights into penguin contributions and CKM angle constraints.

Findings

No significant signal observed.

Upper limit of 1.1 x 10^-6 on branching fraction.

Implications for penguin contributions and CKM angle alpha.

Abstract

The B --> rho0 rho0 decay mode is searched for in a data sample of about 227 million Upsilon(4S) --> B Bbar decays collected with the BABAR detector at the PEP-II asymmetric B factory at SLAC. No significant signal is observed, and an upper limit of 1.1 x 10e-6 (90% C.L.) on the branching fraction is set. Implications on the penguin contribution and constraints on the CKM angle alpha with B --> rho rho decays are discussed. All results are preliminary.