First Observation of B -> D(*) rho', rho' -> omega pi-

TL;DR

This paper reports the first observation of specific B meson decay modes involving D(*) and omega pi- final states, measuring their branching ratios and analyzing the resonance structure of the omega pi- system.

Contribution

It provides the first observation and measurement of B-> D(*) pi+ pi- pi- pi^o decays and identifies a wide 1^- resonance in the omega pi- system, likely the rho(1450) or rho'.

Findings

Branching ratios for B-> D(*) pi+ pi- pi- pi^o decays are measured.

A wide 1^- resonance in the omega pi- system is observed.

Resonance parameters suggest the rho(1450) or rho' as the underlying state.

Abstract

We report on the observation of B-> D(*) pi+ pi- pi- pi^o decays. The branching ratios for D*+ and D*o are (1.72+/-0.14+/-0.24)% and (1.80+/-0.24+/-0.27)%, respectively. Each final state has a D* omega pi- component, with branching ratios (0.29+/-0.03+/-0.04)% and (0.45+/-0.10+/-0.07)% for the D*+ and D*o modes, respectively. We also observe B -> D omega pi- decays. The branching ratios for D+ and Do are (0.28+/-0.05+/-0.04)% and (0.41+/-0.07+/-0.06)%, respectively. A spin parity analysis of the D omega pi- final state prefers a wide 1^- resonance. A fit to the omega pi- mass spectrum finds a central mass of (1349+/-25^{+10}_{-5}) MeV and width of (547+/-86^{+46}_{-45}) MeV. We identify this object as the rho(1450) or the \rho'.