Dalitz Plot Analysis of B- --> D+ pi- pi-

TL;DR

This paper presents a detailed Dalitz plot analysis of B- decays to D+ pi- pi-, measuring branching fractions, confirming known resonances, and determining masses and widths of D* states with high precision.

Contribution

It provides the first comprehensive Dalitz plot analysis of B- --> D+ pi- pi- decays, including measurements of resonance parameters and confirmation of D*0_0 existence.

Findings

Measured the inclusive branching fraction as (1.08 ± 0.03 ± 0.05) x 10^{-3}.

Confirmed the existence of D*0_0 resonance.

Determined masses and widths of D*0_2 and D*0_0 states.

Abstract

We present a Dalitz plot analysis of B- --> D+ pi- pi- decays, based on a sample of about 383 million Y(4S) --> BBbar decays collected by the BaBar detector at the PEP-II asymmetric-energy B Factory at SLAC. The analysis has been published previously in PRD. We measure the inclusive branching fraction of the three-body decay to be BR(B- --> D+ pi- pi-) = (1.08 \pm 0.03\stat \pm 0.05\syst) x 10^{-3}$. We observe the established D^{*0}_2 and confirm the existence of D^{*0}_0 in their decays to D+ pi-, where the D^{*0}_2 and D^{*0}_0 are the 2+ and 0+ c-ubar P-wave states, respectively. We measure the masses and widths of D^{*0}_2 and D^{*0}_0 to be: m_{D^{*}_2} = (2460.4 \pm 1.2 \pm 1.2 \pm 1.9) MeV/c^2, Gamma_{D^*_2} = (41.8 \pm 2.5 \pm 2.1 \pm 2.0) MeV, m_{D^{*}_0} = (2297 \pm 8 \pm 5 \pm 19) MeV/c^2, Gamma_{D^*_0} = (273 \pm 12 \pm 17 \pm 45) MeV. The stated errors reflect the statistical and systematic uncertainties, and the uncertainty related to the assumed composition of signal events and the theoretical model.