On the significance of B-decays to radially excited D

TL;DR

This paper investigates B-decays to radially excited D mesons, estimating decay constants via lattice QCD, and explores testing recent claims of large B to D' transition form factors through specific decay modes.

Contribution

It provides the first lattice QCD calculation of the decay constant for the radially excited D-meson and discusses implications for B-decay processes.

Findings

Decay constant of D' meson: 117(25) MeV.

Updated D-meson decay constants using twisted mass QCD.

Potential to test large B to D' transition form factor claims.

Abstract

We discuss the possibilities of testing the recent claims of a relatively large value of the B --> D' transition form factor through B0--> D' pi+ and B- --> D' pi- decay modes. To estimate the width of the latter we need the decay constant of the radially excited D-meson that we computed in lattice QCD with Nf=2 dynamical flavors and after taking the continuum limit we found f(D')=117(25) MeV. We also provide an update for the values of the D-meson decay constants obtained by using maximally twisted mass QCD.