Use and misuse of ChPT in the heavy-light systems
Abstract
We discuss the range of validity of ChPT when applied to the systems of heavy-light mesons. Having in mind the recent experimental evidence according to which the heavy-light scalar and axial states are closer to the ground states than anticipated, we revisited the prediction for the chiral behavior of the B-Bbar mixing amplitude and examined the impact of nearness of the positive parity states. We conclude that the standard ChPT expressions with Nf=3 light flavours are not useful in guiding the extrapolation of hadronic quantities computed on the lattice. Instead those derived in HMChPT with Nf=2, i.e., including only the pion loops, are still adequate as long as they are applied to the pions lighter than 350 MeV, or the quarks lighter than a third of the physical strange quark mass.
Cite
@article{arxiv.0710.3496,
title = {Use and misuse of ChPT in the heavy-light systems},
author = {Damir Becirevic and Svjetlana Fajfer and Jernej Kamenik},
journal= {arXiv preprint arXiv:0710.3496},
year = {2008}
}
Comments
7 pages, contribution to the proceedings of "Lattice 2007"