B-meson spectroscopy in HQET at order 1/m

Preprint number: CP3-Origins-2015-9 DNRF90 and DIAS-2015-9
Authors: Fabio Bernardoni (NIC @ DESY), Benoît Blossier (Paris-Sud University), John Bulava (Trinity College Dublin), Michele Della Morte (CP3-Origins & DIAS), Patrick Fritzsch (Humboldt-Universität zu Berlin), Nicolas Garron (Trinity College), Antoine Gérardin (Paris-Sud University), Jochen Heitger (University Muenster), Hubert Simma (DESY), and Georg von Hippel (University of Mainz)
External link: arXiv.org

We present a study of the B spectrum performed in the framework of Heavy Quark Effective Theory expanded to next-to-leading order in 1/m and non-perturbative in the strong coupling. Our analyses have been performed on Nf=2 lattice gauge field ensembles corresponding to three different lattice spacings and a wide range of pion masses. We obtain the Bs-meson mass and hyperfine splittings of the B- and Bs-mesons that are in good agreement with the experimental values and examine the mass difference m_{Bs}-m_B as a further cross-check of our previous estimate of the b-quark mass. We also report on the mass splitting between the first excited state and the ground state in the B and Bs systems.