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arXiv · 0809.1103

Excitations of single-beauty hadrons

Tommy Burch·Christian Hagen·Christian B. Lang·Markus Limmer·Andreas Schäfer
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Abstract

In this work we study the predominantly orbital and radial excitations of hadrons containing a single heavy quark. We present meson and baryon mass splittings and ratios of meson decay constants (e.g., $f_{B_s}/f_B$ and $f_{B_s'}/f_{B_s}$) resulting from quenched and dynamical two-flavor configurations. Light quarks are simulated using the chirally improved (CI) lattice Dirac operator at valence masses as light as $M_π\approx 350$ MeV. The heavy quark is approximated by a static propagator, appropriate for the $b$ quark on our lattices ($1/a \sim 1-2$ GeV). We also include some preliminary calculations of the $O(1/m_Q^{})$ kinetic corrections to the states, showing, in the process, a viable way of applying the variational method to three-point functions involving excited states. We compare our results with recent experimental findings.

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Tommy Burch, Christian Hagen, Christian B. Lang, Markus Limmer, Andreas Schäfer. 2008-12-18. Excitations of single-beauty hadrons. https://doi.org/10.1103/physrevd.79.014504

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