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arXiv · 2408.02126

Highly excited $B$, $B_s$ and $B_c$ meson spectroscopy from lattice QCD

Luke Gayer·Sinéad M. Ryan·David J. Wilson
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Abstract

Excited state spectra of $B$, $B_s$ and $B_c$ mesons are computed using lattice QCD. Working with a large basis of carefully constructed, approximately-local $q\bar{q}$-like operators we determine a rich spectrum of states up to $J=4$ in $B, B_s$ and $B_c$, that can be grouped into patterns matching those of the quark model. In addition, hybrid-like states are identified at approximately 1500 MeV above the ground states in each of $B, B_s$ and $B_c$, in a multiplet pattern already found in similar computations at a range of quark masses spanning light to bottom. This study is performed using an anisotropic, relativistic Wilson-clover action at a single spatial lattice spacing of $a_s\approx 0.12$ fm and with a light-quark mass corresponding to $m_\pi\approx 391$ MeV. We find good agreement with experimental results where known and discuss prospects for further work in interesting $J^P$ quantum numbers.

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Luke Gayer, Sinéad M. Ryan, David J. Wilson. 2024-08-04. Highly excited $B$, $B_s$ and $B_c$ meson spectroscopy from lattice QCD. https://doi.org/10.1007/jhep01(2025)123

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