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arXiv · 1501.01646

Predicting positive parity $B_{s}$ mesons from lattice QCD

C. B. Lang·Daniel Mohler·Sasa Prelovsek·R. M. Woloshyn
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Abstract

We determine the spectrum of $B_s$ 1P states using lattice QCD. For the $B_{s1}(5830)$ and $B_{s2}^*(5840)$ mesons, the results are in good agreement with the experimental values. Two further mesons are expected in the quantum channels $J^P=0^+$ and $1^+$ near the $BK$ and $B^{*}K$ thresholds. A combination of quark-antiquark and $B^{(*)}$ meson-Kaon interpolating fields are used to determine the mass of two QCD bound states below the $B^{(*)}K$ threshold, with the assumption that mixing with $B_s^{(*)}η$ and isospin-violating decays to $B_s^{(*)}π$ are negligible. We predict a $J^P=0^+$ bound state $B_{s0}$ with mass $m_{B_{s0}}=5.711(13)(19)$ GeV. With further assumptions motivated theoretically by the heavy quark limit, a bound state with $m_{B_{s1}}= 5.750(17)(19)$ GeV is predicted in the $J^P=1^+$ channel. The results from our first principles calculation are compared to previous model-based estimates.

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C. B. Lang, Daniel Mohler, Sasa Prelovsek, R. M. Woloshyn. 2015-09-04. Predicting positive parity $B_{s}$ mesons from lattice QCD. https://doi.org/10.1016/j.physletb.2015.08.038

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