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arXiv · 1902.09735

Mesons with Beauty and Charm: New Horizons in Spectroscopy

Estia J. Eichten·Chris Quigg
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Abstract

The $B_c ^+$ family of $(c\bar{b})$ mesons with beauty and charm is of special interest among heavy quarkonium systems. The $B_c ^+$ mesons are intermediate between $(c\bar{c})$ and $(b\bar{b})$ states both in mass and size, so many features of the $(c\bar{b})$ spectrum can be inferred from what we know of the charmonium and bottomonium systems. The unequal quark masses mean that the dynamics may be richer than a simple interpolation would imply, in part because the charmed quark moves faster in $B_c$ than in the $J/\psi$. Close examination of the $B_c ^+$ spectrum can test our understanding of the interactions between heavy quarks and antiquarks and may reveal where approximations break down. ...

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Estia J. Eichten, Chris Quigg. 2019-02-26. Mesons with Beauty and Charm: New Horizons in Spectroscopy. https://doi.org/10.1103/physrevd.99.054025

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