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Photonic production of P-wave states of B_c mesons

A. V. Berezhnoy·V. V. Kiselev·A. K. Likhoded
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Abstract

Numerical calculations for the production of $P$-wave levels of $B_c$ quarkonium in $γγ$ collisions are performed in the leading $O(α_s^2α_{em}^2)$ order of perturbation theory. The total cross-section of $P$-wave state production is about 10 \% of that for the $S$-wave levels. The contribution of fragmentation component ($6+6$ diagrams) is low, and the basic contribution is determined by the recombination mechanism ($8$ Feynman diagrams). The gauge invariant term of the $\bar b\to B_c$ fragmentation ($6$ diagrams) quite accurately reproduces the result of the fragmentation model, whereas there is a strong deviation of the $c\to B_c$ fragmentation term from the predictions of the fragmentation model.

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A. V. Berezhnoy, V. V. Kiselev, A. K. Likhoded. 1995-10-06. Photonic production of P-wave states of B_c mesons. https://doi.org/10.1016/0370-2693(96)00562-x

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