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arXiv · 1505.02429

Beauty-quark and charm-quark pair production asymmetries at LHCb

Rhorry Gauld·Ulrich Haisch·Ben D. Pecjak·Emanuele Re
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Abstract

The LHCb collaboration has recently performed a first measurement of the angular production asymmetry in the distribution of beauty quarks and anti-quarks at a hadron collider. We calculate the corresponding standard model prediction for this asymmetry at fixed-order in perturbation theory. Our results show good agreement with the data, which is provided differentially for three bins in the invariant mass of the $b \bar b$ system. We also present similar predictions for both beauty-quark and charm-quark final states within the LHCb acceptance for a collision energy of $\sqrt{s} = 13 \, {\rm TeV}$. We finally point out that a measurement of the ratio of the $b \bar b$ and $c \bar c$ cross sections may be useful for experimentally validating charm-tagging efficiencies.

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Rhorry Gauld, Ulrich Haisch, Ben D. Pecjak, Emanuele Re. 2015-05-10. Beauty-quark and charm-quark pair production asymmetries at LHCb. https://doi.org/10.1103/physrevd.92.034007

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