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arXiv · 1503.04581

Impact of heavy-flavour production cross sections measured by the LHCb experiment on parton distribution functions at low x

Oleksandr Zenaiev·Achim Geiser·Katerina Lipka·Johannes Blümlein·Amanda Cooper-Sarkar·Maria-Vittoria Garzelli·Marco Guzzi·Oleg Kuprash·Sven-Olaf Moch·Pavel Nadolsky·Ringaile Placakyte·Klaus Rabbertz·Ingo Schienbein·Pavel Starovoitov
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Abstract

The impact of recent measurements of heavy-flavour production in deep inelastic $ep$ scattering and in $pp$ collisions on parton distribution functions is studied in a QCD analysis in the fixed-flavour number scheme at next-to-leading order. Differential cross sections of charm- and beauty-hadron production measured by LHCb are used together with inclusive and heavy-flavour production cross sections in deep inelastic scattering at HERA. The heavy-flavour data of the LHCb experiment impose additional constraints on the gluon and the sea-quark distributions at low partonic fractions $x$ of the proton momentum, down to $x \sim 5 \times 10^{-6}$. This kinematic range is currently not covered by other experimental data in perturbative QCD fits.

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Oleksandr Zenaiev, Achim Geiser, Katerina Lipka, Johannes Blümlein, Amanda Cooper-Sarkar, Maria-Vittoria Garzelli, Marco Guzzi, Oleg Kuprash, Sven-Olaf Moch, Pavel Nadolsky, Ringaile Placakyte, Klaus Rabbertz, Ingo Schienbein, Pavel Starovoitov. 2015-03-16. Impact of heavy-flavour production cross sections measured by the LHCb experiment on parton distribution functions at low x. https://doi.org/10.1140/epjc%2Fs10052-015-3618-z

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