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Open Charm and Beauty Production at HERA

Felix Sefkow
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Abstract

Selected new results from the H1 and ZEUS collaborations on $ep$ interactions at 300 - 318 GeV centre-of-mass energy are presented. The full pre-upgrade integrated luminosity of HERA of 110 pb$^{-1}$ is used. Charm cross sections are measured up to high values of $x_B$ and $Q^2$ and are found to be well described by NLO QCD in the 3 flavour scheme. Orbitally excited $D$ mesons are observed; radial excitations are searched for, but are not seen. The first $b$ cross section measurement is confirmed with a lifetime based method, establishing the excess over NLO QCD.

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Felix Sefkow. 2000-11-10. Open Charm and Beauty Production at HERA. https://arxiv.org/abs/hep-ex/0011034

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