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arXiv · hep-ph/9707387

HERA Anomaly and Hard Charm in the Nucleon

W. Melnitchouk·A. W. Thomas
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Abstract

We explore the possibility that the excess neutral and charged current events seen by the H1 and ZEUS Collaborations at HERA at large x and Q^2 could arise from a hard charm component of the nucleon. While the symmetric intrinsic charm hypothesis is unable to account for the HERA anomaly, a non-symmetric charm distribution generated non-perturbatively, for which c-bar is much harder than c, can produce significant enhancement of cross sections at the HERA kinematics.

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W. Melnitchouk, A. W. Thomas. 1997-09-15. HERA Anomaly and Hard Charm in the Nucleon. https://doi.org/10.1016/s0370-2693(97)01150-7

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