Vitayard OCT.2013 | Page 11

http://vitayard.in Open Science and Research Project OKFN, India Intrinsic Charm Parton Distribution Functions from CTEQ-TEA Global Analysis Sayipjamal Dulat, Tie-Jiun Hou, Jun Gao, Joey Huston, Jon Pumplin, Carl Schmidt, Daniel Stump, C.-P. Yuan Description: We study the possibility of intrinsic (nonperturbative) charm in parton distribution functions (PDF) of the proton, within the context of the CT10 next-to-next-to-leading order (NNLO) global analysis. Three models for the intrinsic charm (IC) quark content are compared: (i) $\hat{c}(x) = 0$ (zero-IC model); (ii) $\hat{c} (x)$ is parametrized by a valence-like parton distribution (BHPS model); (iii) $\hat{c}(x)$ is parametrized by a sea-like parton distribution (SEA model). In these models, the intrinsic charm content, $\hat{c}(x)$, is included in the charm PDF at the matching scale $Q_c=m_c=1.3$ GeV. The best fits to data are constructed and compared. Correlations between the value of $m_c$ and the amount of IC are also considered. Cite as: arXiv:1309.0025 [hep-ph] (or arXiv:1309.0025v1 [hep-ph] for this version) 11