Intrinsic charm and $D^{+}{D}^{-}$ asymmetry produced in proton-proton collisions

Abstract

We investigate the contribution of the charm-anticharrm ($c\bar{c}$) asymmetry of the proton eigenstate obtained from QCD lattice gauge to the asymmetry of $D^{+}{D}^{-}$ and $D^0{\bar{D}}^0$ mesons produced in $pp$ collisions at large Feynman variables $x$. It is shown that an important tool for the establishing the intrinsic charm (IC) content of the proton is the charm hadron-antihadron asymmetry formed in $pp$ collisions. Predictions for the asymmetry as function of $x$ for different IC probabilities are presented. We show that the interference of the intrinsic $|uudc\bar{c}>$ Fock state with the standard contribution from the PQCD evolution leads to a large $D^{+}{D}^{-}$ asymmetry at large Feynman $x$.

Comments: 17 pages, 13 figures