Sub-leading contributions to the intrinsic charm of the nucleon

Detailed balance and sea-quark flavor asymmetry of proton

“…So we neglect them in this study, though there have been suggestions of "intrinsic" strange [3] and charm [11,12] of the proton. We also need to check the applicability for the statistical method to model the structure of the nucleon.…”

Intrinsic charm contribution to the proton spin

“…The size of a possible intrinsic charm contribution in the proton has been the topic of intensive discussions [1,2,3,4] for many years. It is therefore a natural question to investigate the polarized intrinsic charm distribution in the nucleon [5].…”

“…In deriving this expression we used (2,9). Note that the first term in R µ does not contribute to the forward matrix element because of its gradient form, while the contribution of the second one is rewritten, by making use of the equation of motion, as matrix element of the operator…”

“…As the mass term in the triangle diagram is coming from the region of transverse momenta of the order m c , this should be the correct scale of both α s and f (2) S . Because this scale is not far from the typical hadronic scale at which f (2) S was estimated we can neglect evolution effects. Note that this contribution is of non-perturbative origin (therefore we call it intrinsic), so that it is sensitive to large distances, as soon as the factorization scale is larger than m c .…”

Challenges in Heavy Flavor and Quarkonium Production inp + pCollisions at the LHC

“…Hoffman and Moore incorporated mass effects and introduced next-to-leading order corrections as well as scale evolution [67]. They compared their result to the EMC F 2 c data from muon scattering on iron at ν = Q 2 /2m p x = 53, 95, and 168 GeV with the intrinsic charm contribution added to the leading order perturbative calculation of F 2 c .…”