Leading charm in hadron-nucleus interactions in the intrinsic charm model

Abstract

Leading charm hadrons produced in hadron-nucleus interactions cannot be adequately described within the parton fusion model. Recent results on charm baryon production in Σ − A interactions at 330 GeV with the WA89 detector disagree with fusion predictions. Intrinsic heavy quark pairs in the Σ − (dds) wavefunction provide a simple mechanism for producing fast charm hadrons. We calculate leading charm baryon production from Σ − , π

Asymmetries between strange and antistrange particle production in pion–proton interactions

“…[19] to strangeness production. We describe how we calculate strangeness production at leading twist in Section 2.…”

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

“…Open charm observables in hadroproduction include forward Λ c production at the ISR [59] and asymmetries between leading and nonleading charm (D mesons which share valence quarks with the projectile and D mesons which do not, respectively) measured as functions of x F and p T in fixed-target experiments, WA89 and WA82 at CERN; E791 and SELEX at Fermilab, see Refs. [60][61][62] and references therein. In addition, the NA3 collaboration measured double J/ψ production at forward x F in πA interactions, difficult to explain without an intrinsic charm mechanism [63].…”

Ξ− and distributions in hadron–nucleus interactions

“…Hyperon parton distributions can be inferred from the proton distributions [27] by simple counting rules. We can relate the valence s distribution of the Σ − , f Σ − sv , to the proton valence d distribution, f p dv , and the valence d distribution in the Σ − , f Σ − dv , to the valence u in the proton, f p uv , so that…”

“…We assume that the relative A dependence for leading-twist and intrinsic production is the same as that for heavy quarks and quarkonia [25,27,31,36]. The A dependence of the two component model is…”

“…We employ the intrinsic model [23,24,25,26,27] as developed for strangeness pro-duction in Ref. [28].…”