Momentum dependence of J/ ψ production in proton–nucleus reactions at near-threshold beam energies

摘要

AbstractWe study the inclusiveJ/ψproduction in proton–nucleus collisions in the near-threshold energy region within the spectral function approach for incoherent primary proton–nucleon charmonium production. Our approach takes into account the effect of the nuclearJ/ψmean-field potential on these processes, as well as the elementary final state interaction (FSI) between the outgoing nucleons participating in them. We calculate the momentum dependence of the variousJ/ψobservables (transparency ratio, absolute and relative charmonium yields) as well as the total cross section forJ/ψproduction inpC,pW andpAu interactions at incident proton kinetic energies of 8, 11 and 23 GeV within the different scenarios for theJ/ψin-medium modification. We show that the transparency ratio forJ/ψmesons has an insignificant sensitivity to theJ/ψin-medium mass shift at these energies. On the other hand, our studies demonstrate that the momentum distributions (absolute and relative) for low momentumJ/ψnear-threshold production inpAreactions have distinct sensitivity to theJ/ψin-medium modification. Therefore, the measurement of such observables in the CBM experiment at FAIR in the near-threshold energy domain will allow to study the modification of the charmonium properties in the nuclear medium.]]>