Sizing up the Nuclear Glue in J / ψ - production
نویسندگان
چکیده
Nuclear gluon densities are of great importance to the physics of relativistic heavy ion collisions, in particular, in assessing the origin of J/ψ-suppression. We describe our attempts to distinguish various models of the gluonic EMC-effect, using the existing J/ψ-production data in proton-nucleus collisions. We find that no model is capable of explaining all the features of the high precision E772 data although the overall trend suggests this to be more a matter of fine-tuning the models than the presence of new physical effects.
منابع مشابه
High Precision J/ψ and Υ-production data and the Nuclear Glue
We use the high statistics E-772 data on the nuclear dependence of the production of quarkonia (J/ψ and Υ) and dimuons at large transverse momentum (pT ) in p-A collisions to get information about the gluonic EMC effect. We find a satisfactory quantitative agreement of the theoretical predictions with the data although none of the models of the EMC effect we consider could account for the entir...
متن کاملNuclear modification of the J/Psi transverse momentum
Nuclear modification of the J/ψ transverse momentum distributions in high energy pA and AA collisions We evaluate the transverse momentum spectrum of J/ψ (up to semi-hard momenta) in pA and AA collisions taking into account only the initial state effects, but resumming them to all orders in α 2 s A 1/3. In our previous papers we noticed that cold nuclear matter effects alone could not explain t...
متن کامل[Suppression?].
In proton-nucleus and nucleus-nucleus collisions up to central S −U interactions, the P T-dependence of J/ψ production is determined by initial state parton scattering and pre-resonance nuclear absorption (" normal " J/ψ suppression). The " anomalous " J/ψ suppression in P b−P b collisions must reduce the normal P T broadening, since it occurs mainly in the central part of the interaction regio...
متن کاملDifferent Nuclear Dependence of J / ψ and ψ ′ Production in p - A and A - p Collisions ∗
While presently available p-A data observe that the nuclear dependence of J/ψ and ψ production is the same within errors, we show that different nuclear dependence of J/ψ and ψ production in the kinematic region uncovered by the present p-A data can be predicted based on two different nuclear absorption scenarios. It is found that the predicted production ratio σ(ψ)/σ(J/ψ) at positive xF in A-p...
متن کاملJ/ψ production and suppression in nuclear collisions
In terms of a new QCD factorization formula for J/ψ production, we calculate the J/ψ suppression in nuclear collisions by including the multiple scattering between the preJ/ψ partonic states and the nuclear medium. We find agreement with all data on J/ψ suppression in hadron-nucleus and nucleus-nucleus collisions, except a couple of points (the “second drop”) at the highest ET bins of the new N...
متن کامل