Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
1836613 | Nuclear Physics A | 2011 | 8 Pages |
PHENIX has studied J/ψ production in collisions of p+p, d+Au, Au+Au and Cu+Cu collisions. This systematic study was designed to allow the extraction of hot nuclear matter effects on J/ψ production in heavy ion collisions after accounting for the baseline production cross section using p+p data, and for cold nuclear matter effects using d+Au data. Cold nuclear matter effects, for example gluon shadowing, are the effects associated with production of J/ψ from a nuclear target. The large yields obtained in the RHIC 2008 d+Au run provide, for the first time, an opportunity to characterize cold nuclear matter effects at RHIC, and try to isolate hot nuclear matter effects in Au+Au collisions. Low statistics preliminary measurements of excited charmonium yields and ϒ(1S+2§+3S) yields exist so far for p+p collisions, and there are preliminary results for ϒ production in d+Au collisions.