Heavy-Quarkonium Production in High Energy Proton-Proton Collisions at RHIC.
Author | : |
Publisher | : |
Total Pages | : 4 |
Release | : 2009 |
ISBN-10 | : OCLC:893840669 |
ISBN-13 | : |
Rating | : 4/5 ( Downloads) |
Download or read book Heavy-Quarkonium Production in High Energy Proton-Proton Collisions at RHIC. written by and published by . This book was released on 2009 with total page 4 pages. Available in PDF, EPUB and Kindle. Book excerpt: We update the study of the total [psi] and [Upsilon] production cross section in proton-proton collisions at RHIC energies using the QCD-based Color-Singlet (CS) Model, including next-to-leading order partonic matrix elements. We also include charm-quark initiated processes which appear at leading order in [alpha]{sub s}, but which have so far been overlooked in such studies. Contrary to earlier claims, we show that the CS yield is consistent with measurements over a broad range of J/[psi] rapidities. We also find that charm-quark initiated processes, including both intrinsic and sea-like charm components, typically contribute at least 20 % of the direct J/[psi] yield, improving the agreement with data both for the integrated cross section and its rapidity dependence. The key signature for such processes is the observation of a charm-quark jet opposite in azimuthal angle [phi] to the detected J/[psi]. Our results have impact on the proper interpretation of heavy-quarkonium production in heavy-ion collisions and its use as a probe for the quark-gluon plasma.