Kaon production in Au+Au collisions at 11.6A GeV/c

Citation
L. Ahle et al., Kaon production in Au+Au collisions at 11.6A GeV/c, PHYS REV C, 58(6), 1998, pp. 3523-3538
Citations number
28
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Physics
Journal title
PHYSICAL REVIEW C-NUCLEAR PHYSICS
ISSN journal
0556-2813 → ACNP
Volume
58
Issue
6
Year of publication
1998
Pages
3523 - 3538
Database
ISI
SICI code
0556-2813(199812)58:6<3523:KPIACA>2.0.ZU;2-R
Abstract
A systematic study of the spectra and yields of K+ and K- is reported by ex periment E866 as a function of centrality in Au+Au collisions at 11.6A GeV/ c. The invariant transverse spectra for both kaon species are well describe d by exponentials in m(t), with inverse slope parameters that are largest a t midrapidity and which increase with centrality. The inverse slopes of the K+ spectra are slightly larger than the inverse slopes of the K- spectra. The kaon rapidity density peaks at midrapidity with the K+ distribution wid er in rapidity than K-. The integrated total yields of K+ and K- increase n onlinearly and steadily with the number of projectile participants. The yie ld per participant for kaons is two to three times larger than the yield fr om N-N collisions. This enhancement suggests that the majority of kaons in central Au+Au reactions are produced in secondary hadronic collisions. Ther e is no evidence for an onset of additional kaon production from a possible small volume of baryon-rich quark-gluon plasma. The differences between K and K- rapidity distributions and transverse spectra are consistent with a lower phase space for K- production due to a higher energy threshold. Thes e differences also exclude simple thermal models that assume emission from a common equilibrated system. [S0556-2813(98)01011-5].