Catalogo Articoli (Spogli Riviste)

OPAC HELP

Titolo:
Charm and strangeness in nuclear reactions at root s <= 19 GeV
Autore:
Kabana, S;
Indirizzi:
Univ Bern, High Energy Phys Lab, CH-3012 Bern, Switzerland Univ Bern Bern Switzerland CH-3012 y Phys Lab, CH-3012 Bern, Switzerland
Titolo Testata:
NEW JOURNAL OF PHYSICS
, volume: 3, anno: 2001,
pagine: 161 - 1621
SICI:
1367-2630(20010820)3:<161:CASINR>2.0.ZU;2-D
Fonte:
ISI
Lingua:
ENG
Soggetto:
ANOMALOUS J/PSI SUPPRESSION; HEAVY-ION COLLISIONS; PB-PB COLLISIONS; QUARK MATTER 99; CERN-SPS; PB+PB COLLISIONS; CENTRALITY DEPENDENCE; PARTICLE-PRODUCTION; 158 GEV/C; K-+/;
Tipo documento:
Article
Natura:
Periodico
Settore Disciplinare:
Physical, Chemical & Earth Sciences
Citazioni:
86
Recensione:
Indirizzi per estratti:
Indirizzo: Kabana, S Univ Bern, High Energy Phys Lab, Sidlerstr 5, CH-3012 Bern, Switzerland Univ Bern Sidlerstr 5 Bern Switzerland CH-3012 ern, Switzerland
Citazione:
S. Kabana, "Charm and strangeness in nuclear reactions at root s <= 19 GeV", NEW J PHYS, 3, 2001, pp. 161-1621

Abstract

We propose to study J/Psi production in relation with open charm production in nuclear reactions. It appears that a suppression of the J/Psi over Drell Yan (DY) ratio has been observed by the CERN experiment NA50 in Pb + Pb collisions at roots = 17 GeV above the initial energy density epsilon similar to 2.3 GeV fm(-3), which was not seen in S + U collisions at roots = 19 GeV at any epsilon. In our view a clear interpretation of these results hasnot been achieved. The same experiment has measured an excess in mu (+)mu (-), which can be interpreted as resulting from D (D) over bar decay. We demonstrate that the suppression of the J/Psi does appear in S + U collisions, as well as in Pb + Pb collisions at a lower epsilon similar to 1 GeV fm(-3), if the J/Psi is normalized to D (D) over bar, instead of DY. This underlines the importance of direct open charm measurements for the interpretation of charmonia suppression. Furthermore we study the dependence of the J/Psi and D (D) over bar on the number of participating nucleons (N-p). The results indicate non-thermal charm production as expected, and J/Psi dissociation which is stronger than the absorption seen in other hadrons. We find that the J/Psi in central Pb + Pb collisions is compatible with dominant production from c (c) over bar pair coalescence out of a hadronizing quark andgluon environment. A significant change in the J/Psi) /D (D) over bar ratio as well as in the number density of kaons is observed simultaneously above the initial energy density epsilon similar to 1 GeV fm(-3), suggesting a change of phase associated with this epsilon.

ASDD Area Sistemi Dipartimentali e Documentali, Università di Bologna, Catalogo delle riviste ed altri periodici
Documento generato il 04/04/20 alle ore 15:34:00