Naslov
Measurements of φ meson production in relativistic heavy-ion collisions at RHIC

Autori
Abelev, B.I. ; ... ; Planinić, Mirko ; ... ; Poljak, Nikola ; ... ; Zuo, J.X.

Izvornik
Physical review C (0556-2813) 79 (2009); 64903-1

Vrsta, podvrsta i kategorija rada
Radovi u časopisima, članak, znanstveni

Ključne riječi
phi; meson; STAR

Sažetak
We present results for the measurement of ϕ meson production via its charged kaon decay channel ϕ→K+K− in Au+Au collisions at sNN‾‾‾‾√=62.4, 130, and 200 GeV, and in p+p and d+Au collisions at sNN‾‾‾‾√=200 GeV from the STAR experiment at the BNL Relativistic Heavy Ion Collider (RHIC). The midrapidity (∣∣y∣∣<0.5) ϕ meson transverse momentum (pT) spectra in central Au+Au collisions are found to be well described by a single exponential distribution. On the other hand, the pT spectra from p+p, d+Au, and peripheral Au+Au collisions show power-law tails at intermediate and high pT and are described better by Levy distributions. The constant ϕ/K− yield ratio vs beam species, collision centrality, and colliding energy is in contradiction with expectations from models having kaon coalescence as the dominant mechanism for ϕ production at RHIC. The Ω/ϕ yield ratio as a function of pT is consistent with a model based on the recombination of thermal s quarks up to pT~4 GeV/c, but disagrees at higher transverse momenta. The measured nuclear modification factor, RdAu, for the ϕ meson increases above unity at intermediate pT, similar to that for pions and protons, while RAA is suppressed due to the energy loss effect in central Au+Au collisions. Number of constituent quark scaling of both Rcp and v2 for the ϕ meson with respect to other hadrons in Au+Au collisions at sNN‾‾‾‾√=200 GeV at intermediate pT is observed. These observations support quark coalescence as being the dominant mechanism of hadronization in the intermediate pT region at RHIC.

Izvorni jezik
Engleski

Znanstvena područja
Fizika

Napomena
STAR Collaboration.

POVEZANOST RADA