Production of strange particles at intermediate pT in central Au+Au collisions at high energies

The recombination model is applied to the production of K,φ,Λ , and Ω at all pT in central Au+Au collisions. The thermal-shower component of the recombination is found to be important for K and Λ, but only in a minor way for φ and Ω in the intermediate to high pT region. The normalization and inverse slope of the thermal partons in the strange sector are determined by fitting the low-pT data. At higher pT the data of K,Λ,φ, and Ω in the log scale are all well reproduced in our study that extends the thermal contribution and includes the shower contribution. The calculated result on the Λ/K ratio rises to a maximum of around 2 at pT≅4 GeV/c, arching over the data in linear scale. The production of φ and Ω are shown to arise mainly from the recombination of thermal partons, thus exhibiting exponential pT dependences in agreement with the data. Their ratio, RΩ/φ, rises linearly to pT≅4 GeV/c and develops a maximum at pT≅5.5 GeV/c. It is argued that the pT spectra of φ and Ω reveal directly the partonic nature of the thermal source that characterizes quark-gluon plasma. Comments are made on the Ω puzzle due to the simultaneous observation of both the exponential behavior of the Ω spectrum in pT and the existence of low-pT particles associated with Ω as trigger