Strangeness production in high-energy collisions and Hawking-Unruh radiation

Abstract

The assumption that the production of quark-antiquark pairs and their sequential string-breaking taking place through the event horizon of the color confinement determines freezeout temperature and gives a plausible interpretation of the thermal pattern of pp and AA collisions. When relating the black-hole electric charges to the baryon-chemical potentials it was found that the phenomenologically-deduced parameters from various particle ratios in the statistical thermal models agree well with the ones determined from the thermal radiation from charged black-hole. Accordingly, the resulting freezeout conditions, such as $s/T^3=7$ and $<E>/<N>=1~$GeV, are confirmed at finite chemical potentials, as well. Furthermore, the problematic of strangeness production in elementary collisions can be interpreted by thermal particle production from the Hawking-Unruh radiation. Consequently, the freezeout temperature depends on the quark masses. This leads to a deviation from full equilibrium and thus a suppression of the strangeness production in the elementary collisions. But in nucleus-nucleus collisions, an average temperature should be introduced in order to dilute the quark masses. This nearly removes the strangeness suppression. An extension to finite chemical potentials is introduced. The particle ratios of kaon-to-pion, phi-to-kaon and antilambda-to-pion are determined from Hawking-Unruh radiation and compared with the thermal calculations and the measurements in different experiments. We conclude that these particle ratios can be reproduced, at least qualitatively, as Hawking-Unruh radiation at finite chemical potential. With increasing energy, both K+/pi+ and phi/K^- keep their maximum values at low SPS energies. But the further energy decrease rapidly reduces both ratios. For Lambda/pi-, there is an increase with increasing collision energy, i.e. no saturation is to be observed.