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تسجيل مستخدم جديدTsallis Statistics in High Energy Physics: Chemical and Thermal Freeze-Outs
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We present an overview of a proposal in relativistic proton-proton ($pp$) collisions emphasizing the thermal or kinetic freeze-out stage in the framework of the Tsallis distribution. In this paper we take into account the chemical potential present in the Tsallis distribution by following a two step procedure. In the first step we used the redundancy present in the variables such as the system temperature, $T$, volume, $V$, Tsallis exponent, $q$, chemical potential, $mu$, and performed all fits by effectively setting to zero the chemical potential. In the second step the value $q$ is kept fixed at the value determined in the first step. This way the complete set of variables $T, q, V$ and $mu$ can be determined. The final results show a weak energy dependence in $pp$ collisions at the centre-of-mass energy $sqrt{s}= 6$ GeV to 13 TeV. The chemical potential $mu$ at kinetic freeze-out shows an increase with beam energy. This simplifies the description of the thermal freeze-out stage in $pp$ collisions as the values of $T$ and of the freeze-out radius $R$ vary only mildly over a wide range of beam energies.
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