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تسجيل مستخدم جديدFirst evidence for different freeze-out conditions for kaons and antikaons observed in heavy-ion collisions
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Differential production cross sections of K- and K+ mesons have been measured in Ni+Ni and Au+Au collisions at a beam energy of 1.5 AGeV. The K-/K+ ratio is found to be nearly constant as a function of the collision centrality and system size. The spectral slopes and the polar emission pattern differ for K- and K+ mesons. These observations indicate that K+ mesons decouple earlier from the fireball than K- mesons.
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We study chemical freeze-out parameters for heavy-ion collisions by performing two different thermal analyses. We analyze results from thermal fits for particle yields, as well as, net-charge fluctuations in order to characterize the chemical freeze-
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Relative hadron abundances from high-energy heavy-ion collisions reveal substantial inhomogeneities of temperature and baryon-chemical potential within the decoupling volume. The freeze-out volume is not perfectly stirred, i.e. the concentrations of
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