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تسجيل مستخدم جديدUnderstanding the $K^*/K$ ratio in heavy ion collisions
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We study the $K^*$ meson dissociation in heavy ion collisions during the hadron gas phase. We use the production and absorption cross sections of the $K^*$ and $K$ mesons in a hadron gas, which were calculated in a previous work. We compute the time evolution of the $K^*$ abundance and the $K^* /K$ ratio during the hadron gas phase. Assuming a Bjorken type cooling and using an empirical relation between the freeze-out temperature and the central multiplicity density, we are able to write $K^* /K$ as a function of ($ dN /d eta (eta =0)$). The obtained function is in very good agreement with recent experimental data.
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