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تسجيل مستخدم جديدOn a possible cosmological evolution of galaxy cluster $Y_{rm X}-Y_{rm SZE}$ scaling relation
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An important result from self-similar models that describe the process of galaxy cluster formation is the simple scaling relation $Y_{rm SZE}D_{rm A}^{2}/C_{rm XSZE}Y_{rm X}= C$. In this ratio, $Y_{rm SZE}$ is the integrated Sunyaev-Zeldovich effect flux of a cluster, its x-ray counterpart is $Y_{rm X}$, $C_{rm XSZE}$ and $C$ are constants and $D_{rm A}$ is the angular diameter distance to the cluster. In this paper, we consider the cosmic distance duality relation validity jointly with type Ia supernovae observations plus $61$ $Y_{rm SZE}D_{rm A}^{2}/C_{rm XSZE}Y_{rm X}$ measurements as reported by the Planck Collaboration to explore if this relation is constant in the redshift range considered ($z<0.5$). No one specific cosmological model is used. As basic result, although the data sets are compatible with no redshift evolution within 2$sigma$ c.l., a Bayesian analysis indicates that other $C(z)$ functions analyzed in this work cannot be discarded. It is worth to stress that the observational determination of an universal $C(z)$ function turns the $Y_{rm SZE}D_{rm A}^{2}/C_{rm XSZE}Y_{rm X}$ ratio in an useful cosmological tool to determine cosmological parameters.
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