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تسجيل مستخدم جديدProbing the time variation of fine structure constant using galaxy clusters and quintessence model
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We explore a possible time variation of the fine structure constant ($alpha equiv e^2/hbar c$) using the Sunyaev-Zeldovich effect measurements of galaxy clusters along with their X-ray observations. Specifically, the ratio of the integrated Compto-ionization parameter $Y_{SZ}D_A^2$ and its X-ray counterpart $Y_X$ is used as an observable to constrain the bounds on the variation of $alpha$. Considering the violation of cosmic distance duality relation, this ratio depends on the fine structure constant as $sim alpha^3$. We use the quintessence model to provide the origin of $alpha$ time variation. In order to give a robust test on $alpha$ variation, two galaxy cluster samples, the 61 clusters provided by the Planck collaboration and the 58 clusters detected by the South Pole Telescope, are collected for analysis. Their X-ray observations are given by the XMM-Newton survey. Our results give $zeta=-0.203^{+0.101}_{-0.099}$ for the Planck sample and $zeta=-0.043^{+0.165}_{-0.148}$ for the SPT sample, indicating that $alpha$ is constant with redshift within $3sigma$ and $1sigma$ for the two samples, respectively.
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