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arXiv · 1510.07240

Constraints on a possible variation of the fine structure constant from galaxy cluster data

R. F. L. Holanda·S. J. Landau·J. S. Alcaniz·I. E. Sanchez G.·V. C. Busti
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Abstract

We propose a new method to probe a possible time evolution of the fine structure constant $\alpha$ from X-ray and Sunyaev-Zeldovich measurements of the gas mass fraction ($f_{gas}$) in galaxy clusters. Taking into account a direct relation between variations of $\alpha$ and violations of the distance-duality relation, we discuss constraints on $\alpha$ for a class of dilaton runaway models. Although not yet competitive with bounds from high-$z$ quasar absorption systems, our constraints, considering a sample of 29 measurements of $f_{gas}$, in the redshift interval $0.14 < z < 0.89$, provide an independent estimate of $\alpha$ variation at low and intermediate redshifts. Furthermore, current and planned surveys will provide a larger amount of data and thus allow to improve the limits on $\alpha$ variation obtained in the present analysis.

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R. F. L. Holanda, S. J. Landau, J. S. Alcaniz, I. E. Sanchez G., V. C. Busti. 2015-10-25. Constraints on a possible variation of the fine structure constant from galaxy cluster data. https://doi.org/10.1088/1475-7516%2F2016%2F05%2F047

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