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arXiv · 1207.1694

Model-independent constraints on the cosmic opacity

R. F. L. Holanda·J. C. Carvalho·J. S. Alcaniz
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Abstract

We use current measurements of the expansion rate $H(z)$ and cosmic background radiation bounds on the spatial curvature of the Universe to impose cosmological model-independent constraints on cosmic opacity. To perform our analyses, we compare opacity-free distance modulus from $H(z)$ data with those from two supernovae Ia compilations: the Union2.1 plus the most distant spectroscopically confirmed SNe Ia (SNe Ia SCP-0401 $z=1.713$) and two Sloan Digital Sky Survey (SDSS) subsamples. The influence of different SNe Ia light-curve fitters (SALT2 and MLCS2K2) on the results is also verified. We find that a completely transparent universe is in agreement with the largest sample in our analysis (Union 2.1 plus SNe Ia SCP-0401). For SDSS sample a such universe it is compatible at $< 1.5σ$ level regardless the SNe Ia light-curve fitting used.

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R. F. L. Holanda, J. C. Carvalho, J. S. Alcaniz. 2014-04-28. Model-independent constraints on the cosmic opacity. https://doi.org/10.1088/1475-7516%2F2013%2F04%2F027

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