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arXiv · 1712.05800

The Hubble constant from SN Refsdal

J. Vega-Ferrero·J. M. Diego·V. Miranda·G. M. Bernstein
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Abstract

Hubble Space Telescope observations from December 11 2015 detected the expected fifth counter image of SN Refsdal at $z = 1.49$. In this letter, we compare the time delay predictions from numerous models with the measured value derived by \citet{Kelly2016a} from very early data in the light curve of the SN Refsdal, and find a best value for $H_0 = 64^{+9}_{-11}~\mathrm{km~s^{-1}~Mpc^{-1}}$ (68\% CL), in excellent agreement with predictions from CMB and recent weak lensing data + BAO + BBN (from the DES Collaboration). This is the first constraint on $H_0$ derived from time delays between multiple lensed SN images, and the first with a galaxy cluster lens, so subject to systematic effects different from other time-delay $H_0$ estimates. Additional time delay measurements from new multiply-imaged SNe will allow derivation of competitive constraints on $H_0$.

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J. Vega-Ferrero, J. M. Diego, V. Miranda, G. M. Bernstein. 2017-12-15. The Hubble constant from SN Refsdal. https://doi.org/10.3847/2041-8213%2Faaa95f

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