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arXiv · 1409.3567

Cosmological Parameters From Supernovae Associated With Gamma-ray Bursts

Abstract

We report estimates of the cosmological parameters $Ω_m$ and $Ω_Λ$ obtained using supernovae (SNe) associated with gamma-ray bursts (GRBs) at redshifts up to 0.606. Eight high-fidelity GRB-SNe with well-sampled light curves across the peak are used. We correct their peak magnitudes for a luminosity-decline rate relation to turn them into accurate standard candles with dispersion $σ= 0.18$ mag. We also estimate the peculiar velocity of the low-redshift host galaxy of SN 1998bw, using constrained cosmological simulations. In a flat universe, the resulting Hubble diagram leads to best-fit cosmological parameters of $(Ω_m, Ω_Λ) = (0.58^{+0.22}_{-0.25},0.42 ^{+0.25}_{-0.22})$. This exploratory study suggests that GRB-SNe can potentially be used as standardizable candles to high redshifts to measure distances in the universe and constrain cosmological parameters.

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Xue Li, Jens Hjorth, Radosław Wojtak. 2014-10-15. Cosmological Parameters From Supernovae Associated With Gamma-ray Bursts. https://doi.org/10.1088/2041-8205%2F796%2F1%2Fl4

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