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On the future of Gamma-Ray Burst Cosmology

E. Mortsell·J. Sollerman
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Abstract

With the understanding that the enigmatic Gamma-Ray Burts (GRBs) are beamed explosions, and with the recently discovered ``Ghirlanda-relation'', the dream of using GRBs as cosmological yardsticks may have come a few steps closer to reality. Assuming the Ghirlanda-relation is real, we have investigated possible constraints on cosmological parameters using a simulated future sample of a large number of GRBs inspired by the ongoing SWIFT mission. Comparing with constraints from a future sample of Type Ia supernovae, we find that GRBs are not efficient in constraining the amount of dark energy or its equation of state. The main reason for this is that very few bursts are available at low redshifts.

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E. Mortsell, J. Sollerman. 2005-06-14. On the future of Gamma-Ray Burst Cosmology. https://doi.org/10.1088/1475-7516%2F2005%2F06%2F009

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