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The Beaming Factor and Other Open Questions In GRB Jets

Tsvi Piran
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Abstract

I review several central open questions concerning GRB Jets. 1) I discuss a new estimates of the beaming correction for the rate of GRBs ~ 75 +- 20. 2) I discuss the universal structured jet (USJ) model and conclude that while jets might be structured they are less likely to be universal. 3) I discuss recent observations of a sideways expansion of a GRB afterglow and compare these with current hydrodynamics simulations of jet evolution. 4) I discuss the implications of resent outliers to the energy-angle relation.

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Tsvi Piran. 2005-03-23. The Beaming Factor and Other Open Questions In GRB Jets. https://doi.org/10.1393/ncc%2Fi2005-10063-y

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