Dirty Fireballs and Orphan Afterglows: A Tale of Two Transients

  title={Dirty Fireballs and Orphan Afterglows: A Tale of Two Transients},
  author={James E. Rhoads},
  journal={The Astrophysical Journal},
  • J. Rhoads
  • Published 1 January 2003
  • Physics
  • The Astrophysical Journal
Orphan afterglows are transient events that are produced by cosmological fireballs and resemble gamma-ray burst (GRB) afterglows yet are not accompanied by gamma rays. Such transients may be produced by jetlike GRBs observed off-axis and therefore hold great promise as a test of GRB collimation. However, orphans may also be produced by "dirty fireballs," i.e., cosmological fireballs whose ejecta carry too many baryons to produce a GRB. A well-designed orphan afterglow search can distinguish… Expand

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