The Giant Flare of 1998 August 27 from SGR 1900+14. II. Radiative Mechanism and Physical Constraints on the Source

  title={The Giant Flare of 1998 August 27 from SGR 1900+14. II. Radiative Mechanism and Physical Constraints on the Source},
  author={Christopher Thompson and Robert C. Duncan},
  journal={The Astrophysical Journal},
  pages={980 - 1005}
The extraordinary 1998 August 27 giant flare places strong constraints on the physical properties of its source, SGR 1900+14. We make detailed comparisons of the published data with the magnetar model, which identifies the soft gamma repeaters as neutron stars endowed with ~1015 G magnetic fields. The giant flare evolved through three stages, whose radiative mechanisms we address in turn. The extreme peak luminosity L > 106LEdd, hard spectrum, and rapid variability of the initial ~0.5 s spike… 

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