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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. See the documentation for help with subscribing to or submitting Circulars.

Search for Circulars by submitter, subject, or body text (e.g. 'Fermi GRB').
To navigate to a specific circular, enter the associated Circular ID (e.g. 'gcn123', 'Circular 123', or '123').

17 results found.

  1. GRB 070724: Closer association with DSS source
  2. GRB 051221: Redshift from Gemini
  3. GRB 051221: Continued fading of optical afterglow
  4. GRB 051221B: BOOTES optical observations.
  5. GRB 051221: Discovery of fading optical afterglow
  6. GRB 051221: Swift XRT refined analysis
  7. GRB 051221: Swift/UVOT upper limits
  8. GRB 051221: Possible nearby cluster
  9. GRB 051221: No variability in Gemini data
  10. GRB 051221: Correction to GCN #4368
  11. GRB 051221: Gemini observations
  12. GRB 051221: Improved astrometry of the IR counterpart
  13. GRB051221: K-band source
  14. GRB 051221: XRT position
  15. GRB 051221: Refined analysis of the Swift-BAT short hard burst
  16. GRB 051221: IR Observations at GRB+1hr
  17. GRB 051221: Swift detection of a bright short burst

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