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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').

16 results found.

  1. GRB 100823A: optical upper limit
  2. GRB 100823A: optical observations
  3. GRB 100823A: MAXI/GSC detection
  4. GRB 100823A: Swift/UVOT Evidence for Fading Afterglow Emission
  5. GRB100823A : MOA optical observation
  6. GRB 100823A: Candidate IR afterglow
  7. GRB 100823A: Swift XRT refined analysis
  8. GRB 100823A: VLT/X-Shooter spectroscopy
  9. GRB 100823A - second epoch WHT observations
  10. GRB 100823A: TNG NIR observations
  11. GRB 100823: 1.5m OSN I-band observations
  12. GRB 100823A: Swift/UVOT Upper Limits
  13. GRB 100823A: WHT observations
  14. GRB 100823A: Swift-BAT refined analysis
  15. GRB 100823A: Enhanced Swift-XRT position
  16. GRB 100823A: Swift detection of a burst


Download all Circulars as a .tar.gz archive:
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