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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 210321A: OSN Upper Limit
  2. GRB 210321A: Swift/UVOT Detection
  3. Konus-Wind detection of GRB 210321A
  4. GRB 210321A: DDOTI Position Correction
  5. GRB 210321A: CrAO optical upper limit
  6. GRB 210321A: Swift-BAT refined analysis
  7. GRB 210321A: Mondy optical observations
  8. GRB 210321A: Xinglong GWAC-F60A optical observation
  9. GRB 210321A: Swift-XRT refined Analysis
  10. GRB 210321A: Redshift from OSIRIS/GTC
  11. GRB 210321A: NOT optical afterglow detection and redshift limit
  12. GRB 210321A: MASTER optical observation
  13. GRB 210321A: Enhanced Swift-XRT position
  14. GRB 210321A: DDOTI Afterglow Confirmation
  15. GRB 210321A: Swift/UVOT Detection
  16. GRB 210321A: Swift-XRT observations
  17. GRB 210321A: Swift detection of a burst


Download all Circulars as a .tar.gz archive:
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