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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').

15 results found.

  1. GRB 221009A: COATLI Detection of the Afterglow
  2. GRB 2209030A: MITSuME Akeno optical upper limits
  3. GRB 220930A: AbAO Optical Upper Limit
  4. Konus-Wind detection of GRB 220930A
  5. GRB 220930A: AstroSat CZTI detection
  6. GRB 220930A: Swift-BAT refined analysis
  7. GRB 220930A: Swift-XRT refined Analysis
  8. GRB 220930A: LCOGT Optical Upper Limits
  9. GRB 220930A: Swift/UVOT Upper Limits
  10. GRB 220930A: Enhanced Swift-XRT position
  11. Swift GRB 220930A: Global MASTER-Net observations report
  12. GRB 220930A: BOOTES-5/JGT early optical upper limit
  13. GRB 220930A: Prompt enhanced Swift-XRT position
  14. GRB 220930A: COATLI Upper Limits
  15. GRB 220930A: Swift detection of a burst


Download all Circulars as a .tar.gz archive:
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