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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').

25 results found.

  1. GRB 230818A: further radio observations with the VLA
  2. Konus-Wind detection of GRB 231215A
  3. GRB 230818A: radio observation with the VLA
  4. GRID detection of GRB 230818A
  5. GRB 230818A: Swift-BAT refined analysis
  6. Konus-Wind detection of GRB 230818A
  7. GRB 230818A: Fermi GBM Observation
  8. GRB 230818A: Nickel and KAIT telescope optical observations
  9. GRB 230818A: SAO RAS 6-m telescope spectroscopy
  10. GRB 230818A: further SAO RAS Zeiss-1000 observations
  11. GRB 230818A: AKO Upper Limit
  12. GRB 230818A: AstroSat CZTI detection
  13. GRB 230818A: Tautenburg observations
  14. GRB 230818A: Leavitt Observatory upper limit
  15. GRB 230818A: Swift-XRT refined Analysis
  16. GRB 230818A: Bassano Bresciano Observatory optical observations
  17. GRB 230818A: KGO RC-25 optical observations
  18. GRB 230818A: Swift/UVOT Detection
  19. GRB 230818A: NOT photometry and spectroscopy
  20. GRB 230818A: Enhanced Swift-XRT position
  21. GRB 230818A: SAO RAS Zeiss-1000 observations
  22. Fermi GRB 230818A: Global MASTER-Net observations report
  23. GRB 230818A: GOTO optical afterglow detection
  24. GRB 230818A: Swift detection of a burst
  25. GRB 230818A: Fermi GBM Final Real-time Localization


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