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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').

21 results found.

  1. Konus-Wind detection of GRB 231118A
  2. GRB 231118A: REM optical afterglow detection
  3. GRB 231118A: ATCA detection of radio counterpart
  4. GRB 231118A: GRBAlpha detection
  5. GRB 231118A: VZLUSAT-2 detection
  6. GRB 231118A: Swift-BAT refined analysis
  7. 231118A: Swift-UVOT Detection
  8. GRB 231118A: Fermi GBM observation
  9. GRB 231118A: Swift-XRT refined Analysis
  10. GRB 231118A: MeerLICHT afterglow detection
  11. GRB 231118A: VLT/X-shooter redshift
  12. GRB 231118A: AstroSat CZTI detection
  13. GRB 231118A: Las Cumbres optical detection
  14. GRB 231118A: LCOGT Optical Observations
  15. GRB 231118A: MASTER OT observation
  16. GRB 231118A: Continued Skynet Observations
  17. GRB 231118A: Enhanced Swift-XRT position
  18. GRB 231118A: Swift-XRT position
  19. GRB 231118A: Skynet Optical Afterglow Discovery
  20. GRB 231118A: Swift detection of a burst
  21. GRB 231118A: Fermi GBM Final Real-time Localization


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