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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').

28 results found.

  1. GRB 231215A: further radio observations with the VLA
  2. GRB 231215A: radio detection with the VLA
  3. GRID detection of GRB 231215A
  4. GRB 231215A: AMI-LA radio detection
  5. GRB 231215A: Osservatorio Astronomico Nastro Verde upper limit
  6. GRB 231215A: Swift-BAT refined analysis
  7. GRB 231215A: GRBAlpha detection
  8. Konus-Wind detection of GRB 231215A
  9. GRB 231215A: optical afterglow detection from the INAF Asiago Observatory
  10. GRB 231215A: NOT optical observations
  11. GRB 231215A: Redshift from OSIRIS+ / GTC
  12. GRB 231215A: GAD Observatory, La Spezia, Italy upper limit;
  13. GRB 231215A: Fermi GBM observation
  14. GRB 231215A: CALET Gamma-Ray Burst Monitor detection
  15. GRB 231215A : OHP/T193 optical afterglow detection
  16. GRB 231215A: Swift/UVOT Detection
  17. GRB 231215A: Swift-XRT refined Analysis
  18. GRB 231215A: BOOTES-4/MET optical detection
  19. GRB 231215A: AKO Optical Upper Limit
  20. GRB 231215A: AGILE detection
  21. GRB 231215A: Enhanced Swift-XRT position
  22. GRB 231215A: GROWTH-India optical follow-up
  23. GRB 231215A : Nanshan/HMT optical observations
  24. GRB 231215A: AstroSat CZTI detection
  25. GRB 231215A : MITSuME Akeno optical afterglow candidate detection
  26. GRB 231215A: Mondy optical bright afterglow detection
  27. GRB 231215A: Swift-XRT observations
  28. GRB 231215A: Swift detection of a burst


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