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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').
Advanced Search

To narrow the search results, use advanced search syntax. This allows for specifying which circular field to search (submitter, subject, and/or body). For additional information, refer to the advanced search documentation.

Advanced Search Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

40 results found.

  1. GRB 160327A: KAIT optical afterglow confirmation
  2. GRB 151027A: Maidanak optical observations
  3. 610 MHz detection of GRB 151027A with the GMRT
  4. GRB 151027A: SAO RAS and Mt. Terskol observations
  5. GRB151027A; Optical observations
  6. GMRT radio detection of GRB 151027A
  7. GRB 151027A: continued Mondy optical observations
  8. GRB 151027A: Hankasalmi optical observations
  9. GRB 151027A: Mondy optical observations
  10. GRB 151027A: Mt. Terskol observatory optical observation
  11. GRB 151027A: the missing GeV component
  12. GRB 151027A: Correction to GCN 18519
  13. GRB 151027A: optical follow-up observations
  14. GRB 151027A: Continued P60 Monitoring
  15. GRB 151027A: Optical counterpart detection
  16. GRB 151027A: MAXI/GSC detection
  17. GRB 151027A: SAO RAS optical observations
  18. GRB 151027A: NOT optical and NIR observations
  19. GRB 151027A: T100 observations
  20. Konus-Wind observation of GRB 151027A
  21. GRB 151027A : Xinglong TNT optical observation
  22. GRB 151027A: continued GMG observation
  23. GRB 151027A: LCOGT-McDonald afterglow observations
  24. GRB 151027A: VLA detection
  25. GRB 151027A: THO optical observations
  26. GRB 151027A: UVOT Observations
  27. GRB 151027A: Swift-BAT refined analysis
  28. GRB 151027A: Early RAPTOR Observations
  29. GRB 151027A: GMG observation
  30. GRB 151027A: Fermi GBM observation
  31. GRB 151027A: MITSuME Akeno Optical observation
  32. GRB 151027A: Swift-XRT refined Analysis
  33. GRB 151027A: Keck/HIRES redshift
  34. GRB 151027A: Weihai optical observations
  35. Tentative redshift for GRB 151027A from Swift-XRT data
  36. GRB 151027A: Enhanced Swift-XRT position
  37. GRB 151027A: P60 afterglow confirmation and rebrightening
  38. GRB 151027A : ISON-NM early optical detection
  39. GRB 151027A: KAIT optical afterglow confirmation
  40. GRB 151027A: Swift detection of a burst with a bright optical afterglow

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