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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"

25842 results found.

  1. GRB980519 Optical Observations
  2. GRB980519 Optical Observations
  3. GRB 980519 Optical Observations
  4. GRB980515, BeppoSAX IAUC to be submitted
  5. BSAX Observations of GRB980425 field
  6. IPN web site of GRBs
  7. GRB980425 BATSE observations
  8. SAX J0840.7+2248 Optical Observations
  9. GRB980425: optical obs.
  10. GRB980425: Radio Observations
  11. report on BSAX observations of GRB980425
  12. GRB 980329 ROSAT observation
  13. GRB980326 X-ray Observations
  14. GRB980326, optical observations
  15. GRB980326, optical observations
  16. GRB980329, Fading IR counterpart to radio source
  17. GRB980329 Keck K-band observations
  18. GRB980329 sub-millimeter observations
  19. GRB980329 optical observations
  20. GRB980329 near-IR observations
  21. GRB980329 near-IR observations
  22. GRB980326 optical observations
  23. GRB980329 optical observations
  24. GRB980329 VLA observations
  25. GRB980329 optical observations
  26. GRB980329 optical observations
  27. GRB980326 optical observations
  28. GRB980326 optical observations
  29. Optical Observations of GRB 970508
  30. Near-IR follow-up on GRB 971227
  31. Optical Observations of the GRB 971227 field
  32. Optical Observations on GRB 971227
  33. GRB971227: Plaskett R-band observations
  34. GRB 971227: Optical clarifications
  35. GRB971227: Further CAHA R-band images
  36. GRB971227: LOTIS observations
  37. GRB971214: Optical Observations and Calibrations
  38. GRB 971214: Optical Observations
  39. Radio Observations of GRB 971214 at the VLA
  40. GRB 971024: Refined analysis by USNOFS Observations
  41. GRB 971024: KPNO Optical Observations
  42. GRB 970828: Palomar Observations

Advanced

Download all Circulars as a .tar.gz archive:
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