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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"

21643 results found.

  1. GRB 980519 Optical Observations
  2. GRB980519 Optical Observations
  3. GRB 980519 Optical Observations
  4. GRB980515, BeppoSAX IAUC to be submitted
  5. BATSE on-board GRB trigger change
  6. GRB980519, BeppoSAX-WFC updated position
  7. GRB980515: SAX-WFC updated position
  8. GRB 980425 Radio Light Curve
  9. BSAX Observations of GRB980425 field
  10. IPN web site of GRBs
  11. SAX J0840.7+2248 Optical Observations
  12. GRB980425: optical obs.
  13. GRB980425: Radio Observations
  14. report on BSAX observations of GRB980425
  15. GRB 980329 ROSAT observation
  16. GRB980326 X-ray Observations
  17. GRB980326, optical observations
  18. GRB980326, optical observations
  19. GRB980329
  20. GRB980329 Keck K-band observations
  21. GRB980326 optical observations
  22. GRB980329 optical observations
  23. GRB980329 VLA observations
  24. GRB980329 optical observations
  25. GRB980326 optical observations
  26. GRB980326 optical observations
  27. GRB980326 optical observations
  28. Optical Observations of GRB 970508
  29. Near-IR follow-up on GRB 971227
  30. Optical Observations of the GRB 971227 field
  31. Optical Observations on GRB 971227
  32. GRB971227: Plaskett R-band observations
  33. GRB 971227: Optical clarifications
  34. GRB971227: Further CAHA R-band images
  35. GRB971227: LOTIS observations
  36. GRB971214: Optical Observations and Calibrations
  37. Sub-millimeter Observations of GRB 971214 at the JCMT
  38. GRB 971214: EUVE Observations
  39. GRB 971214: KPNO Optical Observations
  40. GRB 971214: Optical Observations
  41. Radio Observations of GRB 971214 at the VLA
  42. GRB 971024: KPNO Optical Observations
  43. GRB 970828: Palomar Observations

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Download all Circulars as a .tar.gz archive:
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