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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"
  1. IPN web site of GRBs
  2. GRB980425 BATSE observations
  3. SAX J0840.7+2248 Optical Observations
  4. GRB 980425 optical observations
  5. GRB980425: optical obs.
  6. GRB980425: Radio Observations
  7. GRB 980425 optical observations
  8. report on BSAX observations of GRB980425
  9. GRB 980425 optical observations
  10. GRB 980329 ROSAT observation
  11. GRB980326 X-ray Observations
  12. GRB980326, optical observations
  13. GRB980326, optical observations
  14. GRB980329, Fading IR counterpart to radio source
  15. GRByymmdd, Announcement of automation
  16. GRB980326 IPN annulus
  17. GRB980329
  18. GRB980329 Keck K-band observations
  19. GRB980329 sub-millimeter observations
  20. GRB980329 IPN annulus
  21. GRB980329 optical observations
  22. GRB980329 near-IR observations
  23. GRB980329 near-IR observations
  24. GRB980329 optical observations
  25. GRB980329 infrared observations
  26. GRB980329 optical observations
  27. GRB980326 optical observations
  28. GRB980329 optical observations
  29. GRB980329 VLA observations
  30. GRB980329 near IR observations
  31. GRB980329 optical observations
  32. GRB980329 optical observations
  33. GRB980329 optical observations
  34. GRB980326 optical observations
  35. GRB980326 optical observations
  36. GRB980326 optical observations
  37. GRB980326 optical observations
  38. GRB970508 SAO RAS optical observations
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Advanced

Download all Circulars as a .tar.gz archive:
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