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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. GRB980519 optical observations
  2. GRB980515, BeppoSAX IAUC to be submitted
  3. BATSE on-board GRB trigger change
  4. GRB980519, BeppoSAX-WFC updated position
  5. GRB980519, BeppoSAX-WFC position
  6. GRB980515: SAX-WFC updated position
  7. BeppoSAX GRB ALERT: updated position of grb980515
  8. GRB 980425 Radio Light Curve
  9. GRB 980425 Brightness Temperature
  10. BSAX Observations of GRB980425 field
  11. IPN web site of GRBs
  12. GRB980425 BATSE observations
  13. SAX J0840.7+2248 Optical Observations
  14. GRB 980425 optical observations
  15. GRB980425: optical obs.
  16. GRB980425: Radio Observations
  17. GRB 980425 optical observations
  18. report on BSAX observations of GRB980425
  19. GRB 980425 optical observations
  20. GRB 980329 ROSAT observation
  21. GRB980326 X-ray Observations
  22. GRB980326, optical observations
  23. GRB980326, optical observations
  24. GRB980329, Fading IR counterpart to radio source
  25. GRByymmdd, Announcement of automation
  26. GRB980326 IPN annulus
  27. GRB980329
  28. GRB980329 Keck K-band observations
  29. GRB980329 sub-millimeter observations
  30. GRB980329 IPN annulus
  31. GRB980329 optical observations
  32. GRB980329 near-IR observations
  33. GRB980329 near-IR observations
  34. GRB980329 optical observations
  35. GRB980329 infrared observations
  36. GRB980329 optical observations
  37. GRB980326 optical observations
  38. GRB980329 optical observations
  39. GRB980329 VLA observations
  40. GRB980329 near IR observations
  41. GRB980329 optical observations
  42. GRB980329 optical observations
  43. GRB980329 optical observations
  44. GRB980326 optical observations
  45. GRB980326 optical observations
  46. GRB980326 optical observations
  47. GRB980326 optical observations
  48. GRB970508 SAO RAS optical observations
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Advanced

Download all Circulars as a .tar.gz archive (updated once a day):
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