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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"

2730 results found.

  1. GRB000630, Revised BVRI Field Photometry
  2. GRB000630, Optical Observations
  3. GRB000630: Optical observations
  4. possible optical counterpart of GRB 000630
  5. IPN triangulation of GRB000630
  6. GRB 000408, optical observations
  7. Radio observations of the error box of GRB000301A
  8. GRB000301A [IPN Position]
  9. GRB000226 [IPN Position]
  10. IPN localization of GRB991226
  11. GRB991216 Optical and infrared observations of Beethoven Burst
  12. GRB991216 ('Beethoven Burst') B, R, and K Observations
  13. IPN localization of GRB991208
  14. IPN localization of GRB991105
  15. IPN localization of GRB991014 - CORRECTION
  16. IPN localization of GRB991014
  17. IPN error box for GRB990915 (=BATSE 7766)
  18. GRB 990704, optical observations
  19. GRB 990506, optical observations from +1 to +3 hours
  20. GRB 990123: BVRI standards in the field
  21. GRB990123 Optical Observations
  22. GRB990123, early optical counterpart detection
  23. GRB990123, BeppoSAX WFC detection and NFI planned follow-up
  24. GRB981226, BeppoSAX Christmas GRB
  25. GRB981220 I-band Observations
  26. BATSE on-board GRB trigger change
  27. GRB980326 IPN annulus
  28. GRB980329 IPN annulus
  29. GRB 971024: Refined analysis by USNOFS Observations
  30. GRB 971024: USNO Observations

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Download all Circulars as a .tar.gz archive:
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