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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"

4927 results found.

  1. GRB 000201: TAROT optical observations
  2. IPN annulus for GRB000115
  3. Second RXTE Observation of GRB 000115
  4. GRB991216, UBVRIJHK field photometry
  5. GCN resumes full operations
  6. IPN error box for GRB991216
  7. GRB991216, optical observations
  8. IPN localization of GRB991105
  9. GRB 990806, Optical Observations
  10. GRB990704 radio and optical observations
  11. GRB 990704, optical observations
  12. Identification of a possible optical counterpart for GRB990704
  13. IPN error box for GRB990527
  14. GRB 990506 optical observations
  15. IPN localization for GRB990506
  16. GRB990321 REFINED IPN ANNULUS
  17. GRB990321 IPN TRIANGULATION
  18. ASM/IPN error box for GRB 990308 (BATSE #7457)
  19. GRB990123, Upcoming HST Service Observations
  20. GRB990123, optical observation
  21. GRB 981220 Optical observations
  22. GRB 981220:Optical Observations
  23. GRB981226 Optical Observation
  24. BeppoSAX NFI Observation of GRB980425
  25. GRB980326 X-ray Observations
  26. GRB980329 Keck K-band observations
  27. GRB980329 infrared observations

Advanced

Download all Circulars as a .tar.gz archive:
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