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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"

18033 results found.

  1. GRB 980519 Optical Observations
  2. GRB980519 Optical Observations
  3. GRB 980519 Optical Observations
  4. GRB980515, BeppoSAX IAUC to be submitted
  5. BSAX Observations of GRB980425 field
  6. SAX J0840.7+2248 Optical Observations
  7. GRB980425: optical obs.
  8. GRB980425: Radio Observations
  9. report on BSAX observations of GRB980425
  10. GRB980326 X-ray Observations
  11. GRB980326, optical observations
  12. GRB980326, optical observations
  13. GRB980326 IPN annulus
  14. GRB980329 Keck K-band observations
  15. GRB980326 optical observations
  16. GRB980329 optical observations
  17. GRB980329 VLA observations
  18. GRB980329 optical observations
  19. GRB980326 optical observations
  20. Optical Observations of GRB 970508
  21. Near-IR follow-up on GRB 971227
  22. Optical Observations of the GRB 971227 field
  23. Optical Observations on GRB 971227
  24. GRB971227: Plaskett R-band observations
  25. GRB 971227: Optical clarifications
  26. GRB971227: Further CAHA R-band images
  27. GRB971227: LOTIS observations
  28. GRB 971227: CAHA R-band images
  29. GRB971214: Optical Observations and Calibrations
  30. GRB 971214: Optical Observations
  31. Radio Observations of GRB 971214 at the VLA
  32. GRB 971024: KPNO Optical Observations
  33. GRB 970828: Palomar Observations

Advanced

Download all Circulars as a .tar.gz archive:
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