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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"

24937 results found.

  1. IPN web site of GRBs
  2. GRB980425 BATSE observations
  3. SAX J0840.7+2248 Optical Observations
  4. GRB980425: optical obs.
  5. GRB980425: Radio Observations
  6. report on BSAX observations of GRB980425
  7. GRB 980329 ROSAT observation
  8. GRB980326 X-ray Observations
  9. GRB980326, optical observations
  10. GRB980326, optical observations
  11. GRB980329, Fading IR counterpart to radio source
  12. GRB980329 Keck K-band observations
  13. GRB980329 sub-millimeter observations
  14. GRB980329 optical observations
  15. GRB980329 near-IR observations
  16. GRB980329 near-IR observations
  17. GRB980326 optical observations
  18. GRB980329 optical observations
  19. GRB980329 VLA observations
  20. GRB980329 optical observations
  21. GRB980329 optical observations
  22. GRB980326 optical observations
  23. GRB980326 optical observations
  24. Optical Observations of GRB 970508
  25. Near-IR follow-up on GRB 971227
  26. Optical Observations of the GRB 971227 field
  27. Optical Observations on GRB 971227
  28. GRB971227: Plaskett R-band observations
  29. GRB 971227: Optical clarifications
  30. GRB971227: Further CAHA R-band images
  31. GRB971227: LOTIS observations
  32. GRB971214: Optical Observations and Calibrations
  33. GRB 971214: Optical Observations
  34. Radio Observations of GRB 971214 at the VLA
  35. GRB 971024: Refined analysis by USNOFS Observations
  36. GRB 971024: KPNO Optical Observations
  37. GRB 970828: Palomar Observations

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