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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"

33846 results found.

  1. GRB980326 IPN annulus
  2. GRB980329 sub-millimeter observations
  3. GRB980329 IPN annulus
  4. GRB980329 near-IR observations
  5. GRB980326 optical observations
  6. GRB980329 optical observations
  7. GRB980329 VLA observations
  8. GRB980329 near IR observations
  9. GRB980329 optical observations
  10. GRB980329 optical observations
  11. GRB980326 optical observations
  12. GRB980326 optical observations
  13. GRB970508 SAO RAS optical observations
  14. Optical Observations of GRB 970508
  15. GRB 971214: Redshift from Keck Observations
  16. Near-IR follow-up on GRB 971227
  17. GRB971214: Keck R & I-band Observations
  18. GRB 971227: Optical Observations
  19. Optical Observations of the GRB 971227 field
  20. Optical Observations on GRB 971227
  21. GRB971227: Plaskett R-band observations
  22. GRB 971227: Optical clarifications
  23. Optical Observations for GRB 971227
  24. GRB971227: Further CAHA R-band images
  25. GRB971227: LOTIS observations
  26. GRB 971227: CAHA R-band images
  27. GRB 971227: Optical observations
  28. Sub-millimeter Observations of GRB 971214 at the JCMT
  29. GRB 971214: EUVE Observations
  30. GRB 971214: Redshift from Keck Optical Observations
  31. GRB 971214: Redshift from Keck Optical Observations
  32. GRB 971214: Apache Point Observatory Optical Observations
  33. GRB 971214: KPNO Optical Observations
  34. Optical Observations of GRB 971214 at Keck
  35. GRB 971214: Optical Observations
  36. Radio Observations of GRB 971214 at the VLA
  37. GRB 971214: USNOFS Observations Summary
  38. GRB 971024: KPNO Optical Observations Summary
  39. GRB 971024: Refined analysis by USNOFS Observations
  40. GRB 971024: KPNO Optical Observations
  41. GRB 971024: USNO Observations
  42. GRB 970925: BATSE Localization
  43. IRAS 18119-1342 and the possible new SGR
  44. Possible new SGR from US Naval Observatory
  45. GRB 970828: Palomar Observations
  46. GRB 970228: Keck/LRIS Optical Observations

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