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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"
  1. GRB980329 Keck K-band observations
  2. GRB980329 sub-millimeter observations
  3. GRB980329 IPN annulus
  4. GRB980329 optical observations
  5. GRB980329 near-IR observations
  6. GRB980329 near-IR observations
  7. GRB980329 optical observations
  8. GRB980329 infrared observations
  9. GRB980329 optical observations
  10. GRB980326 optical observations
  11. GRB980329 optical observations
  12. GRB980329 VLA observations
  13. GRB980329 near IR observations
  14. GRB980329 optical observations
  15. GRB980329 optical observations
  16. GRB980329 optical observations
  17. GRB980326 optical observations
  18. GRB980326 optical observations
  19. GRB980326 optical observations
  20. GRB980326 optical observations
  21. GRB970508 SAO RAS optical observations
  22. Optical Observations of GRB 970508
  23. GRB 971214: Redshift from Keck Observations
  24. Near-IR follow-up on GRB 971227
  25. GRB971214: Keck R & I-band Observations
  26. GRB 971227: Optical Observations
  27. Optical Observations of the GRB 971227 field
  28. Optical Observations on GRB 971227
  29. GRB971227: Plaskett R-band observations
  30. GRB 971227: Optical clarifications
  31. Optical Observations for GRB 971227
  32. GRB971227: Further CAHA R-band images
  33. GRB971227: LOTIS observations
  34. GRB 971227: CAHA R-band images
  35. GRB 971227: Optical observations
  36. GRB971214: Optical Observations and Calibrations
  37. Sub-millimeter Observations of GRB 971214 at the JCMT
  38. GRB 971214: EUVE Observations
  39. GRB 971214: Redshift from Keck Optical Observations
  40. GRB 971214: Redshift from Keck Optical Observations
  41. GRB 971214: Apache Point Observatory Optical Observations
  42. GRB 971214: KPNO Optical Observations
  43. Optical Observations of GRB 971214 at Keck
  44. GRB 971214: Optical Observations
  45. Radio Observations of GRB 971214 at the VLA
  46. GRB 971214: USNOFS Observations Summary
  47. GRB 971024: KPNO Optical Observations Summary
  48. GRB 971024: Refined analysis by USNOFS Observations
  49. GRB 971024: KPNO Optical Observations
  50. GRB 971024: USNO Observations
  51. GRB 970925: BATSE Localization
  52. IRAS 18119-1342 and the possible new SGR
  53. Possible new SGR from US Naval Observatory
  54. RXTE Observations of SGR 1814-13
  55. GRB 970828: Palomar Observations
  56. GRB 970228: Keck/LRIS Optical Observations

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