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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. GRB980519 I-band observations
  2. GRB 980519
  3. GRB980519 optical observations
  4. GRB 980519 Optical Observations
  5. GRB980519 BATSE Observations
  6. GRB970519, optical follow-up at Schmidt Calern
  7. GRB980519 optical observations
  8. GRB980519 Optical Observations
  9. GRB980519 Optical Observations
  10. GRB980519 IPN POSITION
  11. GRB980519 Optical Observations
  12. GRB 980519 Optical Observations
  13. GRB980519 optical observations
  14. GRB980515, BeppoSAX IAUC to be submitted
  15. BATSE on-board GRB trigger change
  16. GRB980519, BeppoSAX-WFC updated position
  17. GRB980519, BeppoSAX-WFC position
  18. GRB980515: SAX-WFC updated position
  19. BeppoSAX GRB ALERT: updated position of grb980515
  20. GRB 980425 Radio Light Curve
  21. GRB 980425 Brightness Temperature
  22. BSAX Observations of GRB980425 field
  23. IPN web site of GRBs
  24. GRB980425 BATSE observations
  25. SAX J0840.7+2248 Optical Observations
  26. GRB 980425 optical observations
  27. GRB980425: optical obs.
  28. GRB980425: Radio Observations
  29. GRB 980425 optical observations
  30. report on BSAX observations of GRB980425
  31. GRB 980425 optical observations
  32. GRB 980329 ROSAT observation
  33. GRB980326 X-ray Observations
  34. GRB980326, optical observations
  35. GRB980326, optical observations
  36. GRB980329, Fading IR counterpart to radio source
  37. GRByymmdd, Announcement of automation
  38. GRB980326 IPN annulus
  39. GRB980329
  40. GRB980329 Keck K-band observations
  41. GRB980329 sub-millimeter observations
  42. GRB980329 IPN annulus
  43. GRB980329 optical observations
  44. GRB980329 near-IR observations
  45. GRB980329 near-IR observations
  46. GRB980329 optical observations
  47. GRB980329 infrared observations
  48. GRB980329 optical observations
  49. GRB980326 optical observations
  50. GRB980329 optical observations
  51. GRB980329 VLA observations
  52. GRB980329 near IR observations
  53. GRB980329 optical observations
  54. GRB980329 optical observations
  55. GRB980329 optical observations
  56. GRB980326 optical observations
  57. GRB980326 optical observations
  58. GRB980326 optical observations
  59. GRB980326 optical observations
  60. GRB970508 SAO RAS optical observations
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Advanced

Download all Circulars as a .tar.gz archive (updated once a day):
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