Skip to main content
Updates to LVK & CHIME Notices, Schema v7.2.3! See news and announcements

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"

43594 results found.

  1. IPN localization of BATSE #7766 (GRB990915)
  2. GRB990907: BeppoSAX follow up and X-ray afterglow
  3. GRB990907 and 990908
  4. IPN localization of GRB990907
  5. GRB990908, another BeppoSAX-GRBM/WFC burst detection
  6. GRB990907: refined WFC position
  7. BeppoSAX MAIL n. 99/24: GRB ALERT: GRB990907
  8. GRB 990712 Late Optical Decay and Host Galaxy
  9. GRB 990712, Optical Observation
  10. GRB990806 BeppoSAX follow up
  11. GRB990806: BATSE Observations
  12. GRB 990806 Optical observations
  13. Optical Observations of GRB990806
  14. GRB 990806, Optical Observations
  15. GRB 990806, optical observations
  16. GRB 990806, Optical Observations
  17. GRB990806 UBVRIJHK observations
  18. GRB990806: possible X-ray afterglow, BeppoSAX
  19. BeppoSAX ALERT GRB990806: Summer GRB
  20. GRB 990712 Optical Observations
  21. GRB990705: No Evidence for Neutrino Signal
  22. GRB 990712 Optical Decay: Indication of Bright Host Galaxy
  23. VLT spectrum of GRB990712
  24. GRB 990712
  25. Late-time HST/STIS Observations of GRB 990510
  26. Refined BeppoSAX-WFC position of GRB990712
  27. BeppoSAX NFI Observation of GRB990705
  28. BeppoSAX NFI Observation of GRB990705
  29. GRB 990705, R-band observations
  30. Updated IPN localization of GRB990705
  31. IPN localization of GRB990704
  32. IPN localization of GRB990705
  33. Infrared and Optical Observations of GRB990705
  34. GRB 990705, radio observations
  35. GRB990704: SAX-NFI results summary
  36. BeppoSAX GRB990705: possible X-ray afterglow
  37. GRB 990704 X-ray Observations
  38. GRB 990704 Optical Observations
  39. GRB 990704, optical observations
  40. GRB990704
  41. GRB990705: Intriguing Positional Coincidences
  42. GRB990704
  43. Refined BeppoSAX-WFC position of GRB990704: Errata Corrige
  44. GRB990704, optical observations
  45. GRB990704: possible X-ray afterglow
  46. Identification of a possible optical counterpart for GRB990704
  47. GRB990704
  48. Refined BeppoSAX-WFC position of GRB990704
  49. GRB990704: BeppoSAX detection
  50. BeppoSAX NFI Observation of GRB990627 X-ray afterglow
  51. Optical Observations of GRB990627
  52. GRB 990627, radio observations
  53. GRB990627: BeppoSAX-WFC final location
  54. BeppoSAX: GRB990625
  55. Late-time HST/STIS Observation of GRB 990123
  56. GRB 990506 - clarification to GCN 352
  57. GRB 990506 - Optical Observations
  58. Optical Observations of GRB 990506
  59. GRB 990506 Radio Transient
  60. GRB990527 Optical Observations
  61. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  62. IPN error box for GRB990527
  63. Late Afterglows of GRBs 990510, 990123
  64. X-ray/GRB 1SAX J0835.9+5118, TNG V and R observations
  65. X-ray/GRB 1SAX J0835.9+5118, BATSE Observation
  66. X-ray/GRB 1SAX J0835.9+5118, Optical Observations
  67. GRB 990506 optical observation
  68. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  69. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  70. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  71. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  72. radio observations of X-ray/GRB transient field
  73. optical observation of the X-ray/GRB transient SAX J0835.9+5118
  74. Optical report on X-ray/GRB transient
  75. radio detection of X-ray/GRB transient
  76. BeppoSAX: A new fast X-ray transient
  77. GRB 990510: optical observations
  78. GRB990510: photometric and spectroscopic observations with the VLT
  79. GRB 990510: optical linear polarization
  80. GRB 990510: optical observations
  81. GRB990510, VI observations
  82. GRB 990506 R band observations
  83. GRB990510: X-ray afterglow
  84. GRB 990510: optical observation
  85. VLT spectrum of GRB990510
  86. GRB 990510: Broad Band Break
  87. GRB 990510: BATSE Observations
  88. GRB 990510 Optical Observations
  89. GRB 990510, BVI photometry
  90. GRB 990510 optical observations
  91. GRB 990510: BeppoSAX/GRBM observations
  92. GRB990510 optical observations
  93. GRB990510
  94. GRB 990510 optical observations
  95. GRB 990510 optical observations
  96. GRB990510: NFI X-ray source
  97. GRB 990510 optical observations
  98. IPN localization of GRB990510
  99. GRB 990506 Radio Observations
  100. GRB 990123, optical monitoring

Advanced

Download all Circulars as a .tar.gz archive (updated once a day):
Questions or comments?
Contact GCN directly.
Have you found a bug in GCN?
Open an issue.
Want to contribute code to GCN?
Get involved on GitHub.

gcn.nasa.gov

A service of the Astrophysics Science Division at NASA Goddard Space Flight Center

Looking for U.S. government information and services? Visit USA.gov