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"

36020 results found.

  1. GRB 991216: J band spectrophotometry
  2. GRB 991216: Detection of the Host and/or Absorber Galaxy
  3. IPN localization of GRB991226
  4. Single IPN error box for GRB991221
  5. IPN error boxes for GRB991221
  6. GRB 991216 RXTE ASM Observations
  7. IPN error box for GRB991216
  8. GRB 991216: Updated BATSE parameters
  9. Lowell/Perkins observation of GRB 991216
  10. GRB 991217 (SAX J2303.2+0015) Optical observations
  11. Chandra observation of the X-ray afterglow of GRB991216
  12. GRB 991216, optical observations
  13. GRB 991216 Optical Observations
  14. GRB 991216 Optical spectroscopy/imaging
  15. K observations of GRB991216
  16. GRB 991217 (SAX J2303.2+0015) Optical observations
  17. GRB991216 Spectroscopy
  18. Lowell/Perkins observation of GRB 991216
  19. GRB991216, optical observations
  20. Refined IPN localization of GRB991216
  21. GRB 991216 Radio Observations
  22. GRB 991217
  23. GRB 991208 Keck Spectroscopy
  24. GRB 991208 Infrared Detection
  25. GRB 991216--Summary of RXTE Observations
  26. GRB 991216 Optical Observations
  27. GRB 991216, optical observations
  28. GRB 991208 SAO-RAS Spectroscopy
  29. SAX J2303.2+0015: an x-ray/GRB?
  30. GRB 991216, Optical Transient
  31. GRB 991216, Optical Afterglow
  32. GRB 991216: Comparison with DPOSS images
  33. GRB 991208 optical observations
  34. Lowell/Perkins observation of GRB 991216
  35. GRB 991216 Optical Observation
  36. GRB 991208 Keck Spectroscopy
  37. GRB 991216: Extremely bright BATSE burst
  38. GRB991208, optical observations
  39. GRB 991208 Keck Spectroscopy
  40. GRB991208 - millimeter detection
  41. GRB 991208, Optical Observation
  42. GRB 991208 - OVRO detection
  43. GRB 991208 Optical Decay
  44. GRB 991208 optical observations
  45. GRB 991208 optical observations
  46. GRB 991208: Radio Observations
  47. IPN localization of GRB991208
  48. Optical Observations of GRB991105
  49. GRB991106: BeppoSAX/BATSE results
  50. GRB 991106, optical observations
  51. GRB991106, near-infrared observations
  52. BeppoSAX NFI Observation of GRB991106
  53. GRB 991106, radio observations
  54. GRB991106: the first BeppoSAX short GRB detection?
  55. GRB 991105: BATSE Observations
  56. IPN localization of GRB991105
  57. GRB 991106 Optical Observations
  58. GRB 991105, optical observations
  59. GRB991106, optical observation at SAO-RAS
  60. GRB 991106, LOTIS Optical Observations
  61. GRB 991106, optical observations
  62. BeppoSAX GRB Alert: GRB991106
  63. BeppoSAX MAIL n. 99/30: GRB991105 refined position (fwd)
  64. GRB ALERT: GRB991105
  65. GRB 991014 - X-ray afterglow identification by BeppoSAX-NFI
  66. GRB 991014, Optical Observations
  67. GRB 991014 - BeppoSAX NFI observations
  68. GRB 991014, Optical Observations
  69. GRB 991014, radio observations
  70. GRB991014 BATSE Observations
  71. GRB 991014, Optical Observations
  72. GRB 991014, optical observations
  73. Super-LOTIS optical observation of GRB991014
  74. IPN/NFI error box for GRB991014
  75. IPN localization of GRB991014 - CORRECTION
  76. IPN localization of GRB991014
  77. BeppoSAX ALERT: GRB991014
  78. GRB 990915 optical observations
  79. GRB 990907 optical observations
  80. BATSE GRB trigger criteria
  81. Optical Observations of GRB990907
  82. IPN error box for GRB990915 (=BATSE 7766)
  83. IPN localization of BATSE #7766 (GRB990915)
  84. IPN localization of GRB990907
  85. GRB990908, another BeppoSAX-GRBM/WFC burst detection
  86. BeppoSAX MAIL n. 99/24: GRB ALERT: GRB990907
  87. GRB 990712 Late Optical Decay and Host Galaxy
  88. GRB 990712, Optical Observation
  89. GRB990806: BATSE Observations
  90. GRB 990806 Optical observations
  91. Optical Observations of GRB990806
  92. GRB 990806, Optical Observations
  93. GRB 990806, optical observations
  94. GRB 990806, Optical Observations
  95. GRB990806 UBVRIJHK observations
  96. BeppoSAX ALERT GRB990806: Summer GRB
  97. GRB 990712 Optical Observations
  98. GRB990705: No Evidence for Neutrino Signal
  99. GRB 990712 Optical Decay: Indication of Bright Host Galaxy
  100. VLT spectrum of GRB990712

Advanced

Download all Circulars as a .tar.gz archive (updated once a day):
Looking for U.S. government information and services? Visit USA.gov