Skip to main content
New! Super-Kamiokande JSON Notices and Schema v4.5.0. 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"

2900 results found.

  1. IPN triangulation of bright GRB 101123A
  2. GGRB 101023A: GROND detection of the optical-NIR afterglow
  3. GRB 101017A: Swift detection of a burst with optical counterpart
  4. Konus-Wind observation of GRB 101014A
  5. GRB 101014A: Fermi GBM detection
  6. MAXI J1659-152: Swift-BAT refined analysis (triggers 434928 and 434931)
  7. GRB 100915A: TAROT Calern observatory optical observations
  8. GRB 100901A: TLS observations, SDSS calibration, decay slope
  9. Konus-Wind observation of GRB 100829A
  10. GRB 100901A: optical observation at Mt.Terskol
  11. GRB 100901A: optical observation at Mt.Terskol
  12. GRB 100901A: MASTER Optical Early Limits
  13. GRB 100823A: optical observations
  14. GRB 100807A: P200 Infrared Observations
  15. GRB 100807A: P60 Optical Afterglow Discovery
  16. GRB 100805A: Swift detection of a burst with an optical counterpart
  17. GRB 100802A: NOT optical observation
  18. GRB 100802A: ROTSE-III Optical Limits
  19. GRB 100802A: Possible Swift/UVOT Detection of Optical Afterglow
  20. GRB 100727A: Swift/UVOT Upper Limits
  21. GRB 100718A: MASTER-Net optical prompt and alert observations
  22. GRB 100702A: Swift detection of a short burst
  23. Swift-BAT trigger 426048 is not a burst
  24. GRB 100513A: CrAO optical observations
  25. GRB 100526A: NOT optical upper limit
  26. GRB 100510A: MAXI/GSC detection
  27. GRB 100418A: Terskol optical observations
  28. GRB 100425A: Swift detection of a burst
  29. Swift Trigger 420256: ROTSE-III Optical Limits
  30. GRB 100420A: Swift detection of a burst
  31. GRB 100316C: BOOTES-3 observations
  32. GRB 100316D: Swift detection of a burst
  33. GRB 100316A: Enhanced Swift-XRT position
  34. GRB 100316B: Swift detection of a burst with optical counterpart
  35. GRB 100316A: Swift-XRT detection
  36. GRB100219A Akeno and Okayama MITSuME Optical Observation
  37. GRB 100203A Detected in Ground Analysis of BAT Data
  38. GRB 100122A: Fermi GBM detection
  39. Konus-Wind observation of GRB 091208A
  40. GRB 091208B, RIMOTS optical upper limits
  41. Short X-ray Transient Detection by MAXI/GSC
  42. GRB 091130: MASTER observations
  43. GRB 091120: MAXI GSC detection
  44. GRB 091117A: Swift/UVOT followup observations
  45. GRB 091024: optical observations
  46. GRB 091018: GROND observations
  47. GRB 091010 optical upper limits
  48. GRB090829: Fermi GBM Detection
  49. GRB 090817: aphotometry of USNO-B1.0 341-0096763
  50. GRB 090813: P60 Optical Afterglow Confirmation
  51. Swift trigger 358760 is probably a noise event
  52. GRB 090728: Swift detection of a burst
  53. IPN Triangulation of bright GRB 090720B
  54. GRB 090715B: VLA radio detection
  55. GRB 090717: Fermi GBM detection
  56. GRB090709A : WSRT Radio observation
  57. GRB 090704: Fermi GBM observation
  58. GRB 090704: a long GRB found in INTEGRAL off-line analysis
  59. GRB 090706: Fermi GBM detection
  60. GRB 090621B: GRT Optical Observation
  61. GRB 090618 : WSRT radio detection
  62. VLA radio detection of GRB 090618
  63. GRB 090424: WSRT Radio Observations
  64. GRB 090607: Swift detection of a burst
  65. GRB 090529C: Fermi GBM detection
  66. GRB 090529: MITSuME optical observation
  67. GRB 090531B: ROTSE-III Optical Limits
  68. GRB 090531: GROND upper limits
  69. GRB 090531: P60 Observations
  70. GRB 090531: Swift detection of a burst
  71. GRB 090530: GRAS002 optical observations
  72. GRB 090515: KAIT optical upper limits
  73. GRB 090510B: Fermi GBM detection
  74. GRB 090426: optical observations
  75. GRB 090426: R-band limit
  76. GRB 090426: Swift detection of a burst with an optical counterpart
  77. GRB 090424: Liverpool Telescope observations
  78. GRB 090423 limiting magnitudes
  79. GRB 090418B: Detection of a bright burst from Swift-BAT slew data
  80. GRB 090417B: Swift-XRT refined analysis
  81. GRB 090411B: Suzaku WAM observation of the prompt emission
  82. GRB 090411B: Fermi GBM detection
  83. Swift-BAT trigger 348781: almost certainly not a burst
  84. GRB 090403: Fermi GBM detection
  85. GRB090401B, RIMOTS optical upper limits
  86. GRB 090401B: Swift detection of a burst
  87. GRB 090324: Suzaku WAM observation of the prompt emission
  88. GRB 090323: Swift-XRT refined analysis
  89. GRB 090313 - PAIRITEL NIR detections
  90. IPN localization of short GRB 090305C
  91. Konus-Wind observation of bright short GRB 090227B
  92. IPN localization of short bright GRB 090227B
  93. VLA radio upper limit on GRB 090205
  94. Konus-Wind observation of GRB 090201
  95. GRB 090201: Swift-XRT refined analysis
  96. GRB 090201: Swift detection of a burst
  97. GRB 090129: Swift-BAT refined analysis
  98. AXP 1E1547.0-5408: Suzaku WAM detections of the current activity
  99. AXP 1E1547.0-5408: Fermi GBM detection of additional bursts
  100. GRB 090113: LOAO Detection Limits in R, I, z, Y-band

Advanced

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