Skip to main content
JSON Notices via Email, Kafka Cron Jobs, Submitter Profile, GCN is Hiring. See news and announcements

GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. 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. GRB 100331A: BOOTES-3 observations
  2. Konus-Wind observation of GRB 100324B
  3. GRB 100331A: A long GRB detected by INTEGRAL
  4. IPN triangulation of GRB100324B
  5. Konus-Wind observation of GRB 100322A
  6. Short X-ray Transient detected by MAXI/GSC
  7. Fermi GBM detection of four Solar Flares
  8. GRB 100322A: Suzaku WAM observation of the prompt emission
  9. Fermi/GBM and Swift/BAT detection of a burst from SGR 1806-20
  10. GRB 100325A: Fermi LAT detection
  11. GROND observations of GRB100316D/SN2010bh
  12. GRB 100325A: Fermi GBM detection
  13. GRB 100324A: GROND observations
  14. GRB 100324A found in ground analysis of BAT data
  15. Emerging Supernova in the Afterglow of GRB 100316D
  16. GRB 100322B or possible Galactic transient detected in ground analysis of BAT data
  17. GRB 100316D: Spectroscopic Discovery of a Supernova from Magellan
  18. SGR 1833-0832: Swift/UVOT Upper Limits
  19. GRB 100322A: Fermi GBM detection
  20. SGR 1833-0832: Archival Chandra Observations
  21. SGR 1833-0832 is pulsed at 7.56 seconds
  22. SGR 1833-0832 is pulsed at 7.56 seconds
  23. Possible pulsation period in SGR 1833-0832
  24. Discovery of the Spin Period of SGR 1833-0832
  25. GRB 100316D: ATCA radio observations
  26. GRB 100319A: correction to GCN 10527
  27. Probable SGR 1833-0832: Swift-XRT refined analysis
  28. Probable SGR 1833-0832: Enhanced Swift-XRT position
  29. Swift-XRT refined position of the probable new SGR 1833-0832
  30. Swift-BAT refined analysis of the probable new SGR 1833-0832
  31. GRB 100219A: MASTER-Net optical alert observations
  32. GRB 100319A: Swift detection of a burst; possible SGR
  33. GRB 100316D: Possible Supernova
  34. GRB 100316D: Pre-burst emission measured by BAT
  35. GRB 100316D: Further Gemini observations
  36. GRB 100219A: optical upper limit
  37. GRB 100316A: optical observations in CrAO
  38. GRB 100316D: Swift/UVOT Observations
  39. GRB 100316D: Swift XRT enhanced position and further refined analysis
  40. GRB 100316B: Swift-XRT refined analysis
  41. Tentative redshift of GRB100316D from X-ray data
  42. GRB 100316C: GROND Detection of a Optical/NIR Afterglow Candidate
  43. Trigger 416226 is probably not a GRB
  44. GRB 100316D: GROND Detection of the Optical/NIR Afterglow Candidate
  45. GRB 100316D: Gemini/GMOS and VLT/X-shooter observations
  46. GRB 100316D: VLT/X-shooter observations
  47. GRB 100316D: Swift-BAT refined analysis
  48. GRB100316C: Swift/UVOT Upper Limits
  49. GRB 100316C: Swift-BAT refined analysis
  50. GRB 100316B: Swift/UVOT observations
  51. GRB 100316C: Swift-XRT team refined analysis
  52. GRB 100316C: Enhanced Swift-XRT position
  53. GRB 100316D: Swift XRT refined analysis
  54. GRB 100316A: TAROT Calern observatory optical observations
  55. GRB 100316A: Swift-XRT refined analysis
  56. GRB 100316B: Enhanced Swift-XRT position
  57. GRB 100316A: Swift-BAT refined analysis
  58. GRB 100316B: Swift-BAT refined analysis
  59. GRB100316A: Swift/UVOT Upper Limits
  60. Trigger 416140 is almost certainly not a GRB
  61. GRB 100316C: BOOTES-3 observations
  62. GRB 100316D: Swift detection of a burst
  63. GRB 100316B: VLT/X-shooter redshift
  64. GRB 100316B: Skynet/PROMPT Observations of Fading
  65. GRB 100316B: GROND Detection of the Optical/NIR Afterglow Candidate
  66. XRF 100315A: MAXI/GSC detection of a short X-ray transient
  67. GRB 100316C: Swift detection of a burst
  68. GRB 100316A: Enhanced Swift-XRT position
  69. GRB 100316B: Swift detection of a burst with optical counterpart
  70. GRB 100316 optical candidate from 1.23m CAHA telescope
  71. GRB 100316 optical candidate from 1.23m CAHA telescope
  72. GRB 100316A: Swift/UVOT Observations
  73. GRB 100316A: Swift-XRT detection
  74. GRB 100316A: Swift detection of a burst
  75. IBAS Alert 5992 is not a GRB, but XTE J1855-026
  76. GRB100305A: Optical upper limits at IAO
  77. GRB 100305A: Super-LOTIS early observations
  78. GRB100302A : LOAO observations and Lulin afterglow analysis
  79. GRB 100305A, Swift-BAT refined analysis
  80. GRB 100305A: Gemini z'-band observation
  81. GRB 100305A: Swift/UVOT Upper Limits
  82. GRB 100305A: Swift-XRT refined analysis
  83. GRB 100305A Optical Observations
  84. GRB 100305A: Enhanced Swift-XRT position
  85. GRB 100305A: Gemini-N OT candidate
  86. GRB 100305A: PAIRITEL NIR Upper Limits
  87. GRB 100305A: P60 Observations
  88. GRB 100305A: Swift detection of a burst
  89. GRB 100302A: Ondrejov 65cm limit
  90. GRB 100302A: Swift/UVOT Upper Limits
  91. GRB 100302A: Swift-XRT refined analysis
  92. GRB 100302A: Gemini-North redshift
  93. GRB 100302A: Gemini-N OT confirmation
  94. GRB 100302A: Optical observations at Crni Vrh
  95. GRB 100302A: MASTER-Net optical alert observations
  96. GRB 100302A, Swift-BAT refined analysis
  97. GRB 1000302A : A possible afterglow candidate
  98. GRB 100302A: Enhanced Swift-XRT position
  99. GRB 100302A: Skynet/DAO Observations
  100. GRB 100302A: Swift detection of a burst

Advanced

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