Skip to main content
End of Swift Science Operations, CHIME Notices Unavailable During Upgrade. 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"

43106 results found.

  1. GRB 120521B/Fermi Trigger 359284074: early MASTER-ICATE optical limit
  2. GRB 120521B: TAROT La Silla observatory optical observations
  3. GRB 120521B: Swift detection of a burst
  4. GRB 120521A: Enhanced Swift-XRT position
  5. GRB 120521A: TAROT La Silla observatory optical observations
  6. GRB 120521A: Swift detection of a short burst
  7. GRB 120514A : Suzaku WAM observation of the prompt emission
  8. GRB 120512A: A long GRB detected by INTEGRAL
  9. Swift Trigger 522245 is a noise fluctuation near IGR J17091-3624
  10. GRB 120514A: GROND upper limits
  11. GRB 120514A: Swift/UVOT Upper Limits
  12. Konus-Wind observation of GRB 120510A
  13. GRB 120514A: Swift-XRT refined Analysis
  14. GRB 120514A: APEX observations of the submm counterpart
  15. GRB 120514A: Enhanced Swift-XRT position
  16. GRB 120514A: Swift-BAT refined analysis
  17. GRB 120514A: TAROT Calern observatory optical observations
  18. GRB 120514A: Swift detection of a burst
  19. GRB 120422A: Konkoly optical observations
  20. Fermi GBM Trigger 358364818 is not a GRB
  21. Fermi Trigger 358364818: BOOTES-4 observations
  22. GRB 120510B/Fermi Trigger 358364818: MASTER possible OT candidate
  23. GRB 120510A: Swift XRT and UVOT observations
  24. GRB 120510A: MASTER follow up observations
  25. GRB 120510A: MAXI/GSC detection of a burst
  26. GRB 120422A: SN identification from GTC
  27. Fermi/GBM detection of a burst from the magnetar 1E 2259+5
  28. GRB 120422A: P200 NIR detection
  29. GRB 120422A: CARMA 3mm observations
  30. GRB 120422A: VLT/X-shooter spectroscopic evidence for a SN
  31. GRB 120422A: i-band re-brightening and possible SN detection
  32. GRB 120427A: MASTER follow up observations
  33. GRB 120422A: optical observations
  34. Konus-Wind observation of GRB 120427A
  35. IPN Triangulation of GRB 120427A
  36. Swift detection of 4U 1630-47
  37. GRB 120422A, the review of the sky area in plate archives
  38. Konus-Wind observation of GRB 120426A
  39. GRB 120422A: Additional Gemini observations and Keck/LRIS spectroscopy
  40. IPN Triangulation of bright GRB 120426A
  41. Swift Trigger 520928 is a noise event
  42. GRB 120422A: MITSuME Ishigakijima upper limit
  43. Swift Trigger 520928 is probably not a burst
  44. GRB 120424A: MAXI/GSC detection of a burst
  45. GRB 120422A: 272 GHz observations from SMA
  46. GRB 120422A: RAPTOR Limits During Gamma-ray Emitting Interval
  47. GRB 120422A: VLT/X-shooter spectroscopy of the GRB counterpart
  48. GRB 120422A GROND observations
  49. GRB 120422A: Super-LOTIS early observations
  50. GRB 120422A: EVLA Detection
  51. GRB 120422A: NOT optical observations
  52. GRB 120422A: Gemini redshift of candidate host
  53. GRB 120422A: Zadko observatory - Gingin optical observations
  54. GRB 120422A: Swift-XRT refined Analysis
  55. GRB 120422A: A Swift/UVOT Detection
  56. GRB 120422A: Enhanced Swift-XRT position
  57. GRB 120422A: Swift-BAT refined analysis
  58. GRB 120422A: Swift detection of a burst
  59. GRB 120419A: Swift-XRT and UVOT observations
  60. GRB 120419A: A long GRB detected by INTEGRAL
  61. SGR1806-20, Swift-BAT refined analysis (Trigger 519868)
  62. Swift Trigger 519874 is probably a noise event
  63. Trigger 519868: Swift detection of SGR1806-20
  64. GRB 120404A: optical observations
  65. GRB 120404A, Optical Observations
  66. GRB 120404A: SMARTS optical/IR observations
  67. GRB 120404A: EVLA Detection
  68. GRB 120404A: MASTER OT observations
  69. GRB120404A: GROND observations show steeply decaying afterglow
  70. GRB120404A: MOA optical observations of the initial rise afterglow
  71. GRB 120404A: VLT/X-shooter redshift confirmation
  72. GRB 120404A: Swift/UVOT Detection
  73. GRB 120404A: MITSuME Ishigakijima Optical Observation
  74. GRB 120404A: MITSuME Okayama Optical Observation
  75. GRB 120403B: Swift-XRT refined Analysis
  76. GRB 120404A: Swift-XRT refined Analysis
  77. GRB 120404A : TNT optical observation
  78. GRB 120404A: Swift-BAT refined analysis
  79. GRB 120401A: GROND Detection of an optical/NIR afterglow candidate
  80. GRB 120404A: Enhanced Swift-XRT position
  81. GRB 120404A: Gemini-N Redshift correction
  82. GRB 120402B: MASTER early OT limit
  83. GRB 120403B: TAROT La Silla observatory optical observations
  84. GRB 120403B: Fermi GBM Observation
  85. GRB 120403B: AAT nIR observations
  86. GRB 120404A: MITSuME Akeno Optical upper limits
  87. GRB 120404A: MASTER early OT limit
  88. GRB 120404A: Swift detection of a burst with an optical counterpart
  89. GRB 120403B: Swift-BAT refined analysis
  90. GRB 120403B: Swift/UVOT Upper Limits
  91. GRB 120403B: Enhanced Swift-XRT position
  92. GRB 120403B: Swift detection of a burst
  93. BAT trigger 519207 was a burst from Cyg X-1, was not GRB 120402A
  94. GRB 120326A, the review of the sky area in plate archives
  95. GRB 120403A: MASTER follow up observations
  96. GRB 120402A: MASTER follow up observations
  97. GRB 120403A, Swift-BAT refined analysis
  98. GRB 120402B: Fermi GBM detection
  99. GRB 120328B: Pi of the Sky simultaneous upper limits
  100. GRB 120326A: Bassano Bresciano Observatory - correction for GCN Cir 13178

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