Skip to main content
Due to the lapse in federal government funding, NASA is not updating this website. See the Operations FAQ for GCN impacts.
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"

25787 results found.

  1. GRB 080605: GROND 2nd epoch observations
  2. GRB 080607: Keck/LRIS spectroscopy and redshift
  3. GRB 080607: Swift detection of a burst with optical afterglow
  4. GRB 080607: ROTSE-III Detection of Optical Counterpart
  5. GRB 080605: Swift-UVOT refined analysis
  6. Possible VLA radio detection on INTEGRAL burst GRB 080603A
  7. GRB 080604: VLA radio upper limit
  8. GRB 080605, Swift-BAT refined analysis
  9. GRB 080603B: VLA radio upper limit
  10. GRB 080605, Swift-BAT refined analysis
  11. GRB 080605: Swift-XRT refined analysis
  12. GRB 080605: MASTER VWF 46 s AT observation
  13. GRB 080605: Enhanced Swift-XRT position
  14. GRB 080605: GROND detection of the optical afterglow candidate
  15. GRB 080605: Liverpool Telescope optical afterglow candidate
  16. GRB 080605: Swift/UVOT Position of the Optical Afterglow
  17. GRB 080605: Swift detection of a burst with an optical afterglow
  18. GRB 080603B: TLS Afterglow Observation
  19. GRB 080603A: TLS Afterglow Observation
  20. GRB 080604: MITSuME Okayama observation
  21. GRB 080604, Swift-BAT refined analysis
  22. GRB 080604: Swift-XRT refined analysis
  23. GRB 080603B : Liverpool Telescope Observations
  24. Konus-Wind observation of GRB 080603B
  25. GRB 080603B: Swift-XRT refined analysis
  26. GRB 080603A: Swift-XRT detection of the afterglow
  27. GRB 080430: optical observations
  28. GRB 080603B: Swift/UVOT detection of the afterglow
  29. GRB 080604: Enhanced Swift-XRT position
  30. GRB 080603B, Swift-BAT refined analysis
  31. GRB080603B: RTT150 optical observations, break in light curves
  32. GRB 080604: Swift detection of a burst with an optical afterglow
  33. GRB 080603B: TAROT Calern observatory confirmation of slow optical decay
  34. GRB 080516: TAROT La Silla observatory optical observations
  35. GRB080603B: NOT redshift
  36. GRB 080603B: BOOTES2/TELMA optical observations
  37. GRB 080603B: TAROT Calern observatory detection of a plateau in the light curve
  38. GRB 080603B: Swift detection of a burst with optical afterglow
  39. GRB 080603B: ROTSE-III Detection of Optical Counterpart
  40. GRB 080603: A long GRB detected by INTEGRAL
  41. Possible GRB080603: Faulkes Telescope North optical afterglow candidate
  42. SGR 1627-41: Chandra/RXTE/Swift Observations Scheduled
  43. GRB 080602, Swift-BAT refined analysis
  44. GRB 080602: Swift-XRT refined analysis
  45. Konus-Wind observation of GRB 080602
  46. GRB 080602: NOT R-band upper limit
  47. GRB 080602: Enhanced Swift-XRT position
  48. GRB 080602: Swift detection of a burst
  49. Swift analysis of BAT Slew Survey event (Trigger=009)
  50. GRB 080523: afterglow confirmation and redshift constraints
  51. Konus-Wind observation of reactivation of SGR 1627-41
  52. GRB 080524: Swift XRT and UVOT analysis
  53. GRB 080503: 2nd Epoch Chandra X-ray Observations
  54. GRB 080524: Swift-BAT detection of a burst in ground analysis
  55. GRB 080523: Swift-XRT refined analysis
  56. GRB 080523, Swift-BAT refined analysis
  57. GRB 080523: VLT optical observations
  58. GRB 080523: Enhanced Swift-XRT position
  59. GRB 080523: Swift detection of a burst
  60. GRB 080515: KPNO 4m NIR afterglow detection
  61. GRB 80516: Swift/UVOT Observations
  62. GRB 080515: Swift-XRT position and analysis
  63. GRB 080520, Swift-BAT refined analysis
  64. GRB 080514B: UVOT Observations
  65. GRB080520: Swift/UVOT observations
  66. GRB 080520, GROND observations
  67. GRB 080520: Enhanced Swift-XRT position
  68. GRB 080520: Swift XRT Refined Analysis
  69. GRB 080520: Swift detection of a burst with optical afterglow
  70. GRB 080514B: Suzaku WAM observation of the prompt emission
  71. GRB 080514B: second epoch Swift XRT data confirms the X-ray afterglow
  72. GRB 080517, Swift-BAT refined analysis
  73. GRB 080517: Swift-XRT refined analysis
  74. GRB 080514B: Further NIR observations
  75. GRB 080517: Enhanced Swift-XRT position
  76. GRB080517: Liverpool Telescope Optical Observations
  77. GRB 080517: Swift detection of a burst
  78. GRB 080516, GROND 2nd epoch observations
  79. GRB 080516, GROND observations
  80. GRB 080516, SMARTS optical/IR observations
  81. GRB 080516: Swift-XRT Team refined analysis
  82. GRB 080516, Swift-BAT refined analysis
  83. GRB 080516: Enhanced Swift-XRT position
  84. GRB 080516: Swift detection of a burst
  85. Errartum: VLA upper limit on GRB 080507
  86. VLA upper limit on GRB 080705
  87. GRB 080514B : redshift estimation
  88. IPN triangulation of bright GRB 080513
  89. GRB 080515, Swift-BAT refined analysis
  90. GRB 080514B: slow fading behaviour ?
  91. GRB 080514B: Swift-XRT analysis
  92. GRB 080514B, GROND observations
  93. GRB 080515: Swift detection of a burst
  94. GRB 080514B: Afterglow candidate
  95. GRB 080514B: Watcher observations
  96. GRB 080514B: possible AGILE detection at E>50 MeV
  97. GRB 080514B: SuperAGILE/IPN GRB Localization
  98. procesure for GRB Circular
  99. Swift detection of a possible galactic transient
  100. GRB080514: REM NIR & Optical Observations

Advanced

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