Skip to main content
Retirement of GCN Classic VOEvent Brokers. 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"
  1. Possible GRB080603: Faulkes Telescope North optical afterglow candidate
  2. SGR 1627-41: Chandra/RXTE/Swift Observations Scheduled
  3. GRB 080602, Swift-BAT refined analysis
  4. GRB 080602: Swift-XRT refined analysis
  5. Konus-Wind observation of GRB 080602
  6. GRB 080602: NOT R-band upper limit
  7. GRB 080602: Enhanced Swift-XRT position
  8. GRB 080602: Swift detection of a burst
  9. Swift analysis of BAT Slew Survey event (Trigger=009)
  10. GRB 080523: afterglow confirmation and redshift constraints
  11. Konus-Wind observation of reactivation of SGR 1627-41
  12. Reactivation of SGR 1627-41
  13. GRB 080524: Swift XRT and UVOT analysis
  14. GRB 080503: 2nd Epoch Chandra X-ray Observations
  15. GRB 080524: Swift-BAT detection of a burst in ground analysis
  16. GRB 080523: Swift-XRT refined analysis
  17. GRB 080523, Swift-BAT refined analysis
  18. GRB 080520: VLT host detection
  19. GRB 080523: VLT optical observations
  20. Swift/UVOT observations of GRB 080523
  21. GRB 080523: Enhanced Swift-XRT position
  22. GRB 080523: Swift detection of a burst
  23. GRB 080515: NIR magnitude correction
  24. GRB 080515: KPNO 4m NIR afterglow detection
  25. GRB080521(?): detection of possible burst from BAT slew data and XRT ToO
  26. GRB 80516: Swift/UVOT Observations
  27. GRB 080515: Swift-XRT position and analysis
  28. GRB 080520, Swift-BAT refined analysis
  29. GRB 080514B: pseudo-z= 1.8 from prompt emission spectrum
  30. GRB 080514B: UVOT Observations
  31. GRB080520: Swift/UVOT observations
  32. GRB 080520: VLT redshift
  33. GRB 080520, GROND observations
  34. GRB 080520: Enhanced Swift-XRT position
  35. GRB 080520: Swift XRT Refined Analysis
  36. GRB 080520: Swift detection of a burst with optical afterglow
  37. GRB 080514B: Suzaku WAM observation of the prompt emission
  38. Konus-Wind observation of GRB 080514B
  39. GRB 080514B: second epoch Swift XRT data confirms the X-ray afterglow
  40. GRB 080503: Further HST imaging
  41. GRB 080517, Swift-BAT refined analysis
  42. GRB 080516, GROND further analysis
  43. GRB 080517: Swift-XRT refined analysis
  44. GRB 080514B: Further NIR observations
  45. GRB 080517: Enhanced Swift-XRT position
  46. GRB080517: Liverpool Telescope Optical Observations
  47. GRB 080517: Swift detection of a burst
  48. GRB 080516, GROND 2nd epoch observations
  49. GRB 080516, GROND observations
  50. GRB080430: optical observations
  51. GRB 080516, SMARTS optical/IR observations
  52. GRB 080516: Swift-XRT Team refined analysis
  53. GRB 080516, Swift-BAT refined analysis
  54. GRB 080516: Enhanced Swift-XRT position
  55. GRB 080514B: NOT observations
  56. GRB 080516: Swift detection of a burst
  57. Errartum: VLA upper limit on GRB 080507
  58. VLA upper limit on GRB 080705
  59. GRB 080514B : redshift estimation
  60. Konus-Wind observation of GRB 080513
  61. IPN triangulation of bright GRB 080513
  62. Swift-BAT refined analysis for Trigger 311603: Galactic source
  63. GRB 080515, Swift-BAT refined analysis
  64. GRB 080514B: KPNO 4m IR observations
  65. GRB 080514B: slow fading behaviour ?
  66. GRB 080514B: Swift-XRT analysis
  67. GRB 080514B, GROND observations
  68. GRB 080515: Swift detection of a burst
  69. GRB 080514B: Finding chart
  70. GRB 080514B: Afterglow candidate
  71. GRB 080514B: Watcher observations
  72. GRB 080430
  73. GRB 080514B: possible AGILE detection at E>50 MeV
  74. GRB 080514B: SuperAGILE/IPN GRB Localization
  75. procesure for GRB Circular
  76. Swift detection of a possible galactic transient
  77. GRB080514: REM NIR & Optical Observations
  78. Konus-Wind observation of GRB 080507
  79. GRB 080319B: Further HST observations and underlying host
  80. GRB 080506: NAYUTA Optical Observation
  81. GRB 080507: Suzaku WAM observation of the prompt emission
  82. GRB 080507: Swift XRT analysis confirms the X-ray afterglow
  83. GRB 080507: Keck photometry
  84. GRB 080507: E Pur Si Muove!
  85. GRB 080503: Chandra Observation of X-ray Rebrightening or Flattening
  86. GRB 080503: Hubble Space Telescope Imaging
  87. GRB080507: Swift/UVOT followup observations
  88. GRB 080507: Optical Afterglow
  89. GRB 080506:Optical observations from HCT
  90. GRB 080507: Swift-XRT position of a possible afterglow
  91. GRB 080506: VLA radio upper limit
  92. GRB 080507: GRB localization by SuperAGILE
  93. GRB 080506: TLS 2nd Epoch - possible light curve break
  94. GRB 080503: Fading in continued Gemini imaging
  95. GRB 080506: Swift XRT refined analysis
  96. GRB080506: Swift/UVOT observations
  97. GRB 080506, Swift-BAT refined analysis
  98. GRB080503, RIMOTS optical upper limit
  99. GRB 080506: Observations from NOT
  100. GRB 080506: optical observation from Ondrejov

Advanced

Download all Circulars as a .tar.gz archive:
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