Skip to main content
New! BOOM Notices and Schema v7.0.0. 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"

5544 results found.

  1. GRB 060502B MDM Follow-up Observation
  2. GRB 060502: Swift detection of a burst with an optical counterpart
  3. GRB 060501: MDM Observations
  4. GRB060501: Super-LOTIS observations
  5. GRB060501: P60 imaging and afterglow candidate
  6. GRB060501: Swift XRT position
  7. GRB 060428B: KAIT observations
  8. GRB060427:MASTER optical limit
  9. GRB 060428B: Swift detection of a burst
  10. GRB 060428: Swift detection of a burst
  11. GRB 060421: TTT Observations
  12. GRB(?) 060421: Swift detection of a burst
  13. GRB 060418: JHKs PAIRITEL Observations of Afterglow
  14. GRB 060413: XRT refined analysis
  15. SGR 1900+14: BAT observations
  16. SGR 1900+14: bright burst detected by Konus-Wind on March 28
  17. SGR 1900+14: Swift-BAT detection of a cluster of outbursts
  18. GRB 060322: Confirmation of Swift XRT afterglow
  19. GRB 060322: Swift-BAT detection of a 200-sec burst
  20. GRB060219: optical observation
  21. GRB 060306: Swift detection of a bright burst
  22. GRB 060218/SN 2006aj: WIRO optical observations
  23. GRB 060211B: Skynet Observations
  24. GRB 060213: optical afterglow candidate
  25. GRB060213: Swift XRT observations and possible afterglow candidate
  26. GRB060213: MASTER final result
  27. GRB060213:_MASTER_optical_observation
  28. GRB 060213: IPN localization
  29. GRB060121: optical observations
  30. GRB 060211: ROTSE-III Optical Limits
  31. GRB 060211: Swift detection of a long burst
  32. GRB060210: Swift XRT Refined Analysis
  33. GRB 060210: Swift detection of a burst
  34. Swift-BAT trigger 180931 is not a GRB
  35. GRB060209: RTT150 optical observations
  36. GRB 060209 : TAROT optical observation
  37. GRB060209A: MASTER optical observation
  38. GRB 060206: TTT Observations
  39. GRB 060206: Super-LOTIS observations
  40. GRB060204C: optical observation
  41. GRB060204B, optical observation
  42. GRB 060202: GETS observation
  43. GRB060202, optical observation
  44. GRB 060202: Swift/UVOT upper limits
  45. GRB 060121: Gemini Late-time Observations
  46. GRB 060130, SMARTS optical observations
  47. GRB 060130: FRAM optical observations
  48. GRB060124: detailed XRT analysis
  49. GRB 060116: MARGE optical observations
  50. GRB 060121: candidate optical counterpart
  51. GRB060121 - SDSS pre-burst observations
  52. GRB 060116: IR Candidate Afterglow
  53. GRB 060116: Swift-BAT detection of a burst
  54. GRB 060115: Swift/UVOT upper limits
  55. GRB 060115: Swift detection of a burst
  56. GRB060108: Faulkes North afterglow evidence
  57. GRB 060110: MARGE observations
  58. GRB 060111B: Swift detection of a burst
  59. GRB060110, optical observation
  60. GRB 060109: Swift/UVOT upper limits
  61. GRB060109, optical observation
  62. GRB 060109: Swift Detection of a long burst
  63. GRB060108: SDSS pre-burst observations
  64. GRB 060105: Mitsume optical observations
  65. GRB060105, optical observation
  66. GRB060105 : Kiso optical observation
  67. GRB051211B: optical observations
  68. GRB 051221B: ROTSE-III Optical Limits
  69. Refined analysis of the SWIFT J1626.6-5156
  70. Swift detection of an RS CVn flare star
  71. GRB051105: optical observations
  72. Possible resuming of the SGR 1806-20 activity
  73. GRB051117A : XRT refined analysis
  74. GRB 051117B: Swift detection of a burst
  75. GRB 051109B : Nainital upper limits
  76. GRB 051114: Swift-BAT refined analysis
  77. GRB 051114: Swift-BAT detection of a short burst
  78. GRB 051105a: GETS optical limit
  79. GRB 051109b: GETS observation
  80. GRB 051109A: KAIT optical observations
  81. GRB 051109A: Swift-UVOT Observations
  82. GRB 051109B Kiso optical follow-up observation
  83. GRB 051109a: IR Photometry and Astrometry
  84. GRB 051109A: ROTSE-III Decline rate for Optical Counterpart
  85. GRB 051109a: IR Detections
  86. GRB051103: MASTER: OT limit and host galaxy candidates
  87. GRB051103:_MASTER_optical_observations
  88. IPN triangulation and Konus spectrum of the bright short/hard GRB051103
  89. GRB 051105: Optical limit
  90. GRB051028:MASTER observations
  91. GRB051021a: optical observations
  92. GRB051021A: Swift XRT refined analysis
  93. GRB051022,optical observation
  94. GRB 051022: Optical observations
  95. GRB 051021B: Swift detection of a burst
  96. GRB051021: Swift XRT analysis
  97. GRB 051016B: Swift detection of a soft burst
  98. GRB051006: optical observations
  99. GRB050805A: Rc optical observations
  100. GRB 051006: XRT refined analysis

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