Skip to main content
Updates to LVK & CHIME Notices, Schema v7.2.3! 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"

28068 results found.

  1. GRB 051221: Swift detection of a bright short burst
  2. Refined analysis of the Swift-BAT detection of the RS CVn star II Peg
  3. GRB 051211B: optical afterglow
  4. Swift detection of an RS CVn flare star
  5. GRB051211A: possible optical candidate
  6. GRB 051215: Swift detection of a possible burst
  7. GRB051211B: Probable radio afterglow
  8. GRB051105: optical observations
  9. GRB051211B: XRT refined analysis
  10. GRB 051213: Swift-BAT detection of a burst
  11. GRB051211B, RBO optical observations
  12. GRB 051211B: Swift/UVOT upper limits
  13. GRB 051211B: Swift XRT confirmation of the afterglow
  14. GRB051211B: Liverpool Telescope observation
  15. GRB 051211b: RTT150 optical observations
  16. GRB051211b: P60 Observations
  17. GRB 051211A and GRB051211B: BOOTES simultaneous observations
  18. GRB 051211B: Swift XRT Observations
  19. GRB 051210: Swift/UVOT upper limits
  20. GRB 051211B: a possible optical detection by TAROT
  21. GRB 051211: Swift XRT upper limit
  22. GRB 051210: Optical imaging from Las Campanas
  23. GRB 051210: SALT detection limit
  24. GRB 051210: BAT further refined analysis of the short burst
  25. GRB 051210: Swift XRT refined analysis
  26. GRB 051210: FRAM early limit
  27. GRB051210: Swift UVOT Observation
  28. GRB 051210: A short GRB in a cluster?
  29. GRB 051210: Swift detection of a burst
  30. Swift XRT positions
  31. GRB051117B: optical observation
  32. GRB 051127: Swift-BAT detection of a possible burst
  33. GRB051117B: Swift XRT refined analysis
  34. GRB051117b: No Swift/UVOT Detection
  35. GRB 051117A: Swift/UVOT Detection of an Afterglow: Correction
  36. GRB 051117A: Swift/UVOT Detection of an Afterglow
  37. GRB 051109B: GAO 150cm telescope Optical limit
  38. GRB 051109A : GAO 150cm telescope Rc-band detection
  39. GRB 051117A and B: Radio Observations
  40. GRB 051117B: R and I observations of possible host galaxy
  41. GRB 051117b: NIR observations
  42. GRB051117A : XRT refined analysis
  43. GRB 051117B,optical observation
  44. GRB 051117B: Lulin R and I band observation
  45. GRB 051117B: Optical observations
  46. GRB051117B: Swift XRT position
  47. GRB 051117B: Swift detection of a burst
  48. GRB 051117: Swift detection of a bright burst
  49. GRB051114: results of the Swift-XRT observation
  50. GRB 051109B : Nainital upper limits
  51. GRB050925: analysis of the XMM-Newton observation
  52. GRB051109A optical observations
  53. GRB 051114: Swift-BAT detection of a short burst
  54. GRB 051111: Radio afterglow
  55. GRB 051113: Swift-BAT detection of a burst
  56. GRB 051109A Milagro GeV/TeV Observations
  57. GRB/SGR 050925: XMM-Newton ToO observation
  58. GRB051111: Swift/UVOT Observations
  59. GRB 051111A : R-band temporal decay index based on Lulin
  60. GRB051111: XRT preliminary analysis
  61. GRB 051111A : Lulin BVRI multi band afterglow observation
  62. GRB 051111a: Afterglow fading in Ic
  63. GRB051111: Super-LOTIS Early Detection
  64. Faulkes Telescope R-band detection of GRB051111
  65. GRB051111: Swift-BAT detection of a bright burst
  66. GRB 051111A: ROTSE-III Detection of Possible Counterpart
  67. GRB 051008 Tautenburg Supernova Search
  68. GRB 051109B. Radio Observations
  69. GRB 051109A
  70. GRB051109A - radio observations
  71. GRB 051109A: KAIT optical observations
  72. GRB 051109B: ROTSE-III Optical Limits
  73. GRB051109B: no UVOT source detected
  74. GRB051109B: XRT refined analysis
  75. GRB 051109B : Lulin Optical Observations
  76. GRB 051109A : Lulin BVRI Optical afterglow observation
  77. GRB051109A: further steepening in the X-ray light curve
  78. GRB051109A: XRT refined analysis
  79. GRB 051109a: BOOTES R & I-band detection of the early afterglow
  80. GRB051109B: XRT position
  81. GRB 051109B: Swift detection of a burst
  82. GRB 051109: HET Optical Spectrum and Absorption Redshift
  83. GRB 051109: PROMPT Detections
  84. GRB 051109: Rc and Ic observations
  85. GRB051109: Early Super-LOTIS Detection
  86. GRB 051109a: MDM Observations
  87. GRB051109: Swift detection of a burst
  88. GRB 051109a: IR Detections
  89. GRB 051109: ROTSE-III Detection of Possible Counterpart
  90. GRB051105B: Swift/XRT upper limit
  91. GRB051028: Swift-XRT refined analysis
  92. GRB 051105A, 2nd epoch optical observations
  93. GRB 051105a: MDM Observations
  94. GRB 051105A: TNG optical observations
  95. GRB051105A: Swift/UVOT Observations
  96. GRB 051105A, radio observations
  97. GRB 051105A, optical observations
  98. XRT observations of GRB 051105A
  99. GRB 051105b: ART optical limits
  100. GRB 051105: Optical limit

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