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"

35254 results found.

  1. GRB 051221: Continued fading of optical afterglow
  2. GRB 051221B: Refined analysis of the Swift-BAT burst
  3. Possible GRB 051221B: MDM Optical Detection
  4. GRB 051221A: RAPTOR Fading Counterpart Constraint
  5. GRB 051221B: BOOTES optical observations.
  6. Possible GRB 051221B: Swift XRT position
  7. GRB 051211A: Evidence This Is a Short Burst from Analysis of Spectral
  8. Swift-BAT detection of a possible burst
  9. GRB 051221: Discovery of fading optical afterglow
  10. GRB 051221: Swift XRT refined analysis
  11. GRB 051221: Swift/UVOT upper limits
  12. GRB 051221: Possible nearby cluster
  13. GRB 051221: No variability in Gemini data
  14. GRB 051221: Correction to GCN #4368
  15. GRB 051221: Gemini observations
  16. GRB 051221: Improved astrometry of the IR counterpart
  17. GRB051221: K-band source
  18. GRB 051221: XRT position
  19. GRB 051221: Refined analysis of the Swift-BAT short hard burst
  20. GRB 051221: IR Observations at GRB+1hr
  21. GRB 051221: Swift detection of a bright short burst
  22. Swift-BAT discovery of hard x-ray transient SWIFT J1626.6-5156
  23. Refined analysis of the Swift-BAT detection of the RS CVn star II Peg
  24. GRB 051211B: optical afterglow
  25. Swift detection of an RS CVn flare star
  26. GRB051211A: possible optical candidate
  27. Swift Trigger 172767 is not a GRB
  28. GRB 051215: near-infrared observations
  29. GRB051215 - SDSS pre-burst observations
  30. GRB 051215: Swift detection of a possible burst
  31. GRB 051215: A short GRB in a cluster?
  32. GRB051105: optical observations
  33. GRB 051213: Swift-BAT refined analysis
  34. GRB 051211B, optical observation
  35. GRB 051213: Swift-BAT detection of a burst
  36. GRB 051211a: RTT150 optical observations
  37. GRB051211B, RBO optical observations
  38. GRB 051211A: Swift/UVOT upper limits
  39. GRB 051211B: Swift/UVOT upper limits - correction
  40. GRB 051211B: Swift/UVOT upper limits
  41. GRB 051211A,optical observation
  42. GRB 051211B: Swift XRT confirmation of the afterglow
  43. GRB051211B: Liverpool Telescope observation
  44. GRB 051211b: RTT150 optical observations
  45. GRB 051211A and GRB051211B: BOOTES simultaneous observations
  46. GRB 051211B: Swift XRT Observations
  47. GRB 051210: Swift/UVOT upper limits
  48. GRB 051210: Magellan Imaging
  49. GRB 051211: TAROT optical limits
  50. GRB 051211B: a possible optical detection by TAROT
  51. GRB 051211B: a long GRB detected by INTEGRAL
  52. GRB 051211: Swift XRT upper limit
  53. GRB 051211:IAC80 optical observations
  54. HETE SXC localization of GRB 051211 (=H3979)
  55. GRB 051210: Optical imaging from Las Campanas
  56. GRB 051210: SALT detection limit
  57. GRB 051210: BAT further refined analysis of the short burst
  58. GRB 051210: Swift XRT refined analysis
  59. GRB 051210: FRAM early limit
  60. GRB 051210: Swift-BAT refined analysis of a short burst
  61. GRB 051210: A short GRB in a cluster?
  62. GRB 051210: Swift detection of a burst
  63. IPN observations of SGR1806-20
  64. An extraordinary long burst on December 3 from SGR1806-20
  65. IBAS Alert 2706 : not a real GRB
  66. GRB051117B: optical observation
  67. GRB051111: optical observaion
  68. Swift-BAT trigger 165579 is not a GRB
  69. GRB 051127: Swift-BAT detection of a possible burst
  70. GRB051117b: No Swift/UVOT Detection
  71. GRB 051117A: Swift/UVOT Detection of an Afterglow: Correction
  72. GRB 051117A: Swift/UVOT Detection of an Afterglow
  73. GRB051111: Suzaku WAM observation of the prompt emission
  74. GRB051008: Suzaku WAM observation of the prompt emission
  75. GRB 051109B: GAO 150cm telescope Optical limit
  76. GRB 051109A : GAO 150cm telescope Rc-band detection
  77. GRB 051021 Optical Observations
  78. GRB 051117B: MARGE Optical Limits
  79. GRB 051117A and B: Radio Observations
  80. GRB 051117B: R and I observations of possible host galaxy
  81. GRB 051117b: NIR observations
  82. GRB 051117A: Refined analysis of the Swift-BAT burst
  83. GRB 051117B: Refined analysis of the Swift-BAT burst
  84. GRB 051117B,optical observation
  85. GRB 051117B: Lulin R and I band observation
  86. GRB 051117B: Optical observations
  87. GRB 051117B: ROTSE-III Optical Limits
  88. GRB 051117B: Swift detection of a burst
  89. GRB 051117: Swift detection of a bright burst
  90. GRB 051028 Optical Observations
  91. GRB 051109B : Nainital upper limits
  92. GRB 051114: Radio Observations
  93. GRB 051114: Swift-BAT refined analysis
  94. GRB051109A optical observations
  95. GRB 051114: Swift-BAT detection of a short burst
  96. GRB 051111: Further spectroscopic analysis
  97. GRB 051111: Radio afterglow
  98. GRB 051113: Swift-BAT refined analysis
  99. GRB 051113: Swift-BAT detection of a burst
  100. GRB 051111: AEOS optical observations

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