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"

19551 results found.

  1. GRB051103: Radio Observations
  2. GRB 051109A Milagro GeV/TeV Observations
  3. GRB051111: Swift/UVOT Observations
  4. GRB 051109A Optical Observations
  5. GRB 051111a: IR photometry
  6. GRB 051109B. Radio Observations
  7. GRB 051109A
  8. GRB051109A - radio observations
  9. GRB 051109A: Swift-UVOT Observations
  10. GRB051109B: no UVOT source detected
  11. GRB 051109B: Super-LOTIS Observations
  12. GRB051105B: REM Optical observation
  13. GRB 051109: Rc and Ic observations
  14. GRB 051109a: IR Photometry and Astrometry
  15. GRB051109: Swift detection of a burst
  16. GRB 051109a: IR Detections
  17. GRB051105B: Swift/XRT upper limit
  18. GRB051105B: Swift/UVOT upper limit
  19. GRB051103: optical observations
  20. GRB 051105a, observation from Naini Tal and OSN
  21. GRB 051105a: MDM Observations
  22. GRB 051105A: TNG optical observations
  23. GRB051105A: Swift/UVOT Observations
  24. GRB 051105A, radio observations
  25. XRT observations of GRB 051105A
  26. GRB 051105: Swift-BAT improved refined analysis
  27. GRB 051105: Swift detection of a short burst
  28. Recent GRB UBVRcIc field photometry
  29. GRB051028 SARA Observation
  30. GRB051028: Swift/UVOT upper limits
  31. GRB051028: Swift XRT Position
  32. SGR 1806-20: continued moderate activity seen with INTEGRAL
  33. GRB051021B: Swift/UVOT Upper limits
  34. GRB 051021, Optical Observations
  35. GRB051012: Swift-XRT analysis
  36. GRB 051022: Swift/UVOT Upper Limits
  37. GRB051022: Radio Counterpart
  38. GRB051022: IR observations
  39. GRB051021A: Swift XRT refined analysis
  40. GRB051022: Optical Observations
  41. GRB051021b: Magellan IR Imaging
  42. GRB051022: Swift XRT Position
  43. GRB 051021: P200 Ks Observations
  44. GRB 051022 (=H3950): SXC Flight Localization is Valid
  45. GRB051021: Swift/UVOT Upper Limits
  46. GRB 051022: SSO40 Optical Observations
  47. GRB051022,optical observation
  48. GRB 051021,optical observation
  49. GRB 051021B: Swift detection of a burst
  50. Swift-BAT triggered on a posible CR Shower or possible GRB
  51. Afterglow candidate of GRB 051016B observed at Lulin
  52. GRB 051016A: Swift/UVOT upper limits
  53. GRB 051016B: refined analysis of the Swift/XRT data
  54. GRB 051016B: Swift/UVOT detection
  55. GRB 051016B,optical observation
  56. GRB 051016B: Swift detection of a soft burst
  57. GRB051016 XMM-Newton observation
  58. GRB051016: Swift XRT refined analysis.
  59. GRB 051016: PROMPT Observations
  60. GRB051016: Swift detection of a burst
  61. GRB051006: optical observations
  62. GRB 051012: Swift-BAT detection of burst yesterday
  63. GRB 051006: Swift/UVOT Upper Limits
  64. GRB051008: optical candidate
  65. GRB051008: optical observation
  66. GRB051008: Radio Observation
  67. GRB 051008: Swift XRT position
  68. GRB 051008, optical observations
  69. GRB 051008: early Swift XRT analysis
  70. GRB 051008: Swift UVOT Candidate
  71. GRB 051006: P60 Observations
  72. GRB 051006: XRT refined analysis
  73. Swift-BAT trigger 158700 is a probable Cosmic Ray Shower Event
  74. GRB051006: Refined analysis of the Swift-BAT burst
  75. GRB 051006: XRT position
  76. GRB051006: Swift detection of a burst
  77. GRB 050906, summary of radio observations
  78. GRB051001: Swift UVOT Upper Limits
  79. GRB 051001, optical observations at Mt. John
  80. GRB 051001: AAT infra-red observations
  81. GRB 051001: Swift Detection of a Burst
  82. GRB050908: optical observations
  83. GRB 050820A: NIR photometry at the TNG
  84. GRB/SGR 050925: IR Observations
  85. GRB050925: Swift UVOT upper limits
  86. Refined analysis of the Swift-BAT soft short burst
  87. GRB050925: Faulkes Telescope North R-band limit
  88. GRB050925: Swift-BAT detection of a short burst
  89. GRB050922B: Swift UVOT early upper limits.
  90. INT 2.5m limit for GRB050922B
  91. GRB 050922C: Swift XRT refined analysis
  92. GRB 050922C: Swift-BAT refined analysis
  93. GRB 050922C: optical obserations
  94. GRB 050922C: NOT optical observations
  95. GRB 050922C: Swift detection of a bright burst
  96. GRB 050922B: ROTSE-III Optical Limits
  97. GRB 050922B,optical observation
  98. GRB050922B: Swift-BAT detection of a weak long burst
  99. GRB050820B: analysis of the XMM-Newton observation
  100. GRB050916: Swift/UVOT Upper Limits

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