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"

19530 results found.

  1. GRB 051021B: Refined analysis of the Swift-BAT burst
  2. GRB051021B: Swift XRT Position
  3. GRB 051021B: Swift detection of a burst
  4. GRB051021: Swift XRT analysis
  5. GRB051021.63
  6. Swift-BAT trigger 160640 is not a real GRB
  7. Swift-BAT trigger 160619 is not a GRB
  8. Swift-BAT triggered on a posible CR Shower or possible GRB
  9. GRB 051016A: Swift/UVOT upper limits
  10. GRB 051016B: refined analysis of the Swift/XRT data
  11. GRB 051016B: Swift/UVOT detection
  12. GRB 051016B : Optical follow-up at Lulin
  13. GRB 051016B: Refined analysis of the Swift-BAT burst
  14. GRB 051016B: Swift detection of a soft burst
  15. GRB 051016: Swift-BAT refined analysis
  16. GRB051016 XMM-Newton observation
  17. GRB051016: Swift XRT refined analysis.
  18. GRB051016: Swift detection of a burst
  19. Photometric calibration of Swift/UVOT and Re-analysis of Swift/UVOT GRB 050922C data
  20. GRB 051012: Swift-BAT detection of burst yesterday
  21. Swift trigger 159578 is not a burst
  22. Swift-BAT Trigger 159578 is a possible burst
  23. GRB050805A: Rc optical observations
  24. GRB 051006: Swift/UVOT Upper Limits
  25. GRB 051008 - a low redshift low-luminosity burst?
  26. GRB051008: Swift XRT refined analysis
  27. GRB051008 - Swift UVOT upper limits
  28. Konus-Wind observation of GRB 051008
  29. GRB051008: Final refined analysis of the Swift-BAT burst
  30. GRB 051008: R-band upper limit
  31. GRB051008: Refined analysis of the Swift-BAT burst
  32. GRB 051008: Swift XRT position
  33. GRB 051008: early Swift XRT analysis
  34. GRB 051008: Swift UVOT Candidate
  35. GRB051008: Swift-BAT detection of a bright burst
  36. GRB 051006: XRT refined analysis
  37. Swift-BAT trigger 158700 is a probable Cosmic Ray Shower Event
  38. GRB 051006: optical observations at Sierra Nevada
  39. GRB051006: Refined analysis of the Swift-BAT burst
  40. GRB 051006: XRT position
  41. GRB051006: Swift detection of a burst
  42. Swift-BAT triggers 158261 and 158262 Retraction
  43. GRB051001: Swift UVOT Upper Limits
  44. GRB 050925: Second Epoch WSRT Radio Observations
  45. GRB 051001: Swift XRT refined analysis
  46. GRB 051001, optical observations at Mt. John
  47. GRB 051001: I-band limit
  48. GRB 051001: Swift-BAT refined analysis
  49. GRB 051001: Swift Detection of a Burst
  50. GRB 051001: ROTSE-III Optical Limits
  51. GRB050922B: optical limit
  52. GRB050925: Swift/XRT limits
  53. GRB/SGR 050925: IR Observations
  54. GRB050922C - Swift UVOT preliminary analysis
  55. GRB 050925: WSRT Radio Observations
  56. GRB050925: Swift UVOT upper limits
  57. Refined analysis of the Swift-BAT soft short burst
  58. GRB050925: Faulkes Telescope North R-band limit
  59. GRB050925: Swift-BAT detection of a short burst
  60. GRB 050922B: Correction to BAT refined analysis, longer burst
  61. GRB050922B: refined XRT analysis
  62. Konus-Wind observation of GRB 050922C
  63. GRB050922B: Swift UVOT early upper limits.
  64. GRB 050922B: optical limit
  65. GRB 050922C: Swift XRT refined analysis
  66. HETE Fregate observations of GRB 050922C
  67. GRB 050922C: Swift-BAT refined analysis
  68. GRB 050922B: Swift-BAT refined analysis
  69. GRB050922C: optical observations
  70. GRB 050922C: Absorption redshift from the Nordic Optical Telescope
  71. GRB 050922C: optical obserations
  72. GRB 050922C: NOT optical observations
  73. GRB 050922A: Analysis of Swift/XRT TOO observation
  74. GRB 050922C: Swift detection of a bright burst
  75. GRB 050922C: ROTSE-IIId Refined Analysis
  76. GRB 050922C: ROTSE-III Detection of Possible Counterpart
  77. GRB 050922B: ROTSE-III Optical Limits
  78. GRB 050922B,optical observation
  79. GRB050922B: Swift-BAT detection of a weak long burst
  80. GRB050918: Possible Swift/XRT detected afterglow
  81. GRB050820B: analysis of the XMM-Newton observation
  82. GRB050916: Swift/UVOT Upper Limits
  83. GRB 050916: Swift-BAT refined analysis
  84. Swift-BAT trigger 155764 is not a GRB
  85. Swift-BAT trigger 155764 is probably not a GRB
  86. Swift trigger 155764: bad XRT centroid
  87. Swift-BAT trigger 155535 is definitely not a GRB
  88. GRB050916 : Swift-XRT refined analysis
  89. GRB 050916: XRT position
  90. GRB 050915B: Swift-BAT refined analysis
  91. GRB 050915B: Swift/UVOT Upper Limits
  92. GRB050916: Swift-BAT detection of a long weak burst
  93. GRB 050915B: XRT position
  94. GRB050915B: Swift-BAT detection of a long bright burst
  95. GRB050915: Swift/UVOT upper limits
  96. GRB 050915: KAIT optical limit
  97. GRB 050915: IR Observations
  98. GRB 050915: Swift XRT refined analysis
  99. GRB 050915: Swift-BAT refined analysis
  100. GRB050915, 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