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"

24385 results found.

  1. GRB050509c (=H3751): An X-Ray Flash Localized By HETE
  2. Swift UVOT Follow-up Observations of GRB 050509B
  3. GRB 050509B: Swift/XRT refined analysis
  4. GRB 050509b: Possible Optical Counterpart
  5. GRB 050509b: Swift-BAT refined analysis of the short hard burst
  6. GRB 050509b: optical observations
  7. GRB 050509B: ROTSE-III Optical Limits
  8. GRB 050505: Keck I-band Magnitude
  9. GRB 050505: early time observations
  10. GRB 050505, simultaneous optical observation
  11. GRB050505: Infrared observations
  12. GRB 050505: Further Swift UVOT observations.
  13. GRB050505: AAVSO observations
  14. GRB 050416b:Swift XRT afterglow upper limits
  15. GRB 050416b:Swift XRT afterglow upper limits
  16. Swift UVOT observation of GRB 050504
  17. GRB 050504, R band Observations
  18. GRB 050504: A long GRB detected with INTEGRAL
  19. GRB (?) 050504: IR Observations, Intriguing Source
  20. Renewal of SGR 1806-20 activity
  21. GRB 050502a: RBO Observations
  22. GRB050502B Swift-BAT refined analysis
  23. Swift UVOT refined analysis
  24. GRB050502B: Optical Limits from ANU 1m
  25. Swift Detection of the Bright Burst GRB050502b
  26. GRB 050502: INTEGRAL results
  27. GRB 050502 - A long GRB detected with INTEGRAL
  28. GRB 050502: ROTSE-III Detection of Possible Counterpart
  29. Swift-BAT Trigger 115881 is not a real GRB
  30. Swift/BAT possible detection of a weak burst GRB050430
  31. GRB 050422: Swift-UVOT observation
  32. GRB 050422: Swift-BAT refined analysis
  33. Swift Detection of GRB 050422
  34. GRB 050421: Swift-UVOT observation
  35. GRB 050421: IR Observations
  36. GRB 050421: Swift-BAT refined analysis
  37. GRB 050421: ROTSE-III Optical Limits
  38. GRB 050421: NIR observations
  39. GRB 050416b: Tentative Swift XRT Position
  40. GRB 050315: potential host galaxy
  41. GRB050326: analysis of the XMM-Newton observation
  42. GRB050418: Null Optical Observations
  43. GRB 050412: Chandra observations
  44. GRB 050418: Swift-BAT refined analysis
  45. GRB 050416b: Swift-BAT refined analysis
  46. GRB 050416: Swift/UVOT refined analysis
  47. IBAS GRB Alert # 2463: not a GRB
  48. GRB050416: Maidanak optical observations
  49. GRB 050416,optical observation
  50. Swift BAT/XRT Detection of GRB 050416
  51. GRB050408: optical observation
  52. GRB 050412: PROMPT VRcIc Observations
  53. GRB 050412: Swift-BAT refined analysis
  54. GRB 050412: LCO Optical Observations
  55. GRB050412: P60 Observations
  56. GRB 050410, optical observations
  57. GRB 050408: Early Optical/Ultraviolet Observations with Swift/UVOT
  58. GRB 050410 R band Optical Observations
  59. GRB050410 : Null detection report
  60. GRB 050408: Swift XRT measurement of possible jet break
  61. GRB050410: MASTER optical observations
  62. GRB 050410: Early observations with Swift-UVOT
  63. Swift-BAT detection of GRB 050410
  64. GRB 050408: WIDGET simultaneous optical observations
  65. GRB 050408: Properties of the Host Galaxy
  66. GRB 050408: Swift XRT analysis
  67. GRB 050408, optical observations
  68. GRB050408: REM NIR and Optical observation
  69. GRB 050408,optical observation
  70. GRB 050408 Optical Observations
  71. GRB 050408: Mercator Optical Observations
  72. GRB 050408: ROTSE-III Optical Limits
  73. GRB 050408 (=H3711): A Long X-Ray-Rich GRB Detected by HETE
  74. GRB050408: MASTER optical observations
  75. Swift-UVOT Optical Counterpart Candidate to XRF 050406
  76. GRB 050406: early Swift XRT analysis results
  77. GRB 050406 BAT refined analysis
  78. GRB 050406: Early observations with Swift-UVOT
  79. GRB050401: Radio observation at 610 MHz with GMRT
  80. GRB050401: Maidanak optical observation
  81. GRB 050401 BAT refined analysis
  82. GRB050401: TNG R-band observation
  83. GRB050401: ROTSE-III Detection of Prompt Optical Counterpart
  84. Swift-BAT detection of GRB 050401
  85. GRB050331: No Afterglow Detected
  86. GRB 050331: Swift UVOT Source
  87. Konus-Wind observation of GRB 050326
  88. GRB050326: optical limit
  89. GRB 050326: Early observations with Swift-UVOT
  90. GRB 050326 BAT refined analysis
  91. Swift-BAT detection of a bright GRB 050326
  92. GRB050319: optical observation, March 20-22
  93. Swift-BAT trigger 112060 is not a real GRB
  94. GRB 050319: ROTSE-III Refined Analysis
  95. GRB 050318: Swift-BAT refined analysis
  96. GRB 050319: Swift-UVOT detection of the afterglow
  97. GRB 050315: Variability Analysis of Swift BAT Time History
  98. GRB050319: BR optical photometry
  99. GRB 050318: SWIFT-UVOT refined analysis
  100. GRB 050319 : Confirmation of optical afterglow decay

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