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"

27396 results found.

  1. GRB 131028A: Fermi GBM detection
  2. Swift 575905/GRB 131026A: optical observations
  3. Swift-BAT Trigger 575905 is probably not a real source
  4. GRB 131024B: AAO optical upper limit
  5. GRB 131024B: Mondy optical upper limits
  6. Swift Trigger 575905/ GRB 131026A: MITSuME Okayama and Ishigakijima Optical upper limits
  7. Swift Trigger 575905/possible GRB 131026A: Swift-XRT observations
  8. GRB 131026A: TAROT La Silla observatory optical observations
  9. Swift Trigger 575905: a possible GRB
  10. GRB 131024B, Swift-BAT refined analysis
  11. GRB 131024B: Fermi GBM observation
  12. GRB 131024B: RATIR Optical and NIR Observations
  13. GRB 131024B: Swift/UVOT Upper Limits
  14. GRB 131024B: Swift-XRT refined Analysis
  15. GRB 131024B: Nanshan optical upper limit
  16. GRB 131024A: Swift/UVOT Upper Limits
  17. GRB 131024B: Enhanced Swift-XRT position
  18. GRB 131024A: GROND upper limits
  19. GRB 131024A: Swift-XRT refined Analysis
  20. GRB 131024B: Swift detection of a burst
  21. GRB 131024A, Swift-BAT refined analysis
  22. GRB 131024A: Skynet R-COP optical observations
  23. GRB 131024A: Enhanced Swift-XRT position
  24. IPN triangulation of GRB 131011B (Swift Trigger 574266)
  25. GRB 131024A: Swift detection of a burst
  26. GRB 131014A: RATIR Optical/NIR Afterglow Retraction
  27. IPN Triangulation of GRB 131014A
  28. GRB 131018B: Swift/UVOT Upper Limits
  29. GRB 131018B: Fermi GBM observation
  30. GRB 131018A: RATIR Optical and NIR Observations
  31. GRB 131018A: Swift/UVOT Upper Limits
  32. GRB 131018A: Swift-XRT refined Analysis
  33. GRB 131018A, Swift-BAT refined analysis
  34. GRB 131018A: Enhanced Swift-XRT position
  35. GRB131018A, optical observations
  36. GRB 131018A: Swift detection of a burst
  37. GRB 131014A: Suzaku WAM observation of the prompt emission
  38. GRB 131014A: GROND observations
  39. GRB 131014A: RATIR Optical/NIR Afterglow Confirmation
  40. Fermi GBM data availability during U.S. government shutdown
  41. GRB 131014A: Swift-XRT refined Analysis
  42. GRB 131011A: Swift/UVOT Upper Limits
  43. GRB 131014A: Swift/UVOT Upper Limits
  44. GRB 131014A: RATIR Optical and NIR Observations
  45. GRB 131014A: Enhanced XRT position
  46. GRB 131014A: NOT afterglow candidate
  47. GRB 131014A: Nanshan optical observations
  48. GRB 131014A: Fermi-LAT detection
  49. GRB 131014A: Fermi GBM detection
  50. Swift-XRT detection of iPTF 13dsw/Fermi403206457
  51. GRB 131011A: GROND afterglow observations
  52. Fermi403206457: continued P60 observations and fading behavior
  53. Fermi403206457: Weihai optical upper limit
  54. Trigger 574266 is not a Swift detection of a known source
  55. GRB 130831A: Continued RATIR Optical and NIR Observations
  56. GRB 131004A: Skynet PROMPT/DSO-14 upper limits
  57. GRB 131004A, Swift-BAT refined analysis
  58. GRB 131004A: Swift/UVOT Detection
  59. GRB 131004A: RATIR Optical and NIR Upper Limits
  60. GRB 131004A: Swift-XRT refined Analysis
  61. GRB 131004A: GROND observations of the afterglow
  62. GRB 131004A: Enhanced Swift-XRT position
  63. GRB 131004A: Liverpool Telescope optical afterglow observations
  64. GRB 131004A: TNG optical afterglow confirmation
  65. GRB 131004A: optical afterglow from the NOT
  66. GRB 131004A: Swift detection of a burst (may be short)
  67. GRB 131002A, Swift-BAT refined analysis
  68. GRB 130925A/Sw J0244-2609: mm observations at PdBI
  69. GRB 131002B, Swift-BAT refined analysis
  70. GRB 131002B: GROND upper limits
  71. GRB 131002B: Swift-XRT Refined Analysis
  72. GRB 131002B: Swift/UVOT Upper Limits
  73. GRB 131002A: Swift/UVOT Detection
  74. GRB 131001A, Swift-BAT refined analysis
  75. GRB 131002A: Swift-XRT refined Analysis
  76. GRB 131002B: Enhanced Swift-XRT position
  77. Swift J1242.9-3530, Swift-BAT refined analysis
  78. GRB 131001A: Swift UVOT and XRT Upper Limits
  79. GRB 131002A: Enhanced Swift-XRT position
  80. NuSTAR observations of GRB 130925A
  81. GRB 131002B: Swift detection of a burst
  82. GRB 131002A: Swift detection of a burst
  83. GRB 131002A: Faulkes Telescope North optical afterglow
  84. US Government shutdown may impact GRB operation of GCN
  85. GRB 130929A: Swift/UVOT Upper Limits
  86. GRB 130831A: Continued RATIR Optical and NIR Observations
  87. GRB 130929A: Swift-XRT refined Analysis
  88. GRB 130929A, Swift-BAT refined analysis
  89. GRB 130929A: Enhanced Swift-XRT position
  90. GRB 130929A: TAROT La Silla observatory optical observations
  91. GRB 130929A: Swift detection of a burst
  92. Fermi LAT Upper Limits on GRB 130925A
  93. GRB 130925A: Swift/UVOT Upper Limits
  94. GRB 130925A: optical upper limit
  95. GRB 130925A: Continued RATIR Optical and NIR Observations
  96. Konus-Wind observation of GRB 130925A
  97. Observation of possible GRB/TDE 130925A by INTEGRAL/SPI-ACS: three activity episodes
  98. GRB 130925A: RATIR Optical and NIR Observations
  99. GRB 130925A Swift-BAT refined analysis
  100. Fermi GBM detection of GRB 130925A and a possible precursor

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