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"

32494 results found.

  1. GRB061126: Optical afterglow observations from MIRO
  2. GRB 061126 : SDSS Pre-Burst Observations
  3. GRB 061126: Swift-XRT refined analysis
  4. GRB 061126: Swift/UVOT Observations
  5. GRB 061126, Swift-BAT refined analysis
  6. GRB 061126: SARA Observations
  7. GRB 061126: Early Detection of the IR Afterglow
  8. GRB 061126: Faulkes Telescope North Optical Observations
  9. GRB 061121: MDM Continued Monitoring
  10. GRB 061122: Confirmation of X-ray/Optical Afterglow
  11. GRB 061121: MDM Continuing Optical Decay
  12. GRB061121: optical observations
  13. GRB 061122: Candidate Optical Afterglow
  14. GRB 061121: Ep,i - Eiso correlation
  15. GRB 061121: MDM Optical Decay
  16. GRB061122: Swift/UVOT Optical Observations
  17. GRB 061121: ART detection in Ic
  18. GRB061121: P60 Observations
  19. Radio detection of GRB 061121
  20. GRB061122: Swift-XRT position
  21. Konus-Wind observation of GRB 061122
  22. GRB 061121: MDM Optical Observations
  23. GRB 061121 declared "Burst of Interest" by Swift team
  24. RHESSI Spectrum of GRB061121
  25. Konus-Wind and Konus-A observations of GRB 061121
  26. INTEGRAL results on GRB 061122
  27. GRB 061121: Swift/UVOT Observations
  28. GRB 061121: Swift-XRT Team Refined Analysis
  29. GRB 061121, Swift-BAT refined analysis
  30. GRB061121, optical observation
  31. GRB 061121: Optical observation at the KANATA 1.5m telescope
  32. GRB 061121: Faulkes Telescope North Optical Observation
  33. GRB061121: Spectroscopic Redshift
  34. GRB 061121: ROTSE-III Confirmation of Optical Counterpart
  35. GRB 060605: NIR Observations
  36. GRB 050915B: optical afterglow
  37. GRB 060111B: Swift UVOT Refined Magnitudes
  38. GRB061110A: Correction to GCN5817
  39. GRB 061110A: refined R-band analysis
  40. GRB 061110B: NIR Observations
  41. Swift/UVOT Upper Limits for GRB061110b
  42. Swift/UVOT Upper Limits for GRB061110a
  43. GRB 061110B: Swift XRT refined analysis
  44. GRB 061110B, Swift-BAT refined analysis
  45. GRB 061110B: VLT redshift
  46. GRB 061110B: NOT optical observations
  47. GRB 061110A: Swift XRT refined analysis
  48. GRB 061110B: Swift/XRT position
  49. GRB 061110B : Liverpool Telescope Optical Afterglow Detection
  50. GRB 061110A, Swift-BAT refined analysis
  51. GRB 061110: ROTSE-III Optical Limits
  52. Swift-BAT Trigger 237821 is a Cosmic Ray Shower event
  53. GRB 061109: optical observation
  54. GRB061028: MAGIC telescope GeV observation
  55. GRB 061007: Third Epoch ATCA Radio Observations
  56. GRB061019: second epoch CrAO observations
  57. GRB 061028: Swift/XRT Astrometry Correction
  58. GRB 061102: Swift/UVOT Magnitude Upper Limits
  59. GRB 061102, XRT refined analysis
  60. GRB 061004: Further VLT/NTT observations
  61. Swift-BAT Trigger 236481 is a Cosmic Ray Shower event
  62. GRB061102B: Super-LOTIS observations
  63. GRB 061028: Optical R passband observations
  64. GRB 061102, Swift-BAT refined analysis
  65. GRB 061028: VLA Observation
  66. GRB 061004: Swift/XRT Astrometry Correction
  67. GRB 060801: Swift/XRT Astrometry Correction
  68. GRB 061028: Futher P200 Observations
  69. GRB 061028: MDM Observations
  70. GRB 061028: P200 Observations
  71. GRB 061028: SARA upper limit
  72. GRB 061028: z band imaging
  73. GRB061028: XRT refined analysis
  74. GRB 061028: Swift/UVOT Observations
  75. GRB 061028, Swift-BAT refined analysis
  76. GRB 061027, Swift refined analysis of a possible burst
  77. GRB061025: ROTSE-III Confirmation of Optical Counterpart
  78. GRB061025: Swift XRT refined analysis
  79. GRB061025: Swift/UVOT observations
  80. GRB 061019: MITSuME upper limits
  81. GRB 061025: REM observations
  82. GRB 061025: Gemini-S observations
  83. GRB061025: Swift XRT position
  84. GRB 061025: ROTSE-III Optical Limits
  85. Swift XRT boresight update
  86. GRB 061021, Swift-BAT Lag analysis
  87. Konus-Wind observation of GRB 061021
  88. GRB 061021 - VLT spectrum without lines
  89. GRB 061021: Swift-XRT refined analysis
  90. GRB 061021: Swift/UVOT Observation
  91. GRB 061021, Swift-BAT refined analysis
  92. GRB 061019: Super-LOTIS upper limit
  93. GRB060904b: optical observations
  94. GRB061019: optical observations
  95. GRB061019: optical observations
  96. GRB 061019: SARA upper limit
  97. GRB 060930: MARGE Optical Limits
  98. GRB 061019: Swift/UVOT upper limit
  99. GRB 061019: SMARTS afterglow confirmation
  100. GRB061019: Swift XRT refined analysis

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