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"

28048 results found.

  1. GRB 061004: Swift detection of a burst
  2. GRB 060928: Suzaku/WAM observation of the prompt emission
  3. IGR J08408-4503 (= V* LM Vel): Swift detection of a transient
  4. GRB 060928: Swift observations
  5. IPN triangulation of GRB060928 (long, exceptionally bright)
  6. GRB 060930: near-IR afterglow candidate
  7. GRB 061002: Swift-XRT Team Refined Analysis
  8. VLA observations of GRB 060926
  9. GRB061002 - SDSS Pre-Burst Observations
  10. GRB 061002, Swift-BAT refined analysis
  11. GRB 060908: Detection of a possible host
  12. GRB 060807: Detection of a possible host galaxy
  13. GRB 060923A: VLA K-band Observations
  14. GRB 060930: Xinglong TNT optical observations
  15. GRB 060929: Further XRT Refined Analysis
  16. GRB 060929: Swift/UVOT Optical Observations
  17. GRB 060930: A long X-ray rich GRB detected by INTEGRAL
  18. GRB060929: Swift-XRT refined analysis.
  19. GRB 060929: TNG K-band observations
  20. GRB 060929, Swift-BAT refined analysis
  21. GRB060929: Optical limit
  22. Liverpool Telescope observations of GRB 060929
  23. GRB060908: optical observations
  24. GRB 060927: Swift/UVOT Optical Observations
  25. GRB 060927: Swift XRT Team refined analysis
  26. GRB 060927 optical limit
  27. GRB 060927, Swift-BAT refined analysis
  28. GRB 060927: Xinglong TNT optical observations
  29. GRB 060927, optical observation
  30. GRB060927 - SDSS Pre-Burst Observations
  31. Swift XRT boresight
  32. GRB060926: VLT redshift
  33. GRB 060926: Swift-UVOT Detections
  34. GRB 060923A: Schedule of Spitzer Space Telescope Observations
  35. GRB 060926, Swift-BAT refined analysis
  36. GRB 060923A: Radio Observations
  37. GRB 060926: RTT150, UVOT afterglow candidate confirmation
  38. GRB 060926: Swift detection of a burst
  39. GRB 060923C, Swift-BAT refined analysis
  40. GRB 060923C: VLA Observation
  41. GRB 060923C: NIR afterglow confirmed
  42. GRB060923C: AROMA optical obsevation
  43. GRB 060923C, optical observation
  44. GRB 060923A: Gemini Second Epoch and Afterglow Confirmation
  45. GRB 060923C: VLT J-band observations
  46. GRB 060923B: Swift XRT Refined Analysis
  47. GRB 060923A: Swift XRT refined analysis
  48. GRB 060923A: Keck and Gemini Observations
  49. GRB 060923C: Xinglong TNT optical observations
  50. GRB 060923B, Swift-BAT refined analysis
  51. GRB 060923C: Swift detection of a burst
  52. GRB 060923B: Swift detection of a burst
  53. GRB 060923, Swift-BAT refined analysis
  54. GRB 060923: UKIRT nIR observations - candidate afterglow
  55. GRB060923 - SDSS Pre-Burst Observations
  56. GRB 060923: Swift detection of a burst
  57. Swift detects a hard X-ray burst from AXP CXOU J164710.2-455216
  58. GRB 060919 : Faulkes South Telescope Observations
  59. GRB 060919, Swift-BAT refined analysis
  60. GRB060919: XRT refined analysis
  61. GRB 060919: TAROT optical observations
  62. GRB 060919: Swift detection of a burst
  63. GRB 060912A: VLA Observation
  64. GRB 060912A: Probable Host Galaxy
  65. GRB 060912, Swift-BAT refined analysis
  66. GRB 060912: Correction to GCN 5559
  67. GRB 060912: Swift detection of a burst with an optical afterglow
  68. VLA observations of GRB 060908
  69. GRB 060908, Swift-BAT refined analysis
  70. GRB 060908 - SDSS Pre-burst Observations
  71. GRB 060908: REM optical prompt observation
  72. GRB 060908: Swift detection of a burst with a bright optical counterpart
  73. GRB 060904A: Suzaku/WAM observation of the prompt emission
  74. GRB060906 , optical observation
  75. GRB 060906: Early RAPTOR optical limits
  76. GRB 060906, Swift-BAT refined spectral analysis
  77. GRB 060906: Swift/XRT Refined Analysis
  78. VLT redshift of GRB 060906
  79. GRB 060906, Swift-BAT refined analysis
  80. GRB 060906: Confirmation of P60 Optical Afterglow
  81. GRB 060906 (?): P60 Optical Afterglow Candidate
  82. GRB060904b, optical observations
  83. GRB060904A: Swift/UVOT optical observations
  84. GRB 060904A: Subaru NIR observation
  85. GRB 060904B: Swift-BAT refined analysis
  86. GRB 060904A: Refined analysis of the Swift-BAT burst
  87. GRB 060904A: Suzaku-XIS and -HXD observation plan
  88. GRB 060904A: P60 Observations
  89. GRB 060904B: Optical observations at Crni Vrh
  90. GRB 060904B: TAROT optical counterpart observations
  91. GRB060904B - SDSS Pre-Burst Observations
  92. GRB 060904: TAROT optical observations
  93. GRB 060904B: Swift detection of a burst with optical counterpart
  94. GRB060904 - SDSS Pre-Burst Observations
  95. GRB 060904: Swift detection of a bright burst
  96. GRB060901: Optical observations
  97. 060901: Swift UVOT followup observations
  98. GRB 060901: Swift/XRT Refined Analysis
  99. GRB 060901: Swift/XRT Position
  100. GRB 060901: a long GRB detected by INTEGRAL

Advanced

Download all Circulars as a .tar.gz archive (updated once a day):
Looking for U.S. government information and services? Visit USA.gov