Skip to main content
Circulars over Kafka event name backfill. 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').

18348 results found.

  1. GRB 060213: IPN localization
  2. GRB 060211a: WIRO NIR Observations
  3. GRB 060211B: BAT detects no additional burst emission beyond T + 122 sec
  4. GRB 060211A: Further refined analysis of the Swift burst
  5. GRB 060210: ARC NIR Detection of Afterglow and Possible Host Galaxy
  6. GRB 060211A: Partial refined analysis on the Swift-BAT burst
  7. GRB 050826: Optical Afterglow and Host Galaxy
  8. GRB 060210: Further refined analysis of the Swift-BAT burst
  9. GRB 060211B: Swift/BAT refined analysis
  10. GRB060210: Swift/UVOT Upper Limits
  11. GRB 060211B: Swift-XRT Team refined analysis
  12. GRB060211B: Swift/XRT position
  13. GRB 060210: Optical Observations
  14. GRB 060211A: Swift XRT Team Refined Analysis
  15. GRB 060211B: Swift-BAT detection of a burst
  16. GRB060211: Faulkes North observation
  17. GRB 060211: Swift detection of a long burst
  18. GRB 060210: Refined analysis of the Swift-BAT burst
  19. GRB060210: Swift XRT Refined Analysis
  20. GRB060210: Early Optical Observations
  21. GRB060210:Faulkes Telescope North Afterglow Confirmation
  22. GRB 060210: candidate afterglow
  23. GRB 060210: Swift detection of a burst
  24. GRB060210: Optical afterglow
  25. GRB 060206: Swift/UVOT Observations
  26. Swift-BAT trigger 180931 is not a GRB
  27. GRB060209: RTT150 optical observations
  28. GRB 060209 : TAROT optical observation
  29. GRB 060209(?): Swift-BAT detection of a possible burst
  30. GRB 060206: WSRT Radio Observations
  31. GRB 060203: Swift/UVOT upper limits
  32. GRB060204a: Swift XRT Source is not GRB Afterglow
  33. GRB 060204b: pseudo-z from spectral parameters of the prompt emission
  34. GRB 060204A: ROSAT Pointing
  35. GRB060204A: Swift/UVOT observations
  36. GRB 060206: Swift-BAT refined analysis
  37. GRB060206: Swift XRT Refined Analysis
  38. GRB060206: Swift XRT Position
  39. GRB060204a: Swift XRT Detection of an Afterglow Candidate
  40. GRB060206 - Swift UVOT Confirmation of Optical Afterglow
  41. GRB060206: Swift-BAT detection of a burst
  42. GRB 060204C: XRT analysis of Swift J061223.0+701243.9
  43. BAT GRB 060204C is probably not a GRB
  44. GRB 060204B: BVRi-band detections of optical afterglow
  45. GRB 060204A: Swift XRT upper limit
  46. GRB060204B: Swift/UVOT refined analysis
  47. Swift XRT Observation of GRB 060204C
  48. GRB 060204B: Swift-BAT refined analysis
  49. GRB060204B: Swift XRT Team Refined Analysis
  50. GRB 060204C: OSN limits
  51. GRB 060204C: Liverpool Telescopes optical limit
  52. GRB 060204C: ROTSE-III Optical Limits
  53. GRB 060204C: Swift-BAT detection of a burst
  54. GRB 060124: Radio Observations
  55. GRB060204B: Faulkes OT candidate
  56. GRB060204B, optical observation
  57. GRB060204B - SDSS pre-burst observations
  58. GRB 060203: Swift-BAT refined analysis
  59. GRB 060204B: Swift detection of a burst
  60. GRB 060203: RTT150 optical observations
  61. GRB060203: Swift XRT Team Refined Analysis
  62. GRB060203 - Swift UVOT observation
  63. Swift-BAT trigger is GRB 060203
  64. GRB060203: Observations with SARA
  65. GRB 060203: P60 Confirmation of Optical Afterglow
  66. Possible GRB 060203: candidate optical counterpart
  67. Swift BAT Trigger 180151: Swift XRT source detection
  68. Possible GRB 060203: optical observations at Asiago
  69. Swift-BAT trigger 180151 is unknown origin at this time
  70. GRB 060202: Refined analysis of the Swift-BAT burst
  71. GRB060202, optical observation
  72. GRB 060202: Swift/UVOT upper limits
  73. GRB 060202: Swift XRT Team Refined Analysis
  74. GRB060202: Faulkes North observation
  75. GRB 060202: Swift detection of a burst
  76. GRB 060130: Swift/XRT observation
  77. GRB 060123: VLA Radio Observations
  78. Possible GRB 051221B: MDM Correction
  79. GRB 060123: Swift refined analysis of an unusual GRB
  80. GRB060124, BVRcIc field calibration
  81. GRB060105: refined analysis of the Suzaku observation
  82. GRB 060124: HETE detection and spectrum of the main peak
  83. Konus-Wind observation of GRB 060124
  84. GRB060124: detailed XRT analysis
  85. GRB 060124 Optical Observations
  86. GRB 060124: R band Observations
  87. GRB 060124: Extremely long burst, Swift-BAT refined analysis
  88. GRB 060123: Swift detection of a very long, faint burst
  89. GRB 060124: TAROT optical limits
  90. GRB 060124: Swift/UVOT Observation
  91. GRB 060124: Confirmation of the Afterglow
  92. GRB 060124: XRT position
  93. GRB 060124: Optical Observations at Tautenburg
  94. GRB 060117: Suzaku WAM observation of the prompt emission
  95. GRB060124:MASTER optical observation
  96. GRB 060111B: Suzaku WAM observation of the prompt emission
  97. GRB 060124: Swift-BAT detection of a burst
  98. GRB 060116: Radio Detection
  99. GRB 060116: MARGE optical observations
  100. GRB 060121: Swift/UVOT upper limits

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