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').

18347 results found.

  1. GRB 050822: Swift detection of a long burst
  2. Correction to Eiso calculation in GCN 3835 on GRB 050820A
  3. GRB050825a - very long GRB like GRB041219a? (Konus-Wind observation)
  4. GRB050820a BVRcIc field photometry
  5. GRB050820B XMM-Newton observation
  6. GRB 050820a: NIR Observations by WIRO
  7. GRB 050820B: Swift XRT position
  8. GRB050820B: Refined analysis of the Swift-BAT burst
  9. GRB050820B: BAT-Swift detection of a bright GRB
  10. Swift/UVOT photometry of GRB050820
  11. GRB050820: refined XRT analysis
  12. GRB 050820: Early RAPTOR detections
  13. GRB 050820 Swift-BAT refined analysis
  14. GRB050819: refined XRT analysis
  15. GRB 050820: Swift detection of a GRB
  16. GRB050820: Optical afterglow from P60
  17. GRB 050819 Swift-BAT refined analysis
  18. GRB050819: Swift XRT position
  19. GRB050819: Swift-BAT detection of a weak burst
  20. Swift-BAT trigger 150993 is not a GRB
  21. Swift Trigger 150823 is HETE J1900.1-2455
  22. GRB050817: Swift-BAT Detection of a burst
  23. GRB050815: Optical afterglow detection by Swift UVOT
  24. GRB050815: XRT refined analysis
  25. GRB050815: Refined analysis of the Swift-BAT burst
  26. GRB 050815: ROTSE-III Optical Limits
  27. GRB050815: Swift XRT afterglow localization
  28. GRB050815: Swift-BAT detection of a burst
  29. GRB050814: P60 Optical Afterglow Candidate
  30. GRB 050814: XRT refined analysis
  31. GRB050814: SWIFT/UVOT observation
  32. GRB050814: Refined analysis of the Swift-BAT burst
  33. GRB 050814: Swift XRT Afterglow Localization
  34. GRB 050814: Swift detection of a burst
  35. GRB050813, SDSS pre-burst observations
  36. GRB 050813: KAIT optical limit
  37. GRB 050813: Swift-BAT refined analysis
  38. GRB050813: SWIFT/UVOT observation
  39. GRB 050813: Swift XRT afterglow localization
  40. GRB 050813: Possible Short Swift-BAT GRB
  41. GRB050813 (Swift 150139): P60 Observations
  42. Swift-BAT trigger 150131 is not a GRB
  43. GRB050805b: CrAO optical limit
  44. GRB050805a : Null detection report
  45. Swift-BAT trigger 149118 is very likely not a GRB
  46. Retraction of Swift Trigger 149131 (GRB 050805B)
  47. GRB 050805b: OHP optical limits
  48. GRB 050805b: TAROT optical limits
  49. GRB050805b: MASTER optical observations
  50. Possible GRB 050805B: Swift-BAT trigger 149131 may be a burst
  51. GRB050805a: MASTER optical candidat
  52. Swift-BAT trigger 149118 is probably not a GRB
  53. GRB050803: Optical/UV Upper Limits from Swift-UVOT
  54. GRB 050803: Swift-BAT refined analysis
  55. GRB050803: MASTER further analys
  56. GRB 050803: early Swift XRT analysis results
  57. GRB 050803: TAROT optical limits
  58. GRB050803: MASTER optical observations
  59. GRB050803: Swift-BAT detection of a very long burst
  60. GCN GRB observation 050713A
  61. GRB 050802: Swift/UVOT optical and UV detections
  62. GRB050802 radio non-detection
  63. GRB 050730: OHP optical observations
  64. GRB 050802: early Swift XRT analysis results
  65. GRB 050802: Swift/UVOT observations
  66. GRB 050802: Swift-BAT refined analysis
  67. GRB 050802: XRT position
  68. GRB 050802: Swift Gamma-ray Burst
  69. GRB050801: Swift/UVOT Optical and UV detections
  70. GCN 050801: early Swift XRT analysis results
  71. GRB 050801: Swift-BAT refined analysis
  72. GRB 050801, afterglow observations
  73. GRB 050730, corrected photometry and break?
  74. GRB 050801: ROTSE-III Early Afterglow Break
  75. GRB050801: Swift-BAT detection of a burst
  76. GRB050801: GCN XRT position is incorrect
  77. GRB 050801: ROTSE-III Detection of Possible Counterpart
  78. GRB 050730: XRT refined analysis
  79. GRB 050730: early TAROT optical observations
  80. Swift/UVOT photometry of GRB050730
  81. GRB050730: Refined BAT analysis of the Swift-BAT burst
  82. GRB 050730: Swift XRT afterglow observations
  83. GRB 050730 XMM-Newton observation
  84. GRB050730, afterglow observations
  85. GRB 050730: Redshift Measurement based on Magellan/MIKE Observations
  86. GRB050730: Liverpool Telescope optical observations
  87. GRB 050730, optical candidate
  88. GRB050730: Swift-BAT detection of a weak burst
  89. GRB 050713A: Swift XRT extended light curve
  90. GRB050726: Swift UVOT observations
  91. GRB 050724: Chandra Observations of the X-ray Afterglow
  92. GRB050713: analysis of the XMM-Newton observation
  93. Swift-BAT trigger 147918 is not a real GRB
  94. GRB 050727: RTT150 optical observations
  95. GRB050727: KAIT optical limit
  96. GRB 050724: dust-scattered X-ray halo detected in SWIFT/XRT observation
  97. GRB 050726: early Swift XRT analysis results
  98. GRB050726: Swift-BAT detection of a weak burst
  99. GRB 050724: SWIFT XRT refined position
  100. GRB 050724: optical and near-IR observations

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