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"

28047 results found.

  1. GRB 050721A: Swift-BAT refined analysis
  2. GRB 050721A: Early Swift XRT analysis results
  3. GRB050721A: optical decay
  4. GRB 050721: optical afterglow confirmed
  5. GRB 050709: Refined Spectral and Temporal Properties
  6. GRB050714b: Radio Observation
  7. GRB050712: Radio Observations
  8. GRB050713a: Radio Observation
  9. GRB 050712, Tautenburg optical afterglow observations
  10. Swift-BAT detection of a possible GRB
  11. GRB 050714B: VLT R-band observations
  12. GRB 050717: Additional LCO observations
  13. GRB 050716; J-band observations
  14. GRB 050717: LCO near-IR observations
  15. Swift/UVOT Observations of GRB 050717
  16. GRB 050717: Swift-BAT refined analysis
  17. GRB050717: Swift XRT position
  18. Swift detection of GRB 050717
  19. Swift UVOT Observations of GRB 050716
  20. GRB 050716: Refined XRT analysis.
  21. GRB050716: Refined analysis of the Swift-BAT burst
  22. GRB 050716: Lulin B and R band optical observations
  23. GRB050716, optical observation
  24. GRB050716: Faulkes North Telescope observation
  25. GRB050715: Refined analysis of the Swift-BAT burst
  26. GRB 050715: Swift-BAT detection
  27. GRB 050713b: RTT150 optical observations
  28. GRB050714B: Refined analysis of the Swift-BAT burst
  29. GRB 050714B: optical afterglow
  30. GRB 050714, R-band candidate
  31. GRB 050714, optical observations
  32. GRB 050713A: XRT refined analysis
  33. GRB 050713A: RAPTOR detection of early optical emission
  34. GRB050713B :Swift/UVOT observations
  35. GRB050713b: XRT refined analysis
  36. GRB050712: TNG R-band observations
  37. GRB 050713B: Swift-BAT Refined Analysis
  38. GRB 050713A: Swift/UVOT observation
  39. GRB 050713A : Swift-BAT Refined Analysis
  40. GRB050712: Swift UVOT Observation of Afterglow Emission
  41. GRB 050713A : Lulin R-band observation
  42. GRB 050713A XMM-Newton observation
  43. GRB 050713b : Lulin R-band observations
  44. GRB050713B: Faulkes North Telescope observation
  45. RBO RI observations of GRB 050713A
  46. GRB 050713B
  47. GRB050709 : Chandra source optical counterpart
  48. GRB050713: Liverpool Telescope prompt observations
  49. GRB 050712, optical observations
  50. GRB050709: Candidate X-ray Afterglow from Chandra
  51. GRB050713: possible I-band afterglow
  52. GRB050712: XRT refined analysis
  53. GRB050709: Radio Observations
  54. GRB 050709: Swift UVOT and XRT observations
  55. GRB 050712: Swift-BAT Refined Analysis
  56. GRB050712: UVOT candidate optical counterpart
  57. GRB 050709: LCO40 Observations
  58. GRB050709, optical observations
  59. PROMPT Rc Observations of GRB 050709
  60. GRB 050525a: PROMPT VRcIc Detections
  61. GRB 050525a: ARC 3.5-meter Optical and NIR Observations
  62. GRB 050525a: ARC 3.5-Meter SPIcam Field Calibration
  63. GRB 050626: Swift XRT observations
  64. GRB 050408: ARC 3.5-meter NIR Observations
  65. GRB 050701: Refined XRT analysis
  66. Swift UVOT observations of GRB 050701
  67. GRB050701: Swift-BAT Refined analysis
  68. Swift trigger 143708 is really GRB 050701
  69. GRB 050607, radio observations
  70. H11603: An X-ray flare from V4641 Sgr, or a possible XRF
  71. GRB050525a: HST Observations
  72. H3800 and H3801 on 2005 June 11: two bursts from SGR1806-20 localized by HETE
  73. XRF 050509c: Optical monitoring
  74. Konus-Wind observation of an intermediate burst from SGR 1806-20
  75. XRF050509c: Radio Detection
  76. GRB 050607 optical decay
  77. GRB050607: refined analysis of prompt REM observations
  78. GRB 050607: PROMPT VRcIc Observations
  79. GRB 050607: Optical decay and spectral slope
  80. GRB050607,optical observation
  81. Optical Afterglow of GRB 050607
  82. GRB050607: Swift Detection of a long GRB
  83. GRB050607: prompt REM observations
  84. Limits on a SN in the field of GRB 050509b
  85. GRB 050603 - XRT data analysis of the first day
  86. GRB050603, submillimetre observations
  87. GRB050603: Radio Detection
  88. GRB 050603: Swift-BAT refined analysis of a long three-spiked burst
  89. GRB 050603: INTEGRAL shows it is not a short GRB
  90. GRB 050525a, infrared observations
  91. GRB050528, XRT observations
  92. GRB050528: updated Liverpool Telescope limits
  93. Swift-BAT GRB 050528: a soft burst
  94. GRB050504: Ashra-P2/3 monitor and Ashra-AFT response
  95. Possible GRB050528: no candidate from Liverpool Telescope
  96. GRB050525a: Radio Observations
  97. GRB 050509b: refined XRT/Chandra afterglow position analysis
  98. GRB 050525: RTT150, Optical observations
  99. GRB 050525a: SARA Observations
  100. GRB 050525B: Swift-BAT observations

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