Skip to main content
New! Super-Kamiokande JSON Notices and Schema v4.5.0. 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"

26361 results found.

  1. GRB 050724: WHT optical observations
  2. GRB050713: analysis of the XMM-Newton observation
  3. Swift-BAT trigger 147918 is not a real GRB
  4. GRB050724: VLT observations of the variable source
  5. GRB050709: Second Epoch Chandra Observation
  6. GRB050726: Swift-BAT detection of a weak burst
  7. GRB 050724: Optical Variability in Nearby Galaxy
  8. GRB 050724: J-band observations
  9. GRB 050724: GMOS Imaging and Spectroscopy
  10. GRB050724: Radio Observation
  11. GRB 050724: Optical imaging/astrometry
  12. GRB 050724: Swift/UVOT Upper Limit
  13. GRB050724: Refined analysis of the Swift-BAT possible short burst
  14. GRB 050724: possible host galaxy in DSS
  15. GRB 050721A: Swift-BAT refined analysis
  16. GRB 050721A: Early Swift XRT analysis results
  17. GRB050721A: optical decay
  18. GRB 050721: optical afterglow confirmed
  19. GRB 050709: Refined Spectral and Temporal Properties
  20. GRB050714b: Radio Observation
  21. GRB050712: Radio Observations
  22. GRB050713a: Radio Observation
  23. GRB 050712, Tautenburg optical afterglow observations
  24. Swift-BAT detection of a possible GRB
  25. GRB 050714B: VLT R-band observations
  26. GRB 050717: Additional LCO observations
  27. GRB 050716; J-band observations
  28. GRB 050717: LCO near-IR observations
  29. Swift/UVOT Observations of GRB 050717
  30. GRB 050717: Swift-BAT refined analysis
  31. GRB050717: Swift XRT position
  32. Swift detection of GRB 050717
  33. Swift UVOT Observations of GRB 050716
  34. GRB 050716: Refined XRT analysis.
  35. GRB050716: Refined analysis of the Swift-BAT burst
  36. GRB 050716: Lulin B and R band optical observations
  37. GRB050716, optical observation
  38. GRB050716: Faulkes North Telescope observation
  39. GRB050715: Refined analysis of the Swift-BAT burst
  40. GRB 050715: Swift-BAT detection
  41. GRB 050713b: RTT150 optical observations
  42. GRB050714B: Refined analysis of the Swift-BAT burst
  43. GRB 050714B: optical afterglow
  44. GRB 050714, R-band candidate
  45. GRB 050714, optical observations
  46. GRB 050713A: XRT refined analysis
  47. GRB 050713A: RAPTOR detection of early optical emission
  48. GRB050713B :Swift/UVOT observations
  49. GRB050713b: XRT refined analysis
  50. GRB050712: TNG R-band observations
  51. GRB 050713B: Swift-BAT Refined Analysis
  52. GRB 050713A: Swift/UVOT observation
  53. GRB 050713A : Swift-BAT Refined Analysis
  54. GRB050712: Swift UVOT Observation of Afterglow Emission
  55. GRB 050713A : Lulin R-band observation
  56. GRB 050713A XMM-Newton observation
  57. GRB 050713b : Lulin R-band observations
  58. GRB050713B: Faulkes North Telescope observation
  59. RBO RI observations of GRB 050713A
  60. GRB 050713B
  61. GRB050709 : Chandra source optical counterpart
  62. GRB050713: Liverpool Telescope prompt observations
  63. GRB 050712, optical observations
  64. GRB050709: Candidate X-ray Afterglow from Chandra
  65. GRB050713: possible I-band afterglow
  66. GRB050712: XRT refined analysis
  67. GRB050709: Radio Observations
  68. GRB 050709: Swift UVOT and XRT observations
  69. GRB 050712: Swift-BAT Refined Analysis
  70. GRB050712: UVOT candidate optical counterpart
  71. GRB 050709: LCO40 Observations
  72. GRB050709, optical observations
  73. PROMPT Rc Observations of GRB 050709
  74. GRB 050525a: PROMPT VRcIc Detections
  75. GRB 050525a: ARC 3.5-meter Optical and NIR Observations
  76. GRB 050525a: ARC 3.5-Meter SPIcam Field Calibration
  77. GRB 050626: Swift XRT observations
  78. GRB 050408: ARC 3.5-meter NIR Observations
  79. GRB 050701: Refined XRT analysis
  80. Swift UVOT observations of GRB 050701
  81. GRB050701: Swift-BAT Refined analysis
  82. Swift trigger 143708 is really GRB 050701
  83. GRB 050607, radio observations
  84. H11603: An X-ray flare from V4641 Sgr, or a possible XRF
  85. GRB050525a: HST Observations
  86. H3800 and H3801 on 2005 June 11: two bursts from SGR1806-20 localized by HETE
  87. XRF 050509c: Optical monitoring
  88. Konus-Wind observation of an intermediate burst from SGR 1806-20
  89. XRF050509c: Radio Detection
  90. GRB 050607 optical decay
  91. GRB050607: refined analysis of prompt REM observations
  92. GRB 050607: PROMPT VRcIc Observations
  93. GRB 050607: Optical decay and spectral slope
  94. GRB050607,optical observation
  95. Optical Afterglow of GRB 050607
  96. GRB050607: Swift Detection of a long GRB
  97. GRB050607: prompt REM observations
  98. Limits on a SN in the field of GRB 050509b
  99. GRB 050603 - XRT data analysis of the first day
  100. GRB050603, submillimetre 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