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"

28089 results found.

  1. GRB050801: Radio Observation
  2. GRB050730: Radio Detection
  3. GRB 050803: Keck Observations
  4. GRB 050803: Swift-BAT refined analysis
  5. GRB 050802.422: Fading of the afterglow and detection of the host
  6. GRB 050803: early Swift XRT analysis results
  7. GRB 050803: TAROT optical limits
  8. GCN GRB observation 050713A
  9. GRB050730: FORS1 and UVES/VLT low- and high-resolution spectroscopy
  10. GRB050802 radio non-detection
  11. GRB 050730: OHP optical observations
  12. GRB 050802: early Swift XRT analysis results
  13. GRB 050802: Swift/UVOT observations
  14. GRB 050802: Swift-BAT refined analysis
  15. GRB050801: Optical photometry and decay index
  16. GRB 050802: Swift Gamma-ray Burst
  17. GRB050801: Swift/UVOT Optical and UV detections
  18. GRB 050730: Preliminary Analysis of MIKE Spectrum
  19. GCN 050801: early Swift XRT analysis results
  20. GRB 050801: Swift-BAT refined analysis
  21. GRB 050730: XRT refined analysis
  22. GRB 050730: early TAROT optical observations
  23. GRB 050730, spectra and optical photometry
  24. GRB050730: Refined BAT analysis of the Swift-BAT burst
  25. GRB 050730 XMM-Newton observation
  26. GRB050730: Swift-BAT detection of a weak burst
  27. GRB050713b: Maidanak optical observations
  28. GRB 050724: Secure Host Redshift from Keck
  29. GRB 050724: WHT optical observations
  30. GRB050713: analysis of the XMM-Newton observation
  31. Swift-BAT trigger 147918 is not a real GRB
  32. GRB050724: VLT observations of the variable source
  33. GRB050709: Second Epoch Chandra Observation
  34. GRB050726: Swift-BAT detection of a weak burst
  35. GRB 050724: Optical Variability in Nearby Galaxy
  36. GRB 050724: J-band observations
  37. GRB 050724: GMOS Imaging and Spectroscopy
  38. GRB050724: Radio Observation
  39. GRB 050724: Optical imaging/astrometry
  40. GRB 050724: Swift/UVOT Upper Limit
  41. GRB050724: Refined analysis of the Swift-BAT possible short burst
  42. GRB 050724: possible host galaxy in DSS
  43. GRB 050721A: Swift-BAT refined analysis
  44. GRB 050721A: Early Swift XRT analysis results
  45. GRB050721A: optical decay
  46. GRB 050721: optical afterglow confirmed
  47. GRB 050709: Refined Spectral and Temporal Properties
  48. GRB050714b: Radio Observation
  49. GRB050712: Radio Observations
  50. GRB050713a: Radio Observation
  51. GRB 050712, Tautenburg optical afterglow observations
  52. Swift-BAT detection of a possible GRB
  53. GRB 050714B: VLT R-band observations
  54. GRB 050717: Additional LCO observations
  55. GRB 050716; J-band observations
  56. GRB 050717: LCO near-IR observations
  57. Swift/UVOT Observations of GRB 050717
  58. GRB 050717: Swift-BAT refined analysis
  59. GRB050717: Swift XRT position
  60. Swift detection of GRB 050717
  61. Swift UVOT Observations of GRB 050716
  62. GRB 050716: Refined XRT analysis.
  63. GRB050716: Refined analysis of the Swift-BAT burst
  64. GRB 050716: Lulin B and R band optical observations
  65. GRB050716, optical observation
  66. GRB050716: Faulkes North Telescope observation
  67. GRB050715: Refined analysis of the Swift-BAT burst
  68. GRB 050715: Swift-BAT detection
  69. GRB 050713b: RTT150 optical observations
  70. GRB050714B: Refined analysis of the Swift-BAT burst
  71. GRB 050714B: optical afterglow
  72. GRB 050714, R-band candidate
  73. GRB 050714, optical observations
  74. GRB 050713A: XRT refined analysis
  75. GRB 050713A: RAPTOR detection of early optical emission
  76. GRB050713B :Swift/UVOT observations
  77. GRB050713b: XRT refined analysis
  78. GRB050712: TNG R-band observations
  79. GRB 050713B: Swift-BAT Refined Analysis
  80. GRB 050713A: Swift/UVOT observation
  81. GRB 050713A : Swift-BAT Refined Analysis
  82. GRB050712: Swift UVOT Observation of Afterglow Emission
  83. GRB 050713A : Lulin R-band observation
  84. GRB 050713A XMM-Newton observation
  85. GRB 050713b : Lulin R-band observations
  86. GRB050713B: Faulkes North Telescope observation
  87. RBO RI observations of GRB 050713A
  88. GRB 050713B
  89. GRB050709 : Chandra source optical counterpart
  90. GRB050713: Liverpool Telescope prompt observations
  91. GRB 050712, optical observations
  92. GRB050709: Candidate X-ray Afterglow from Chandra
  93. GRB050713: possible I-band afterglow
  94. GRB050712: XRT refined analysis
  95. GRB050709: Radio Observations
  96. GRB 050709: Swift UVOT and XRT observations
  97. GRB 050712: Swift-BAT Refined Analysis
  98. GRB050712: UVOT candidate optical counterpart
  99. GRB 050709: LCO40 Observations
  100. GRB050709, optical 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