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"

15252 results found.

  1. GRB 051022 Chandra Observations scheduled
  2. GRB051021a: optical observations
  3. GRB051021A: Swift XRT refined analysis
  4. Konus-Wind observation of GRB 051022
  5. GRB051022: Optical Observations
  6. GRB 051022: Spectral Analysis Indicates That The Spectrum Is Absorbed
  7. GRB 051021, SMARTS optical/IR observations
  8. GRB 051021: P200 Ks Observations
  9. GRB 051021: MDM Upper Limit
  10. GRB 051022 (=H3950): SXC Flight Localization is Valid
  11. GRB 051021,optical observation
  12. GRB051021B: Swift XRT Position
  13. GRB 051021B: Swift detection of a burst
  14. GRB051021: Swift XRT analysis
  15. GRB 051021 : optical afterglow observation at Lulin
  16. GRB 051021: Optical observations
  17. GRB051021: A GRB Localized by HETE
  18. Afterglow candidate of GRB 051016B observed at Lulin
  19. GRB 051016b: Gemini Near IR Observations
  20. GRB 051016B: refined analysis of the Swift/XRT data
  21. GRB 051016B: Swift/UVOT detection
  22. GRB051016: Swift XRT refined analysis.
  23. GRB 051016: PROMPT Observations
  24. Photometric calibration of Swift/UVOT and Re-analysis of Swift/UVOT GRB 050922C data
  25. Swift-BAT Trigger 159578 is a possible burst
  26. GRB051008: optical candidate
  27. GRB 051008: - a high redshift high-luminosity burst?
  28. GRB 051008 - a low redshift low-luminosity burst?
  29. GRB051008: Swift XRT refined analysis
  30. Konus-Wind observation of GRB 051008
  31. GRB 051008: R-band upper limit
  32. GRB 051008: Swift XRT position
  33. GRB 051008, optical observations
  34. GRB 051006: XRT refined analysis
  35. GRB 051006: XRT position
  36. GRB051006: Swift detection of a burst
  37. GRB 050906, summary of radio observations
  38. GRB 050925: Second Epoch WSRT Radio Observations
  39. GRB 051001: Swift XRT refined analysis
  40. GRB 051001, optical observations at Mt. John
  41. GRB 051001: Swift-BAT refined analysis
  42. GRB 050922C: further VLT observations
  43. GRB 050820A: NIR photometry at the TNG
  44. GRB050922C: UVES/VLT high resolution spectroscopy
  45. GRB/SGR 050925: IR Observations
  46. GRB050925: Swift UVOT upper limits
  47. GRB050925: Faulkes Telescope North R-band limit
  48. GRB 050922B: Correction to BAT refined analysis, longer burst
  49. GRB050922B: refined XRT analysis
  50. Konus-Wind observation of GRB 050922C
  51. GRB OT observation
  52. GRB050922C: observation at MonteBoo
  53. GRB050922C: Optical Observations
  54. GRB 050922C: Swift XRT refined analysis
  55. HETE Fregate observations of GRB 050922C
  56. GRB 050922C: Swift detection of a bright burst
  57. GRB 050922C: ROTSE-IIId Refined Analysis
  58. GRB050922B: Swift-BAT detection of a weak long burst
  59. GRB050820B: analysis of the XMM-Newton observation
  60. GRB050916: Swift/UVOT Upper Limits
  61. GRB 050916: Swift-BAT refined analysis
  62. GRB 050915a: Radio Observations
  63. Swift-BAT trigger 155535 is definitely not a GRB
  64. GRB 050916: XRT position
  65. GRB 050915b, SMARTS optical/IR observations of the XRT position
  66. GRB050916: Swift-BAT detection of a long weak burst
  67. GRB 050915a: IR Transient
  68. GRB 050915B: XRT position
  69. GRB 050915: Swift XRT refined analysis
  70. GRB 050915: Swift-BAT refined analysis
  71. GRB050915, optical observations
  72. GRB050915: XRT position
  73. Swift-BAT trigger 155072 ground analysis
  74. GRB 050908: DEIMOS spectrum and further analysis
  75. GRB050911: Swift-XRT position
  76. GRB050908: detection of Swift/UVOT optical counterpart
  77. RBO GRB 050908 observations
  78. WIRO observations in I of GRB 050908
  79. GRB050908 : Swift-XRT refined analysis
  80. GRB 050908: Swift-BAT refined analysis
  81. GRB 050908: Optical observations
  82. Gemini Spectroscopy of GRB 050908
  83. GRB 050908 : Swift XRT position
  84. GRB 050908: KAIT observations
  85. GRB 050904 BAT refined analysis of complete data set
  86. GRB 050904: Subaru Optical Spectroscopy
  87. GRB 050906: Swift-BAT refined analysis
  88. GRB 050906: Swift XRT upper limit
  89. GRB 050904: Keck I-band Imaging
  90. GRB 050904: BOOTES early R-band observation
  91. GRB 050904: Did SWIFT/XRT see the prompt GRB emission ?
  92. GRB 050906: Swift/BAT Detection of a possible burst
  93. GRB 050904: Swift/UVOT observations
  94. GRB 050904: BAT refined analysis of partial data set
  95. GRB 050904: TAROT optical measurements
  96. GRB050904: Optical Observations
  97. GRB 050904: Environmental Constraints
  98. GRB 050904: Possible High-Redshift GRB
  99. GRB 050904: SOAR/PROMPT Observations
  100. GRB050904: Swift-BAT detection of a probable burst

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