Skip to main content
End of Swift Science Operations, CHIME Notices Unavailable During Upgrade. See news and announcements

GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. 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"

28262 results found.

  1. GRB 221027A: Fermi GBM Final Real-time Localization
  2. GRB 221009A: Further Gemini-South Infrared Observations
  3. GRB 221024A: GRANDMA observations
  4. IPN triangulation of GRB 221022C (short)
  5. GRB 221023A: AGILE/GRID analysis
  6. SGR 1935+2154: AstroSat CZTI Detections
  7. GRB 221025A: AstroSat CZTI detection
  8. GRB 221009A: SARA-RM 1m Optical Afterglow Detection
  9. GRB 221009A: spectroscopic confirmation of SN in LBT spectra
  10. Konus-Wind detection of GRB 221023A
  11. GRB 221024A: Swift/UVOT UV upper limits
  12. GRB 221022A: Swift-XRT observations
  13. GRB 221024A: Swift-XRT refined Analysis
  14. GRB 221022B: Detection by GRBAlpha
  15. GRB 221025A: Fermi-LAT detection
  16. IPN triangulation of GRB 221022B (long)
  17. GRB 221024A: GIT confirmation of the optical afterglow
  18. GRB 221024A: Enhanced Swift-XRT position
  19. GRB 221024A: D50 candidate afterglow
  20. GRB 221022B: AstroSat CZTI detection
  21. GRB 221022A: Fermi GBM detection
  22. GRB 221022A: Swift ToO observations
  23. GRB 221023A: Fermi-LAT detection
  24. GRB 221022B: Fermi GBM detection
  25. GRB 221009A: Determination of the black holes mass and spin
  26. GRB 221024A: Swift detection of a burst
  27. GRB 221023A: Fermi GBM Final Localization
  28. GRB 221023A: AGILE detection of a burst
  29. GRB 221022A: Swift/BAT-GUANO detection
  30. GRB 221022B: Swift/BAT-GUANO detection outside the coded FOV
  31. GRB 221022B: AGILE detection
  32. GRB 221009A: James Webb Space Telescope Observations
  33. GRB 221022B: Fermi GBM Final Real-time Localization
  34. GRB 221009A: optical observations, SN photometric evidence
  35. GRB 221021A: Swift/BAT-GUANO detection outside the coded FOV
  36. GRB 221022A: Fermi GBM Final Real-time Localization
  37. GRB 221020A: Detection by GRBAlpha
  38. SGR 1935+21542: VZLUSAT-2 and GRBAlpha joint detection
  39. GRB 221017A: CALET Gamma-Ray Burst Monitor detection
  40. GRB 221021A: Fermi GBM Final Real-time Localization
  41. GRB 221009A: 1.3m DFOT Optical Observations
  42. GRB221009A: LBT optical imaging
  43. GRB 221009A: Peak luminosity of the supernova vs. synchrotron afterglow
  44. GRB 221017A: Swift-XRT observations
  45. GRB 221020A: Fermi GBM Final Real-time Localization
  46. Improved IPN localization for GRB 221009A (BepiColombo-MGNS light curve)
  47. GRB 221009A: TNG NIR detection
  48. GRB 221009A: BOAO NIR detections
  49. GRB 221009A X-ray light-curve and the indication of TeV light-curve
  50. AGILE detection of a burst from SGR J1935+2154 reported by VZLUSAT-2
  51. GRB 221009A: Spectroscopic detection of emerging SN features
  52. GRB 221009A: Continued LDT Afterglow Monitoring
  53. GRB 221013B: Swift/BAT-GUANO detection
  54. SGR 1935+2154: Bursting activity detected by VZLUSAT-2
  55. AGILE detection of the 2022 October 17 burst from SGR J1935+2154 reported by Konus-Wind
  56. GRB 221009A: GRANDMA observations
  57. SGR 1935+2154: Detection by GRBAlpha
  58. Konus-Wind detection of a burst from SGR 1935+2154 on 2022 October 17
  59. GRB 221017A: Swift ToO observations
  60. AGILE detection of short X-ray flaring activity contemporary to SGR J1935+2154 reported bursts
  61. GRB 221009A: Second epoch of NuSTAR data
  62. IPN triangulation of GRB 221017A (long)
  63. GRB 221016A: Swift/UVOT Detection
  64. GRB 221016A: Swift-XRT refined Analysis
  65. Konus-Wind detection of GRB 221016A
  66. GRB 220926B: Detection by GRBAlpha
  67. GRB 221009A: A type I BdHN of exceptional energetics
  68. GRB 221016A: z-band upper limit, possible afterglow brightening
  69. GRB 221017A: MAXI/GSC detection
  70. GRB 221016A: Enhanced Swift-XRT position
  71. GRB 221016A: LCOGT Optical Afterglow Detection
  72. GRB 221016A: Swift detection of a burst
  73. GRB 221016A: Fermi GBM Final Real-time Localization
  74. GRB 221009A: Faulkes Telescope North continued optical afterglow follow-up
  75. Konus-Wind detection of a short burst coincident with a bright radio burst from SGR 1935+2154
  76. GRB 221009A: continued Assy optical afterglow observations, possible SN evidence
  77. GRB 221009A: LEIA X-ray Afterglow Detection
  78. GRB 221009A: VLT spectroscopic detection of the host galaxy
  79. GRB 221009A: ATCA detection
  80. GRB 221009A: Armchair Energetics
  81. GRB 221009A: ALMA and ACA detections
  82. GRB 221009A: Large Binocular Telescope Observatory optical afterglow detection
  83. GRB 221009A: Pan-STARRS optical photometry
  84. GRB 221009A: VLA detection
  85. MAXI/GSC refined analysis of the bright X-ray afterglow of GRB 221009A/Swift J1913.1+1946
  86. GRB 221009A: continued REM optical/NIR observations and evidence for an achromatic steepening in the afterglow light curve
  87. GRB 221009A: IXPE preliminary upper limits of X-ray polarization
  88. GRB 221009A: HEBS detection
  89. GRB 221009A: Gemini-South Infrared Afterglow Detection
  90. GRB221009A: Gemini-South Optical Afterglow Detection
  91. GRB 221009A: a 397.7 GeV photon observed by Fermi-LAT at 0.4 day after the GBM trigger
  92. GRB 221014A: Fermi GBM Final Real-time Localization
  93. GRB 221009A: Gamma-ray Detection by SIRI-2
  94. GRB221009A: Ionospheric disturbance observed in India
  95. GRB221009A: Detection as sudden ionospheric disturbances (SID)
  96. MAXI GRB 221006A: Redshifts of the possible host galaxies
  97. GRB 221009A: search for neutrinos with KM3NeT
  98. GRB 221009A: MeerKAT detection
  99. GRB 221009A: Lowell Discovery Telescope Afterglow Detection
  100. GRB 221006A: Swift-XRT afterglow detection

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