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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"

36402 results found.

  1. GRB 221028A: LCOGT Optical Upper Limits
  2. GRB 221027B: COATLI Upper Limits
  3. Swift GRB 221028A: Global MASTER-Net observations report
  4. GRB 221028A: BOOTES-4/MET optical upper limit
  5. LIGO-Virgo-KAGRA and GEO600 statement on GRB 221009A
  6. GRB 221028A: GIT optical upper limit
  7. GRB 221027B: Swift/UVOT Upper Limits
  8. GRB 221028A: Swift detection of a burst
  9. GRB 221027B: FRAM-ORM and Ondrejov SBT optical limits
  10. Konus-Wind detection of GRB 221017A
  11. Swift GRB 221027B: Global MASTER-Net observations report
  12. GRB 221027B: Swift-XRT refined Analysis
  13. GRB 221027B: BOOTES-1 optical upper limit
  14. GRB 221027B: Enhanced Swift-XRT position
  15. GRB 221027B: Swift detection of a burst
  16. GRB 221027A: Fermi GBM detection
  17. IPN triangulation of GRB 221025A (short)
  18. Konus-Wind detection of GRB 221022B
  19. GRB 221024A: Mondy optical observations
  20. GRB 221027A: Fermi-LAT detection
  21. GRB 221027A: Fermi GBM Final Real-time Localization
  22. GRB 221009A: Further Gemini-South Infrared Observations
  23. GRB 221024A: GRANDMA observations
  24. Fermi Gamma-ray Burst Monitor trigger 688431261/221025954 is not a GRB
  25. IPN triangulation of GRB 221022C (short)
  26. GRB 221023A: AGILE/GRID analysis
  27. GRB 221024A: Swift-BAT refined analysis
  28. GRB 221025A: AstroSat CZTI detection
  29. GRB 221009A: SARA-RM 1m Optical Afterglow Detection
  30. GRB 221025A: Fermi GBM Observation
  31. GRB 221009A: spectroscopic confirmation of SN in LBT spectra
  32. Konus-Wind detection of GRB 221023A
  33. GRB 221024A: Swift/UVOT UV upper limits
  34. GRB 221022A: Swift-XRT observations
  35. GRB 221024A: Swift-XRT refined Analysis
  36. GRB 221023A: Fermi GBM Observation
  37. GRB 221022B: Detection by GRBAlpha
  38. GRB 221025A: Fermi-LAT detection
  39. IPN triangulation of GRB 221022B (long)
  40. GRB 221024A: GIT confirmation of the optical afterglow
  41. GRB 221024A: Enhanced Swift-XRT position
  42. GRB 221024A: D50 candidate afterglow
  43. GRB 221022B: AstroSat CZTI detection
  44. GRB 221022A: Fermi GBM detection
  45. GRB 221022A: Swift ToO observations
  46. Fermi Gamma-ray Burst Monitor detections of SGR 1935+2154
  47. GRB 221023A: Fermi-LAT detection
  48. GRB 221022B: Fermi GBM detection
  49. GRB 221021A: Fermi GBM observation
  50. GRB 221009A: Determination of the black holes mass and spin
  51. GRB 221024A: Swift detection of a burst
  52. GRB 221023A: Fermi GBM Final Localization
  53. GRB 221023A: AGILE detection of a burst
  54. GRB 221022A: Swift/BAT-GUANO detection
  55. GRB 221022B: Swift/BAT-GUANO detection outside the coded FOV
  56. GRB 221022B: AGILE detection
  57. GRB 221009A: James Webb Space Telescope Observations
  58. GRB 221022B: Fermi GBM Final Real-time Localization
  59. GRB 221009A: Analysis of the initial episode using data of GBM/Fermi and SPI-ACS/INTEGRAL
  60. GRB 221009A: optical observations, SN photometric evidence
  61. GRB 221021A: Swift/BAT-GUANO detection outside the coded FOV
  62. GRB 221022A: Fermi GBM Final Real-time Localization
  63. GRB 221020A: Detection by GRBAlpha
  64. SGR 1935+21542: VZLUSAT-2 and GRBAlpha joint detection
  65. GRB 221017A: CALET Gamma-Ray Burst Monitor detection
  66. GRB 221021A: Fermi GBM Final Real-time Localization
  67. GRB 221009A: 1.3m DFOT Optical Observations
  68. Fermi GBM trigger 687320613 / 221013100 (GRB 221013B) is not a GRB
  69. GRB221009A: LBT optical imaging
  70. GRB 221009A: Peak luminosity of the supernova vs. synchrotron afterglow
  71. GRB 221017A: Swift-XRT observations
  72. GRB 221020A: Fermi GBM Final Real-time Localization
  73. Improved IPN localization for GRB 221009A (BepiColombo-MGNS light curve)
  74. GRB 221009A: TNG NIR detection
  75. GRB 221009A: BOAO NIR detections
  76. GRB 221009A X-ray light-curve and the indication of TeV light-curve
  77. GRB 221009A: Spectroscopic detection of emerging SN features
  78. GRB 221009A: Continued LDT Afterglow Monitoring
  79. GRB 221013B: Swift/BAT-GUANO detection
  80. SGR 1935+2154: Bursting activity detected by VZLUSAT-2
  81. GRB 221009A: GRANDMA observations
  82. The probability of observing GRB 221009A at z = 0.151
  83. GRB 221009A: Medicina Radio Telescope observations
  84. GRB 221017A: Swift ToO observations
  85. GRB 221009A: Second epoch of NuSTAR data
  86. IPN triangulation of GRB 221017A (long)
  87. GRB 221016A: Swift-BAT refined analysis
  88. GRB 221016A: Swift/UVOT Detection
  89. GRB 221016A: Swift-XRT refined Analysis
  90. Konus-Wind detection of GRB 221016A
  91. GRB 221016A: Fermi GBM observation
  92. GRB 220926B: Detection by GRBAlpha
  93. GRB 221009A: A type I BdHN of exceptional energetics
  94. GRB 221016A: z-band upper limit, possible afterglow brightening
  95. GRB 221017A: MAXI/GSC detection
  96. GRB 221016A: Enhanced Swift-XRT position
  97. GRB 221016A: LCOGT Optical Afterglow Detection
  98. GRB 221016A: Swift detection of a burst
  99. GRB 221016A: Fermi GBM Final Real-time Localization
  100. GRB 221009A: Faulkes Telescope North continued optical afterglow follow-up

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