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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').
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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.

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subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

20008 results found.

  1. GRB 221028A: HCT optical upper limit
  2. GRB 221028A: AGILE detection
  3. GRB 221028A: MITSuME Okayama optical upper limits
  4. Swift GRB 221028A: Global MASTER-Net observations report
  5. GRB 221028A: BOOTES-4/MET optical upper limit
  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. Swift GRB 221027B: Global MASTER-Net observations report
  11. GRB 221027B: Swift-XRT refined Analysis
  12. GRB 221027B: BOOTES-1 optical upper limit
  13. GRB 221027B: Enhanced Swift-XRT position
  14. GRB 221027B: Swift detection of a burst
  15. Konus-Wind detection of GRB 221022B
  16. GRB 221024A: Mondy optical observations
  17. GRB 221027A: Fermi-LAT detection
  18. GRB 221024A: GRANDMA observations
  19. IPN triangulation of GRB 221022C (short)
  20. SGR 1935+2154: AstroSat CZTI Detections
  21. GRB 221024A: Swift-BAT refined analysis
  22. GRB 221009A: SARA-RM 1m Optical Afterglow Detection
  23. GRB 221024A: Swift/UVOT UV upper limits
  24. GRB 221022A: Swift-XRT observations
  25. GRB 221024A: Swift-XRT refined Analysis
  26. GRB 221022B: Detection by GRBAlpha
  27. GRB 221025A: Fermi-LAT detection
  28. IPN triangulation of GRB 221022B (long)
  29. GRB 221024A: GIT confirmation of the optical afterglow
  30. GRB 221024A: Enhanced Swift-XRT position
  31. GRB 221024A: D50 candidate afterglow
  32. GRB 221022B: AstroSat CZTI detection
  33. GRB 221022A: Fermi GBM detection
  34. GRB 221022A: Swift ToO observations
  35. Fermi Gamma-ray Burst Monitor detections of SGR 1935+2154
  36. GRB 221023A: Fermi-LAT detection
  37. GRB 221022B: Fermi GBM detection
  38. GRB 221021A: Fermi GBM observation
  39. GRB 221009A: Determination of the black holes mass and spin
  40. GRB 221024A: Swift detection of a burst
  41. GRB 221022A: Swift/BAT-GUANO detection
  42. GRB 221022B: Swift/BAT-GUANO detection outside the coded FOV
  43. GRB 221009A: optical observations, SN photometric evidence
  44. GRB 221021A: Swift/BAT-GUANO detection outside the coded FOV
  45. SGR 1935+21542: VZLUSAT-2 and GRBAlpha joint detection
  46. GRB 221017A: Swift-XRT observations
  47. Improved IPN localization for GRB 221009A (BepiColombo-MGNS light curve)
  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 221013B: Swift/BAT-GUANO detection
  53. SGR 1935+2154: Bursting activity detected by VZLUSAT-2
  54. AGILE detection of the 2022 October 17 burst from SGR J1935+2154 reported by Konus-Wind
  55. GRB 221009A: GRANDMA observations
  56. SGR 1935+2154: Detection by GRBAlpha
  57. The probability of observing GRB 221009A at z = 0.151
  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. GRB 221016A: Swift-BAT refined analysis
  63. GRB 221016A: Swift/UVOT Detection
  64. GRB 221016A: Swift-XRT refined Analysis
  65. Konus-Wind detection of GRB 221016A
  66. GRB 221016A: Fermi GBM observation
  67. GRB 221009A: A type I BdHN of exceptional energetics
  68. GRB 221016A: Enhanced Swift-XRT position
  69. GRB 221016A: Swift detection of a burst
  70. Swift GRB221016.99: Global MASTER-Net observations report
  71. GRB 221009A: Faulkes Telescope North continued optical afterglow follow-up
  72. Konus-Wind detection of a short burst coincident with a bright radio burst from SGR 1935+2154
  73. GRB 221009A: continued Assy optical afterglow observations, possible SN evidence
  74. Konus-Wind observation of the recent SGR 1935+2154 activity
  75. GRB 221009A: LEIA X-ray Afterglow Detection
  76. GRB 221009A: ATCA radio spectrum
  77. Fermi Gamma-ray Burst Monitor detections of SGR 1935+2154
  78. GRB 221009A: Armchair Energetics
  79. GRB 221009A: Fermi LAT data rate effects due to extremely high flux
  80. GRB 221009A: Large Binocular Telescope Observatory optical afterglow detection
  81. GRB 221009A: Pan-STARRS optical photometry
  82. MAXI/GSC refined analysis of the bright X-ray afterglow of GRB 221009A/Swift J1913.1+1946
  83. GRB 221009A: continued REM optical/NIR observations and evidence for an achromatic steepening in the afterglow light curve
  84. GRB 221009A: HEBS detection
  85. GRB 221009A: Gamma-ray Detection by SIRI-2
  86. GRB221009A: Detection as sudden ionospheric disturbances (SID)
  87. GRB 221009A: search for neutrinos with KM3NeT
  88. GRB221009A: LCOGT Continued Observations - Optical Upper Limits
  89. Fermi Gamma-ray Burst Monitor continues to detect SGR 1935+2154
  90. GRB 221009A/Swift J1913.1+1946: low-frequency ASKAP observations
  91. GRB 221006A: Swift-XRT afterglow detection
  92. GRB 221009A: MITSuME Okayama optical observation
  93. GRB 221009A: Sayan observatory 1.6-m telescope observations
  94. Fermi-GBM Observations of High Bursting Activity from SGR J1935+2154
  95. GRB 221009A/Swift J1913.1+1946: SMA observations
  96. INTEGRAL shows increasing activity in SGR J1935+2154
  97. GRB 221009A/Swift J1913.1+1946: eMERLIN observations
  98. INTEGRAL detection of a burst from SGR J1935+2154
  99. GRB 221009A: NuSTAR Detection
  100. GRB 221009A: LCOGT Optical Afterglow Detection

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