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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.

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

28224 results found.

  1. GRB 240331A: AstroSat CZTI detection
  2. GRB 240329A: AstroSat CZTI detection
  3. GRB 240331A: Fermi GBM Final Real-time Localization
  4. GRB 240329A: GRBAlpha detection
  5. GRB 240329A: Fermi GBM Final Real-time Localization
  6. GRB 240328C: Glowbug gamma-ray detection
  7. GRB 240328B: Fermi GBM Final Real-time Localization
  8. GRB 240328A: Fermi GBM Final Real-time Localization
  9. IceCube-240327B - IceCube observation of a high-energy neutrino candidate track-like event
  10. IceCube-240327A - IceCube observation of a high-energy neutrino candidate track-like event
  11. X-ray transient EP 240315a: Second epoch Chandra observations
  12. X-ray transient EP240315a: e-MERLIN radio observations
  13. X-ray transient EP240315a: Ondrejov D50 optical limit
  14. GRB 240320A: Glowbug gamma-ray detection
  15. Konus-Wind detection of GRB 240315C (possible counterpart of EP240315a)
  16. GRB 240315C / X-ray transient EP240315a: Swift/BAT detection
  17. GRB 240318A: Swift/BAT-GUANO detection of a burst outside the coded FOV
  18. X-ray transient EP240315a: ATCA detection of radio counterpart
  19. GRB 240320A: Fermi GBM Final Real-time Localization
  20. GRB 240317B: Swift/BAT-GUANO Angular Error Correction
  21. X-ray transient EP 240315a: Chandra observations
  22. X-ray transient EP240315a: MeerKAT radio detection
  23. GRB 240318A: Glowbug gamma-ray detection
  24. GRB 240317C: Glowbug gamma-ray detection
  25. GRB 240318B: Glowbug gamma-ray detection
  26. X-ray transient EP240315a: PRIME near infrared detection
  27. X-ray transient EP240315a: 3.6 m TNG NIR detection
  28. X-ray transient EP240315a: EP-FXT detection of the X-ray afterglow
  29. GRB 240318A: Fermi GBM Final Real-time Localization
  30. GRB 240317B: Swift/BAT-GUANO arcminute localization of a burst
  31. GRB 240317A: AstroSat CZTI detection
  32. GRB 240315B: AstroSat CZTI detection
  33. X-ray transient EP240315a: Kitab observatory optical upper limitns
  34. GRB 240317B: Fermi GBM Final Real-time Localization
  35. GRB 240317A: Fermi GBM Final Real-time Localization
  36. X-ray transient EP240315a: Kinder follow-up observations for AT 2024eju with Lulin observatory
  37. X-ray transient EP240315a: GROND J-band detection
  38. X-ray transient EP240315a: VLT/X-shooter spectroscopic redshift of z = 4.859
  39. X-ray transient EP240315a: Nanshan/HMT optical upper limit
  40. AT2024eju: followup observations with Liverpool Telescope suggest a fading transient
  41. X-ray transient EP240315a: ATLAS detection of a possible optical counterpart AT2024eju
  42. Einstein Probe detected of a fast X-ray transient EP240315a
  43. GRID detection of GRB 240306A
  44. Changes to the Fermi-GBM Triggering Thresholds
  45. GRB 240315A: Fermi GBM Final Real-time Localization
  46. GRB 240314A: Fermi GBM Final Real-time Localization
  47. GRB240204A: VIRT optical upper limit
  48. GRB 240312A: Glowbug gamma-ray detection
  49. GRB 240312A: GECAM detection of a long burst
  50. GRB 240303C: VZLUSAT-2 detection
  51. GRB 240310A: MASTER OT J200702.72-263928.7 inside 3sigma
  52. GRB 240310B: Glowbug gamma-ray detection
  53. GRB 240310A: Fermi GBM Final Real-time Localization
  54. GRB 240309A: MAXI/GSC detection
  55. GRID detection of GRB 240229A (Updated Report)
  56. GRID detection of GRB 240229A
  57. GRB 240308A: Fermi GBM Final Localization
  58. IceCube-240307A - IceCube observation of a high-energy neutrino candidate track-like event
  59. GRB 240229A: Glowbug gamma-ray detection
  60. GRB 240227A (short): Glowbug gamma-ray detection
  61. GRB 240229A: GRBAlpha detection
  62. Konus-Wind detection of GRB 231118A
  63. GRB 240306A: AstroSat CZTI detection
  64. GRB 240306A: Swift/BAT-GUANO detection of a burst
  65. GRB 240305C: AstroSat CZTI detection of a short burst
  66. GRB 240306A: Fermi GBM Final Real-time Localization
  67. GRB 240305C: Fermi GBM Final Real-time Localization
  68. GRB 240305A: Swift/BAT-GUANO arcminute localization of a burst
  69. GRB 231028C: Glowbug gamma-ray confirmation of a prior burst
  70. GRB 240218A: ALMA detection
  71. GRB 240218A: Chandra Detection and Jet Break Confirmation
  72. GRB 240305B: Fermi GBM Final Localization
  73. Konus-Wind detection of GRB 240227A (short/hard)
  74. GRB 240303B: VZLUSAT-2 detection
  75. GRB 240229A: VZLUSAT-2 detection
  76. IPN triangulation of GRB 240229A
  77. GRB 240305A: Fermi GBM Final Real-time Localization
  78. Swift Trigger 1218701: Yes, we triggered on Swift J151857.0-572147 again
  79. Swift Trigger 1218696: Another trigger on Swift J151857.0-572147
  80. GRB240218A: ATCA observation of the radio counterpart
  81. Transient EPW20240219aa: Optical observations with LDT
  82. Konus-Wind detection of GRB 240303B
  83. Swift Trigger 1218645: Another detection of Swift J151857.0-572147
  84. IPN triangulation of GRB 240303B
  85. GRB 240303B: Fermi GBM Detection
  86. GRB 240225B: Swift-XRT afterglow detection
  87. Swift detection of Swift J151857.0-572147
  88. GRB 240303B: CALET Gamma-Ray Burst Monitor detection
  89. Swift J151857.0-572147: Confirmation of a new galactic transient
  90. GRB 240215A: Swift-XRT afterglow detection
  91. GRB 240303B: Fermi GBM Final Localization
  92. GRB 240303A: Swift detection of a burst
  93. GRB 240225B: Glowbug gamma-ray detection
  94. GRB 240225C: Glowbug gamma-ray detection
  95. GRB 240225A (short): Glowbug gamma-ray detection
  96. GRB 240229A: DDOTI Upper Limits on the Afterglow
  97. GRB 240218A: NOEMA upper limit
  98. GRB 240229A: CALET Gamma-Ray Burst Monitor detection
  99. IceCube-240229A - IceCube observation of a high-energy neutrino candidate track-like event
  100. GRB 240225B: Swift ToO observations

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