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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').
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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"

12089 results found.

  1. GRB 240303C: VZLUSAT-2 detection
  2. Fermi trigger No 731839490: Global MASTER-Net observations report
  3. Fermi-LAT gamma-ray observations of IceCube-240307A
  4. Fermi GRB 240310A: Global MASTER-Net observations report
  5. GRB 240309A: MAXI/GSC detection
  6. Fermi trigger No 731571927: Global MASTER-Net observations report
  7. Konus-Wind detection of GRB 231118A
  8. GRB 240306A: AstroSat CZTI detection
  9. Fermi GRB 240306A: Global MASTER-Net observations report
  10. Fermi GRB 240305A: Global MASTER-Net observations report
  11. GRB 240306A: Swift/BAT-GUANO detection of a burst
  12. Fermi-LAT gamma-ray observations of IceCube-240229A
  13. GRB 240305C: AstroSat CZTI detection of a short burst
  14. Fermi GRB 240305C: Global MASTER-Net observations report
  15. Konus-Wind detection of GRB 240227A (short/hard)
  16. Swift Trigger 1218701: Yes, we triggered on Swift J151857.0-572147 again
  17. Swift Trigger 1218696: Another trigger on Swift J151857.0-572147
  18. Konus-Wind detection of GRB 240303B
  19. GRB 240303B: Fermi GBM Detection
  20. GRB 240225B: Swift-XRT afterglow detection
  21. Fermi trigger No 731161136: Global MASTER-Net observations report
  22. GRB 240303C: BALROG localization (Fermi Trigger 731189113 / GRB 240303837)
  23. GRB 240225B: Glowbug gamma-ray detection
  24. GRB 240225A (short): Glowbug gamma-ray detection
  25. Konus-Wind detection of GRB 240225B (long)
  26. GRB 240225B: SAO RAS optical observations
  27. IPN triangulation of GRB 240227A (short)
  28. GRB 240225B: Liverpool Telescope optical afterglow observations
  29. GRB 240225B: CALET Gamma-Ray Burst Monitor detection
  30. Transient EPW20240219aa: REM optical/NIR upper limits
  31. GRB 240225B: AstroSat CZTI detection
  32. GRB 240225B: MAXI/GSC detection
  33. GRB 240225A: Swift/BAT-GUANO detection of a short burst
  34. Transient EPW20240219aa: 7DT Optical Upper Limits
  35. VLA X-band observation of EPW20240219aa
  36. Transient EPW20240219aa: Mondy optical observations
  37. Transient EPW20240219aa: Liverpool Telescope non-detection and limiting magnitude
  38. GRB 240222A: Swift detection of a burst
  39. Swift GRB240221.92: Global MASTER-Net observations report
  40. GRB 240215B: Fermi GBM Observation
  41. GRB 240218A: LBT H-band detection
  42. Fermi GRB 240220A: Global MASTER-Net observations report
  43. GRB 240220A: Fermi GBM Final Real-time Localization
  44. Konus-Wind detection of GRB 240218A
  45. GRB 240218A: Swift-XRT refined Analysis
  46. GRB 240218A: Fermi GBM Detection
  47. IPN triangulation of GRB 240209A
  48. Fermi trigger No 729914426: Global MASTER-Net observations report
  49. Gamma-ray flaring activity from the blazar 1ES 1959+650 observed by the Fermi-LAT
  50. GRB 240213A: GRBAlpha detection
  51. GRB 240215B: Swift/BAT-GUANO detection of a burst outside the coded FOV
  52. GRB 240213A: Glowbug gamma-ray detection
  53. GRB240209A: OHP/T193 detection of the GOTO afterglow candidate AT2024cew / GOTO24pw
  54. GRB 240214A/1H 0451-560: MAXI/GSC detection
  55. GRB 240213A: BALROG localization (Fermi Trigger / GRB 240213841)
  56. Fermi GRB 240213A: Global MASTER-Net observations report
  57. GRB 240213A: Fermi GBM Final Real-time Localization
  58. Konus-Wind detection of GRB 240204A
  59. Konus-Wind detection of GRB 240205A (short)
  60. Fermi trigger No 729152364: Global MASTER-Net observations report
  61. IPN triangulation of GRB 240205A (short)
  62. Fermi-LAT gamma-ray observations of IceCube-240204A
  63. GRB 240205A (short): Glowbug gamma-ray detection
  64. GRB 240205B: AstroSat CZTI detection
  65. Fermi trigger No 729012023: Global MASTER-Net observations report
  66. Konus-Wind detection of GRB 240205B (long / very soft)
  67. GRB 240207A: Fermi GBM Final Real-time Localization
  68. Konus-Wind detection of GRB 240125A
  69. GRB 240205B: BOOTES-6 optical afterglow follow-up
  70. GRB 240204A: AstroSat CZTI detection
  71. GRB 240204A: Swift-BAT refined analysis
  72. Fermi trigger No 728749569: Global MASTER-Net observations report
  73. Swift GRB240205.93: Global MASTER-Net observations report
  74. GRB 240205A: Fermi GBM Final Real-time Localization
  75. GRB 240204A: optical afterglow detection with LCOGT 1m telescopes at Sutherland and Teide Observatories
  76. Fermi trigger No 728706420: Global MASTER-Net observations report
  77. IceCube Alert 240204.38: Global MASTER-Net observations report
  78. Konus-Wind detection of GRB 240124B
  79. Konus-Wind detection of GRB 240123C
  80. GRB 240201A: AstroSat CZTI detection
  81. IPN triangulation of GRB 240125B (short)
  82. GRB 240129A: Swift/BAT-GUANO detection of a burst outside the coded FOV
  83. GRB 240128A: Swift-XRT observations
  84. GRB 240128A: MAXI/GSC detection
  85. GRB 240122A: ATCA detection of radio counterpart
  86. GRB 240125A: AstroSat CZTI detection of a short burst
  87. GRB 240124B: AstroSat CZTI detection
  88. GRB 240123C: AstroSat CZTI detection
  89. GRB 240125B: Fermi GBM Final Localization
  90. GRB 240123B: Swift/BAT-GUANO detection of a long burst
  91. Fermi-LAT gamma-ray observations of IceCube-240123A
  92. Fermi GRB 240123B: Global MASTER-Net observations report
  93. GRB 240123A: Swift-XRT refined Analysis
  94. GRB 240123A: Mondy optical afterglow observations
  95. Konus-Wind detection of GRB 240112A
  96. GRB 240123A: Swift detection of a burst with a possible optical counterpart
  97. Swift GRB240123.46: Global MASTER-Net observations report
  98. Konus-Wind detection of GRB 240119A (short/hard)
  99. GRB 240122A: MAXI/GSC detection
  100. GRB 240119A: GECAM detection of a short burst

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