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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"

11756 results found.

  1. GRB 231129C: Fermi-LAT detection
  2. GRB 231129C: GECAM-B detection of a bright burst
  3. GRB 231129C: AstroSat CZTI detection
  4. GRB 231127A: GRBAlpha detection
  5. GRB 231129C: MAXI/GSC detection
  6. Fermi trigger No 722977823: Global MASTER-Net observations report
  7. GRB 231129B: MAXI/GSC detection
  8. Fermi-LAT gamma-ray observations of IceCube-231125A
  9. GRB 231129A: GECAM-C detection of a long burst
  10. GRB 231129A: INTEGRAL detection of a long GRB
  11. GRB 231127A: AstroSat CZTI detection
  12. GRB 231123B: Swift/BAT-GUANO detection of a burst outside the coded FOV
  13. GRB 231124A: GRBAlpha detection
  14. GRB 231125A: AstroSat CZTI detection of a short burst
  15. GRB 231111A: Optical follow-up observations at Terskol, AbAO, Maidanak, Mondy, Assy
  16. GRB230506B: VIRT optical upper limit
  17. Fermi trigger No 722462310: Global MASTER-Net observations report
  18. GRB 231115A: XMM-Newton observation
  19. GRB 231123A: AstroSat CZTI detection
  20. GRB 231117A: Mondy optical observations
  21. GRB 231118A: REM optical afterglow detection
  22. GRB 231122B: AstroSat CZTI detection
  23. GRB 231122B: Swift/BAT-GUANO detection of a long burst outside the coded FOV
  24. GRB 231117A: Continued GTC Observations
  25. Fermi trigger No 722349867: Global MASTER-Net observations report
  26. GRB 231122A: GECAM detection
  27. GRB 231122B: GECAM detection
  28. GRB 231118A: ATCA detection of radio counterpart
  29. LIGO/Virgo/KAGRA S231118d: Upper limits from Swift/BAT-GUANO
  30. LIGO/Virgo/KAGRA S231118an: Upper limits from Swift/BAT-GUANO
  31. LIGO/Virgo/KAGRA S231114n: Upper limits from Swift/BAT-GUANO
  32. LIGO/Virgo/KAGRA S231113bb: Upper limits from Swift/BAT-GUANO
  33. Konus-Wind detection of GRB 231020A
  34. GRB 231117A: LDT Confirmation of Optical Fading
  35. 231118A: Swift-UVOT Detection
  36. LIGO/Virgo/KAGRA S231119ab: Coverage and upper limits from MAXI/GSC observations
  37. GRB 231120A: Fermi GBM Final Real-time Localization
  38. GRB 231117A: Swift-XRT refined Analysis
  39. GRB 231118A: Swift-XRT refined Analysis
  40. GRB 231118A: AstroSat CZTI detection
  41. GRB 231118A: LCOGT Optical Observations
  42. GRB 231118A: MASTER OT observation
  43. Swift GRB231118.72: Global MASTER-Net observations report
  44. GRB 231115A: JinShan optical upper limits
  45. Konus-Wind detection of GRB 231117A (short/hard)
  46. GRB 231115A: optical observations from INAF observatories
  47. GRB 231117A: AGILE detection of a bright short burst
  48. GRB 231117A: AstroSat CZTI detection of a bright short burst
  49. GRB 231115A: Non-detection of radio emission with CHIME/FRB
  50. GRB 231111A: Swift/UVOT Detection
  51. GRB 231115A: Swift/BAT-GUANO detection of a short burst
  52. Konus-Wind detection of GRB 231115A (a probable Magnetar Giant Flare from M82)
  53. GRB 231115A: Kinder observations with Lulin observatory
  54. GRB231115A: GRANDMA Observations
  55. LIGO/Virgo S231113bw: upper limits from AGILE/MCAL
  56. LIGO/Virgo/KAGRA S231113cd: Coverage and upper limits from MAXI/GSC observations
  57. LIGO/Virgo/KAGRA S231113bw: Coverage and upper limits from MAXI/GSC observations
  58. LIGO/Virgo/KAGRA S231113bw: Identification of a GW compact binary merger candidate
  59. GRB 231111A: Afterglow redshift from OSIRIS+/GTC
  60. GRB 231110A: AstroSat CZTI detection
  61. GRB 231111A: Leavitt Observatory optical observations
  62. GRB 231111A: Osservatorio Astronomico "Nastro Verde" optical observations with detection of an optical counterpart
  63. GRB 231111A: GECAM-C detection of a long burst (correction)
  64. GRB 231110A: GECAM-B detection (correction)
  65. GRB 231111A: GECAM-C detection of a long burst
  66. GRB 231110A: GECAM detection
  67. GRB 231111A: Swift detection of a burst with an optical counterpart
  68. Swift GRB231111.60: Global MASTER-Net observations report
  69. Swift GRB231110.89: Global MASTER-Net observations report
  70. GRB 231110A: Swift detection of a burst
  71. Fermi GRB 231108A: Global MASTER-Net observations report
  72. Fermi trigger No 721006392: Global MASTER-Net observations report
  73. LIGO/Virgo/KAGRA S231102w: Upper limits from Swift/BAT-GUANO
  74. Fermi GRB 231106A: Global MASTER-Net observations report
  75. Fermi-LAT gamma-ray observations of IceCube-231103A
  76. GRB 231104A: Fermi GBM Observation
  77. Fermi GRB 231103A: Global MASTER-Net observations report
  78. GRB 231104A: AstroSat CZTI detection
  79. GRB 231104A: Fermi-LAT detection
  80. GRB 231104A: Swift/UVOT Upper Limits
  81. Swift GRB231104.07: Global MASTER-Net observations report
  82. Fermi-LAT gamma-ray observations of IceCube-231027A
  83. Fermi trigger No 720498201: Global MASTER-Net observations report
  84. GRB 231030B: GRBAlpha detection
  85. GRB 231030B: Fermi GBM Detection
  86. GRB 231030B: AstroSat CZTI detection
  87. Fermi GRB 231030B: Global MASTER-Net observations report
  88. LIGO/Virgo/KAGRA S231029y: Upper limits from Swift/BAT-GUANO
  89. LIGO/Virgo/KAGRA S231029ai: Global MASTER-Net observations report
  90. GRID detection of GRB 231020A
  91. GRB 231028A: AstroSat CZTI detection
  92. Fermi trigger No 720224759: Global MASTER-Net observations report
  93. Swift GRB 231028A: Global MASTER-Net observations report
  94. IceCube Alert 231027.18: Global MASTER-Net observations report
  95. LIGO/Virgo/KAGRA S231025t: Global MASTER-Net observations report
  96. LIGO/Virgo/KAGRA S231025a: Global MASTER-Net observations report
  97. IC231004A: GRANDMA observations of AT2023uqf/ZTF23abidzvf candidate
  98. GRB 231024A: Fermi GBM Observation
  99. GRB 231020A: AstroSat CZTI detection
  100. GRB 231020B: AstroSat CZTI detection

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