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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"

12091 results found.

  1. Fermi-LAT gamma-ray observations of IceCube-231202A
  2. GRB 231205B: r'-band observations from MISTRAL at Observatoire de Haute-Provence
  3. GRB 231206A: GECAM-B detection of a short burst (correction)
  4. GRB 231206A: GECAM-B detection of a short burst
  5. GRB 231205B: Nanshan/HMT optical upper limit
  6. GRB 231205B: GECAM-B detection of a long burst
  7. GRB 231204A: Glowbug gamma-ray detection
  8. GRB 231204A: CALET Gamma-Ray Burst Monitor detection
  9. Fermi-LAT daily aperture light curve of T CrB now available
  10. GRB 231204A: AstroSat CZTI detection
  11. GRB 231205A: GECAM-B detection of a short burst
  12. Fermi trigger No 723435916: Global MASTER-Net observations report
  13. Fermi trigger No 723326169: Global MASTER-Net observations report
  14. LIGO/Virgo/KAGRA S231129ac: Upper limits from Swift/BAT-GUANO
  15. Fermi trigger No 723412808: Global MASTER-Net observations report
  16. GRB 231204A: Fermi GBM Final Real-time Localization
  17. GRB 231203A: Swift/BAT-GUANO detection of a burst outside the coded FOV
  18. Konus-Wind detection of GRB 231129C
  19. Fermi trigger No 723149952: Global MASTER-Net observations report
  20. GRB 231129C: Swift/BAT-GUANO localization of a burst outside the coded FOV
  21. GRB 231129C: Fermi-LAT detection
  22. GRB 231129C: GECAM-B detection of a bright burst
  23. GRB 231129C: AstroSat CZTI detection
  24. GRB 231127A: GRBAlpha detection
  25. GRB 231129C: MAXI/GSC detection
  26. Fermi trigger No 722977823: Global MASTER-Net observations report
  27. GRB 231129B: MAXI/GSC detection
  28. Fermi-LAT gamma-ray observations of IceCube-231125A
  29. GRB 231129A: GECAM-C detection of a long burst
  30. GRB 231129A: INTEGRAL detection of a long GRB
  31. GRB 231127A: AstroSat CZTI detection
  32. GRB 231123B: Swift/BAT-GUANO detection of a burst outside the coded FOV
  33. GRB 231124A: GRBAlpha detection
  34. GRB 231125A: AstroSat CZTI detection of a short burst
  35. GRB 231111A: Optical follow-up observations at Terskol, AbAO, Maidanak, Mondy, Assy
  36. GRB230506B: VIRT optical upper limit
  37. Fermi trigger No 722462310: Global MASTER-Net observations report
  38. GRB 231115A: XMM-Newton observation
  39. GRB 231123A: AstroSat CZTI detection
  40. GRB 231117A: Mondy optical observations
  41. GRB 231118A: REM optical afterglow detection
  42. GRB 231122B: AstroSat CZTI detection
  43. GRB 231122B: Swift/BAT-GUANO detection of a long burst outside the coded FOV
  44. GRB 231117A: Continued GTC Observations
  45. Fermi trigger No 722349867: Global MASTER-Net observations report
  46. GRB 231122A: GECAM detection
  47. GRB 231122B: GECAM detection
  48. GRB 231118A: ATCA detection of radio counterpart
  49. LIGO/Virgo/KAGRA S231118d: Upper limits from Swift/BAT-GUANO
  50. LIGO/Virgo/KAGRA S231118an: Upper limits from Swift/BAT-GUANO
  51. LIGO/Virgo/KAGRA S231114n: Upper limits from Swift/BAT-GUANO
  52. LIGO/Virgo/KAGRA S231113bb: Upper limits from Swift/BAT-GUANO
  53. Konus-Wind detection of GRB 231020A
  54. GRB 231117A: LDT Confirmation of Optical Fading
  55. 231118A: Swift-UVOT Detection
  56. LIGO/Virgo/KAGRA S231119ab: Coverage and upper limits from MAXI/GSC observations
  57. GRB 231120A: Fermi GBM Final Real-time Localization
  58. GRB 231117A: Swift-XRT refined Analysis
  59. GRB 231118A: Swift-XRT refined Analysis
  60. GRB 231118A: AstroSat CZTI detection
  61. GRB 231118A: LCOGT Optical Observations
  62. GRB 231118A: MASTER OT observation
  63. Swift GRB231118.72: Global MASTER-Net observations report
  64. GRB 231115A: JinShan optical upper limits
  65. Konus-Wind detection of GRB 231117A (short/hard)
  66. GRB 231115A: optical observations from INAF observatories
  67. GRB 231117A: AGILE detection of a bright short burst
  68. GRB 231117A: AstroSat CZTI detection of a bright short burst
  69. GRB 231115A: Non-detection of radio emission with CHIME/FRB
  70. GRB 231111A: Swift/UVOT Detection
  71. GRB 231115A: Swift/BAT-GUANO detection of a short burst
  72. Konus-Wind detection of GRB 231115A (a probable Magnetar Giant Flare from M82)
  73. GRB 231115A: GBM/Fermi Observations of a probable Giant Flare of Magnetar
  74. GRB 231115A: Kinder observations with Lulin observatory
  75. GRB231115A: GRANDMA Observations
  76. GECAM-B observation of a short burst from SGR J1555-5402
  77. LIGO/Virgo S231113bw: upper limits from AGILE/MCAL
  78. SGRJ1555-5402: Swift/BAT-GUANO arcminute localization of a SGR flare
  79. LIGO/Virgo/KAGRA S231113cd: Coverage and upper limits from MAXI/GSC observations
  80. LIGO/Virgo/KAGRA S231113bw: Coverage and upper limits from MAXI/GSC observations
  81. LIGO/Virgo/KAGRA S231113bw: Identification of a GW compact binary merger candidate
  82. GRB 231111A: Afterglow redshift from OSIRIS+/GTC
  83. GRB 231110A: AstroSat CZTI detection
  84. GRB 231111A: Leavitt Observatory optical observations
  85. GRB 231111A: Osservatorio Astronomico "Nastro Verde" optical observations with detection of an optical counterpart
  86. GRB 231111A: GECAM-C detection of a long burst (correction)
  87. GRB 231110A: GECAM-B detection (correction)
  88. GRB 231111A: GECAM-C detection of a long burst
  89. GRB 231110A: GECAM detection
  90. GRB 231111A: Swift detection of a burst with an optical counterpart
  91. Swift GRB231111.60: Global MASTER-Net observations report
  92. Swift GRB231110.89: Global MASTER-Net observations report
  93. GRB 231110A: Swift detection of a burst
  94. Fermi GRB 231108A: Global MASTER-Net observations report
  95. Fermi trigger No 721006392: Global MASTER-Net observations report
  96. LIGO/Virgo/KAGRA S231102w: Upper limits from Swift/BAT-GUANO
  97. Fermi GRB 231106A: Global MASTER-Net observations report
  98. Fermi-LAT gamma-ray observations of IceCube-231103A
  99. GRB 231104A: Fermi GBM Observation
  100. Fermi GRB 231103A: Global MASTER-Net observations report

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