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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 231024A: Fermi GBM Final Localization
  2. Fermi trigger No 719846439: Global MASTER-Net observations report
  3. The photometry of the transient in Messier 31 field: GMG observation
  4. GRB 231018A: Swift/BAT-GUANO detection of a long burst outside the coded FOV
  5. LIGO/Virgo/KAGRA S231020bw: Upper limits from Swift/BAT-GUANO
  6. LIGO/Virgo/KAGRA S231021az: Coverage and upper limits from MAXI/GSC observations
  7. GRB 231020A: Fermi GBM Detection
  8. GRB 231017A: Mondy optical observations. A possible candidate for an afterglow or host galaxy.
  9. GRB 231020B: BALROG localization (Fermi Trigger 719530557 / GRB 231020900)
  10. GRB 231020B: Fermi GBM Final Real-time Localization
  11. GRB 231020A: BALROG localization (Fermi Trigger / GRB 231020790)
  12. Fermi GRB 231020A: Global MASTER-Net observations report
  13. LIGO/Virgo/KAGRA S231020bw: Identification of a GW compact binary merger candidate
  14. GRB 231020A: Fermi GBM Final Real-time Localization
  15. LIGO/Virgo/KAGRA S231020ba: Coverage and upper limits from MAXI/GSC observations
  16. LIGO/Virgo/KAGRA S231020ba: Identification of a GW compact binary merger candidate
  17. Konus-Wind detection of GRB 231018A
  18. GRB 231017A: GOTO optical upper limits
  19. GRB 231015A: AstroSat CZTI detection
  20. GRB 231017A: Swift/BAT-GUANO candidate arcminute localization of a burst
  21. Fermi-LAT gamma-ray observations of IceCube-231014A
  22. LIGO/Virgo/KAGRA S231014r: Upper limits from Swift/BAT-GUANO
  23. GRB 231012A: Fermi GBM Final Real-time Localization
  24. LIGO/Virgo/KAGRA S231005j: Upper limits from Swift/BAT-GUANO
  25. LIGO/Virgo/KAGRA S231008ap: Identification of a GW compact binary merger candidate
  26. Fermi-LAT gamma-ray observations of IceCube-231004A
  27. LIGO/Virgo/KAGRA S231001aq: Upper limits from Swift/BAT-GUANO
  28. LIGO/Virgo/KAGRA S230930al: Upper limits from Swift/BAT-GUANO
  29. LIGO/Virgo/KAGRA S230928cb: Upper limits from Swift/BAT-GUANO
  30. AMON Coincidence Alert from the sub-threshold IceCube-HAWC search NuEm-230927A
  31. Konus-Wind detection of GRB 230919A
  32. LIGO/Virgo/KAGRA S230924an: Upper limits from Swift/BAT-GUANO
  33. LIGO/Virgo/KAGRA S230920al: Upper limits from Swift/BAT-GUANO
  34. LIGO/Virgo/KAGRA S230919bj: Upper limits from Swift/BAT-GUANO
  35. LIGO/Virgo/KAGRA S230922g: DECam GW-MMADS candidates
  36. GRB 230812B: r'-band observations from MISTRAL at Observatoire de Haute-Provence
  37. LIGO/Virgo/KAGRA S230917af: GRAWITA wide-field observations
  38. GRB 230919A: Swift/BAT-GUANO detection of a possibly short burst outside the coded FOV
  39. GRB 230812B : optical observations from MISTRAL at Observatoire de Haute-Provence
  40. GRB 230919A: AstroSat CZTI detection
  41. LIGO/Virgo/KAGRA S230920al: Identification of a GW compact binary merger candidate
  42. GRB 230918B: GOTO detection of a fast-rising transient in the GBM localisation region
  43. LIGO/Virgo S230917af: Swift XRT observations, 6 X-ray sources
  44. GRB 230917A: AstroSat CZTI detection
  45. LIGO/Virgo/KAGRA S230917af: MAXI/GSC observations
  46. Fermi trigger No 716572242: Global MASTER-Net observations report
  47. Fermi-LAT gamma-ray observations of IceCube-230914A
  48. LIGO/Virgo/KAGRA S230914ak: Upper limits from Swift/BAT-GUANO
  49. Swift GRB230916.11: Global MASTER-Net observations report
  50. Fermi trigger No 716449174: Global MASTER-Net observations report
  51. Fermi trigger No 716419312: Global MASTER-Net observations report
  52. GRB 230913A: Fermi GBM Observation
  53. Swift GRB230913.70: Global MASTER-Net observations report
  54. GRB 230911B: AstroSat CZTI detection
  55. GRB 230911C: Swift-XRT refined Analysis
  56. GRB 230911D: Fermi-LAT detection
  57. GRB230911C: LCOGT Optical Upper Limits
  58. GRB 230908A: Swift/BAT-GUANO detection of a long burst outside the coded FOV
  59. Konus-Wind detection of GRB 230811D
  60. GRB 230911C: Swift detection of a burst
  61. GRB 230906A: AstroSat CZTI detection
  62. GRB 230908A: GRBAlpha detection
  63. GRB 230908A: AstroSat CZTI detection
  64. Konus-Wind detection of GRB 230906A (short)
  65. IPN triangulation of GRB 230906A (short)
  66. GRB 230905B: AstroSat CZTI detection
  67. Fermi GRB 230906A: Global MASTER-Net observations report
  68. GRB 230905B: GECAM-C detection of a long burst
  69. GRB 230903A: Swift-XRT refined Analysis
  70. GRB 230904C: Fermi GBM Final Localization
  71. Fermi trigger No 715552087: Global MASTER-Net observations report
  72. Fermi trigger No 715429986: Global MASTER-Net observations report
  73. GRB 230903A: LCOGT Optical Upper Limits
  74. GRB 230903A: Swift detection of a burst
  75. Swift GRB230903.72: Global MASTER-Net observations report
  76. GRB 230828A: AstroSat CZTI detection
  77. GRB 230827A: Swift/BAT-GUANO detection of a burst outside the coded FOV
  78. Fermi trigger No 714809315: Global MASTER-Net observations report
  79. Fermi GRB 230827A: Global MASTER-Net observations report
  80. Swift J1727.8-1613 (GRB 230824A): Leavitt Observatory optical observations
  81. GRB 230826A: Mondy optical observations
  82. Swift GRB230826.81: Global MASTER-Net observations report
  83. LIGO/Virgo/KAGRA S230825k: Upper limits from Swift/BAT-GUANO
  84. Swift J1727.8-1613 (GRB 230824A): Skynet Optical Observations
  85. Trigger 1187207: Swift detection of Swift J1727.8-1613 (AKA GRB 230824A)
  86. Trigger 1187203: Swift detection of Swift J1727.8-1613 (AKA GRB 230824A)
  87. Trigger 1187142: Swift detection of Swift J1727.8-1613 (AKA GRB 230824A)
  88. MAXI/GSC detection of Swift J1727.8-1613 (GRB 230824A)
  89. IBAS trigger 10375 is not a GRB
  90. Integral GRB230824.72: Global MASTER-Net observations report
  91. GRB 230824B: AstroSat CZTI detection
  92. GRB 230824A: Swift detection of a burst
  93. LIGO/Virgo/KAGRA S230822bm: Upper limits from Swift/BAT-GUANO
  94. GRB 230818B: AstroSat CZTI detection
  95. GRB 230812B: Assy optical observations, possible SN rise
  96. GRB 230812B: SAO RAS RC-500 and Zeiss-1000 observations
  97. Konus-Wind detection of GRB 230818A
  98. GRB 230820A: AstroSat CZTI detection
  99. LIGO/Virgo/KAGRA S230820bq: Identification of a GW compact binary merger candidate
  100. Swift GRB230820.82: Global MASTER-Net observations report

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