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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"

12113 results found.

  1. LIGO/Virgo/KAGRA S231113cd: Coverage and upper limits from MAXI/GSC observations
  2. LIGO/Virgo/KAGRA S231113bw: Coverage and upper limits from MAXI/GSC observations
  3. LIGO/Virgo/KAGRA S231113bw: Identification of a GW compact binary merger candidate
  4. GRB 231111A: Afterglow redshift from OSIRIS+/GTC
  5. GRB 231110A: AstroSat CZTI detection
  6. GRB 231111A: Leavitt Observatory optical observations
  7. GRB 231111A: Osservatorio Astronomico "Nastro Verde" optical observations with detection of an optical counterpart
  8. GRB 231111A: GECAM-C detection of a long burst (correction)
  9. GRB 231110A: GECAM-B detection (correction)
  10. GRB 231111A: GECAM-C detection of a long burst
  11. GRB 231110A: GECAM detection
  12. GRB 231111A: Swift detection of a burst with an optical counterpart
  13. Swift GRB231111.60: Global MASTER-Net observations report
  14. Swift GRB231110.89: Global MASTER-Net observations report
  15. GRB 231110A: Swift detection of a burst
  16. Fermi GRB 231108A: Global MASTER-Net observations report
  17. Fermi trigger No 721006392: Global MASTER-Net observations report
  18. LIGO/Virgo/KAGRA S231102w: Upper limits from Swift/BAT-GUANO
  19. Fermi GRB 231106A: Global MASTER-Net observations report
  20. Fermi-LAT gamma-ray observations of IceCube-231103A
  21. GRB 231104A: Fermi GBM Observation
  22. Fermi GRB 231103A: Global MASTER-Net observations report
  23. GRB 231104A: AstroSat CZTI detection
  24. GRB 231104A: Fermi-LAT detection
  25. GRB 231104A: Swift/UVOT Upper Limits
  26. Swift GRB231104.07: Global MASTER-Net observations report
  27. Fermi-LAT gamma-ray observations of IceCube-231027A
  28. Fermi trigger No 720498201: Global MASTER-Net observations report
  29. GRB 231030B: GRBAlpha detection
  30. GRB 231030B: Fermi GBM Detection
  31. GRB 231030B: AstroSat CZTI detection
  32. Fermi GRB 231030B: Global MASTER-Net observations report
  33. LIGO/Virgo/KAGRA S231029y: Upper limits from Swift/BAT-GUANO
  34. LIGO/Virgo/KAGRA S231029ai: Global MASTER-Net observations report
  35. GRID detection of GRB 231020A
  36. GRB 231028A: AstroSat CZTI detection
  37. Fermi trigger No 720224759: Global MASTER-Net observations report
  38. Swift GRB 231028A: Global MASTER-Net observations report
  39. IceCube Alert 231027.18: Global MASTER-Net observations report
  40. LIGO/Virgo/KAGRA S231025t: Global MASTER-Net observations report
  41. LIGO/Virgo/KAGRA S231025a: Global MASTER-Net observations report
  42. IC231004A: GRANDMA observations of AT2023uqf/ZTF23abidzvf candidate
  43. GRB 231024A: Fermi GBM Observation
  44. GRB 231020A: AstroSat CZTI detection
  45. GRB 231020B: AstroSat CZTI detection
  46. GRB 231024A: Fermi GBM Final Localization
  47. Fermi trigger No 719846439: Global MASTER-Net observations report
  48. The photometry of the transient in Messier 31 field: GMG observation
  49. GRB 231018A: Swift/BAT-GUANO detection of a long burst outside the coded FOV
  50. LIGO/Virgo/KAGRA S231020bw: Upper limits from Swift/BAT-GUANO
  51. LIGO/Virgo/KAGRA S231021az: Coverage and upper limits from MAXI/GSC observations
  52. GRB 231020A: Fermi GBM Detection
  53. GRB 231017A: Mondy optical observations. A possible candidate for an afterglow or host galaxy.
  54. GRB 231020B: BALROG localization (Fermi Trigger 719530557 / GRB 231020900)
  55. GRB 231020B: Fermi GBM Final Real-time Localization
  56. GRB 231020A: BALROG localization (Fermi Trigger / GRB 231020790)
  57. Fermi GRB 231020A: Global MASTER-Net observations report
  58. LIGO/Virgo/KAGRA S231020bw: Identification of a GW compact binary merger candidate
  59. GRB 231020A: Fermi GBM Final Real-time Localization
  60. LIGO/Virgo/KAGRA S231020ba: Coverage and upper limits from MAXI/GSC observations
  61. LIGO/Virgo/KAGRA S231020ba: Identification of a GW compact binary merger candidate
  62. Konus-Wind detection of GRB 231018A
  63. GRB 231017A: GOTO optical upper limits
  64. GRB 231015A: AstroSat CZTI detection
  65. GRB 231017A: Swift/BAT-GUANO candidate arcminute localization of a burst
  66. Fermi-LAT gamma-ray observations of IceCube-231014A
  67. LIGO/Virgo/KAGRA S231014r: Upper limits from Swift/BAT-GUANO
  68. GRB 231012A: Fermi GBM Final Real-time Localization
  69. LIGO/Virgo/KAGRA S231005j: Upper limits from Swift/BAT-GUANO
  70. LIGO/Virgo/KAGRA S231008ap: Identification of a GW compact binary merger candidate
  71. Fermi-LAT gamma-ray observations of IceCube-231004A
  72. LIGO/Virgo/KAGRA S231001aq: Upper limits from Swift/BAT-GUANO
  73. LIGO/Virgo/KAGRA S230930al: Upper limits from Swift/BAT-GUANO
  74. LIGO/Virgo/KAGRA S230928cb: Upper limits from Swift/BAT-GUANO
  75. AMON Coincidence Alert from the sub-threshold IceCube-HAWC search NuEm-230927A
  76. Konus-Wind detection of GRB 230919A
  77. LIGO/Virgo/KAGRA S230924an: Upper limits from Swift/BAT-GUANO
  78. LIGO/Virgo/KAGRA S230920al: Upper limits from Swift/BAT-GUANO
  79. LIGO/Virgo/KAGRA S230919bj: Upper limits from Swift/BAT-GUANO
  80. LIGO/Virgo/KAGRA S230922g: DECam GW-MMADS candidates
  81. GRB 230812B: r'-band observations from MISTRAL at Observatoire de Haute-Provence
  82. LIGO/Virgo/KAGRA S230917af: GRAWITA wide-field observations
  83. GRB 230919A: Swift/BAT-GUANO detection of a possibly short burst outside the coded FOV
  84. GRB 230812B : optical observations from MISTRAL at Observatoire de Haute-Provence
  85. GRB 230919A: AstroSat CZTI detection
  86. LIGO/Virgo/KAGRA S230920al: Identification of a GW compact binary merger candidate
  87. GRB 230918B: GOTO detection of a fast-rising transient in the GBM localisation region
  88. LIGO/Virgo S230917af: Swift XRT observations, 6 X-ray sources
  89. GRB 230917A: AstroSat CZTI detection
  90. LIGO/Virgo/KAGRA S230917af: MAXI/GSC observations
  91. Fermi trigger No 716572242: Global MASTER-Net observations report
  92. Fermi-LAT gamma-ray observations of IceCube-230914A
  93. LIGO/Virgo/KAGRA S230914ak: Upper limits from Swift/BAT-GUANO
  94. Swift GRB230916.11: Global MASTER-Net observations report
  95. Fermi trigger No 716449174: Global MASTER-Net observations report
  96. Fermi trigger No 716419312: Global MASTER-Net observations report
  97. GRB 230913A: Fermi GBM Observation
  98. Swift GRB230913.70: Global MASTER-Net observations report
  99. GRB 230911B: AstroSat CZTI detection
  100. GRB 230911C: Swift-XRT refined Analysis

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