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GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. 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').
Advanced Search

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"

23734 results found.

  1. LIGO/Virgo/KAGRA S231102i: Global MASTER-Net observations report
  2. GRB 231101A: Glowbug gamma-ray detection
  3. GRB 231024A: GRANDMA observations of AT2023vuc/GOTO23baj candidate
  4. LIGO/Virgo/KAGRA S231102w: Identification of a GW compact binary merger candidate
  5. Fermi trigger No 720498201: Global MASTER-Net observations report
  6. GRB 231030B: GRBAlpha detection
  7. GRB 231028B: VZLUSAT-2 detection
  8. Fermi trigger No 720415645: Global MASTER-Net observations report
  9. GRB 231030B: AstroSat CZTI detection
  10. Fermi GRB 231030B: Global MASTER-Net observations report
  11. IPN triangulation of GRB 231020A
  12. GRB 231028A: Swift-BAT refined analysis
  13. GRB 231028A: CALET Gamma-Ray Burst Monitor detection
  14. Fermi GRB 231030A: Global MASTER-Net observations report
  15. LIGO/Virgo/KAGRA S231029y: One counterpart neutrino candidate from IceCube neutrino searches
  16. LIGO/Virgo/KAGRA S231029ai: Global MASTER-Net observations report
  17. LIGO/Virgo/KAGRA S231029k: Global MASTER-Net observations report
  18. GRB 231028A: AstroSat CZTI detection
  19. GRB 231028A: Glowbug gamma-ray detection
  20. Fermi trigger No 720224759: Global MASTER-Net observations report
  21. Swift GRB 231028A: Global MASTER-Net observations report
  22. LIGO/Virgo/KAGRA S231028bg: Identification of a GW compact binary merger candidate
  23. GRB 231028A: Swift detection of a burst
  24. IceCube Alert 231027.18: Global MASTER-Net observations report
  25. LIGO/Virgo/KAGRA S231025t: Global MASTER-Net observations report
  26. LIGO/Virgo/KAGRA S231025a: Global MASTER-Net observations report
  27. GRB 231019A: Glowbug gamma-ray detection
  28. IC231004A: GRANDMA observations of AT2023uqf/ZTF23abidzvf candidate
  29. GRB 231025A: Fermi GBM Observation
  30. GRB 231024A: X-shooter spectroscopy of AT2023vuc/GOTO23baj reveals a young supernova with flash ionisation features
  31. GRB 231024A: LCOGT and ZTF detections of the GOTO optical counterpart candidate
  32. GRB 231020A: AstroSat CZTI detection
  33. GRB 231020B: AstroSat CZTI detection
  34. GRB 231024A: GOTO optical counterpart candidate
  35. LIGO/Virgo/KAGRA S231025a: two counterpart neutrino candidates from IceCube neutrino searches
  36. Fermi trigger No 719846439: Global MASTER-Net observations report
  37. The photometry of the transient in Messier 31 field: GMG observation
  38. LIGO/Virgo/KAGRA S231021az: Coverage and upper limits from MAXI/GSC observations
  39. GRB 231019A: VZLUSAT-2 detection
  40. GRB 231018A: VZLUSAT-2 detection
  41. Fermi GRB 231020A: Global MASTER-Net observations report
  42. LIGO/Virgo/KAGRA S231020ba: Coverage and upper limits from MAXI/GSC observations
  43. LIGO/Virgo/KAGRA S231020ba: Identification of a GW compact binary merger candidate
  44. GRB 231018A: GRBAlpha detection
  45. GRB 231018A: CALET Gamma-Ray Burst Monitor detection
  46. Fermi GRB 231019A: Global MASTER-Net observations report
  47. GRB 231018A: Glowbug gamma-ray detection
  48. Konus-Wind detection of GRB 231018A
  49. IPN triangulation of GRB 231018A
  50. GRB 231017A: GOTO optical upper limits
  51. LIGO/Virgo/KAGRA S231018cb: One counterpart neutrino candidate event from an IceCube neutrino search
  52. IC231004A: Classification of AT2023uqf/ZTF23abidzvf as a rapidly-evolving supernova with CSM interaction
  53. GRB 231017A: Las Cumbres optical upper limit
  54. GRB 231015A: Glowbug gamma-ray detection
  55. GRB231017A: GROWTH-India upper limits on the optical afterglow
  56. GRB 231015A: AstroSat CZTI detection
  57. GRB 231017A: Swift-XRT observations
  58. GRB 231017A: Swift/BAT-GUANO candidate arcminute localization of a burst
  59. LIGO/Virgo/KAGRA S231014r: Identification of a GW compact binary merger candidate
  60. GRB 231004A: Glowbug gamma-ray detection
  61. LIGO/Virgo/KAGRA S231008ap: Identification of a GW compact binary merger candidate
  62. GRB 231004A: CALET Gamma-Ray Burst Monitor detection
  63. LIGO/Virgo/KAGRA S231005ah: Identification of a GW compact binary merger candidate
  64. LIGO/Virgo/KAGRA S231005j: Identification of a GW compact binary merger candidate
  65. LIGO/Virgo/KAGRA S231001aq: Identification of a GW compact binary merger candidate
  66. LIGO/Virgo/KAGRA S230930al: Identification of a GW compact binary merger candidate
  67. LIGO/Virgo/KAGRA S230928cb: Identification of a GW compact binary merger candidate
  68. LIGO/Virgo/KAGRA S230927be: Identification of a GW compact binary merger candidate
  69. LIGO/Virgo/KAGRA S230927l: Identification of a GW compact binary merger candidate
  70. Konus-Wind detection of GRB 230919A
  71. LIGO/Virgo/KAGRA S230924an: Identification of a GW compact binary merger candidate
  72. LIGO/Virgo/KAGRA S230917af: GRAWITA wide-field observations
  73. LIGO/Virgo/KAGRA S230922q: Identification of a GW compact binary merger candidate
  74. GRB 230918B: VLT/X-shooter classification of AT 2023tbf (GOTO23aky) as a dwarf nova
  75. IPN triangulation of GRB 230919A (short)
  76. GRB 230919A: AstroSat CZTI detection
  77. LIGO/Virgo/KAGRA S230920al: Identification of a GW compact binary merger candidate
  78. LIGO/Virgo/KAGRA S230919bj: Identification of a GW compact binary merger candidate
  79. GRB 230918B: GOTO detection of a fast-rising transient in the GBM localisation region
  80. LIGO/Virgo S230917af: Swift XRT observations, 6 X-ray sources
  81. GRB 230918A (short): Glowbug gamma-ray detection
  82. GRB 230916B: Glowbug gamma-ray detection
  83. GRB 230812B: Radio observations with the uGMRT
  84. LIGO/Virgo/KAGRA S230917af: MAXI/GSC observations
  85. GRB 230915B: Glowbug gamma-ray detection
  86. Swift GRB230916.18: Global MASTER-Net observations report
  87. Fermi trigger No 716572242: Global MASTER-Net observations report
  88. Fermi trigger No 716544961: Global MASTER-Net observations report
  89. GRB 230911D: GRBAlpha detection
  90. Swift GRB230916.19: Global MASTER-Net observations report
  91. Swift GRB230916.18: Global MASTER-Net observations report
  92. Swift Triggers 1192234, 1192235 and 1192236 are not astrophysical events
  93. Swift GRB230916.13: Global MASTER-Net observations report
  94. Swift GRB230916.12: Global MASTER-Net observations report
  95. Swift GRB230916.11: Global MASTER-Net observations report
  96. Swift Trigger 1192233 is not a GRB
  97. Fermi trigger No 716449174: Global MASTER-Net observations report
  98. GRB 230913A: CALET Gamma-Ray Burst Monitor detection
  99. IceCube Alert 230914.22: Global MASTER-Net observations report
  100. Swift Trigger 1192088 is not an astrophysical event

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