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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.

Advanced Search Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

19611 results found.

  1. GRB 240414A: Enhanced Swift-XRT position
  2. GRB 240414A: MarSEC Observatory, Vicenza, Italy, UPPER LIMIT
  3. GRB 240414A: Skynet Optical Afterglow Observations
  4. Swift GRB 240414A: Global MASTER-Net observations report
  5. IPN triangulation of GRB 240410A
  6. IPN triangulation of GRB 240411A
  7. GRB 240414A : MITSuME Akeno optical upper limits
  8. GRB 240414A: Swift detection of a burst
  9. GRB 240411B: Swift-BAT refined analysis
  10. GRB 240411B: Swift-XRT refined Analysis
  11. GRB 240411B: 1.3m DFOT Optical observations
  12. GRB 240411B: Enhanced Swift-XRT position
  13. GRB 240411B: Swift detection of a burst
  14. EP240408A: MASTER optical observations
  15. EP240408a: GROND detection of a candidate counterpart
  16. EP240408a: Swift follow-up observation
  17. Swift Trigger 1220736: detection of 4U 1543-62.
  18. Swift satellite resumes pointed science observations
  19. GRB 240318A: Fermi GBM Observation
  20. Konus-Wind detection of GRB 240315C (possible counterpart of EP240315a)
  21. GRB 240315C / X-ray transient EP240315a: Swift/BAT detection
  22. GRB 240318A: Swift/BAT-GUANO detection of a burst outside the coded FOV
  23. IPN triangulation of GRB 240315C (consistent with a fast X-ray transient EP240315a)
  24. GRB 240317B: Swift/BAT-GUANO Angular Error Correction
  25. GRB 240317B: Fermi GBM Observation
  26. Swift satellite in safe mode
  27. GRB 240317B: Swift/BAT-GUANO arcminute localization of a burst
  28. Einstein Probe detected of a fast X-ray transient EP240315a
  29. GRID detection of GRB 240306A
  30. Swift Triggers 1220155, 1220156, 1220157, 1220158, 1220160 and 1220161 were not astrophysical
  31. Swift Triggers 1220093, 1220094, 1220095 and 1220096 are not astrophysical
  32. Swift Triggers 1220090, 1220091 and 1220092 are not astrophysical
  33. Swift triggers 1219917, 1219917 and 1219922 were not astrophysical
  34. Swift Trigger 1219909 and 1219910 are not a astrophysical
  35. Swift Trigger 1219905 is not a GRB
  36. Swift Trigger 1219874 is not astrophysical
  37. Swift GRB240309.61: Global MASTER-Net observations report
  38. Swift Trigger 1219325 is not a GRB
  39. GRB 240306A: Fermi GBM observation
  40. Konus-Wind detection of GRB 231118A
  41. GRB 240306A: AstroSat CZTI detection
  42. GRB 240306A: Swift/BAT-GUANO detection of a burst
  43. GRB 240305A: Fermi GBM observation
  44. Swift GRB240305.18: Global MASTER-Net observations report
  45. Swift GRB240305.16: Global MASTER-Net observations report
  46. GRB 240305A: Swift/BAT-GUANO arcminute localization of a burst
  47. GRB 240218A: Chandra Detection and Jet Break Confirmation
  48. Swift Trigger 1218701: Yes, we triggered on Swift J151857.0-572147 again
  49. Swift Trigger 1218696: Another trigger on Swift J151857.0-572147
  50. Swift Trigger 1218645: Another detection of Swift J151857.0-572147
  51. Swift J151857.0-572147: Swift-BAT refined analysis
  52. GRB 240225B: Swift-XRT afterglow detection
  53. Swift detection of Swift J151857.0-572147
  54. Swift GRB 240303A: Global MASTER-Net observations report
  55. Swift J151857.0-572147: Confirmation of a new galactic transient
  56. GRB 240215A: Swift-XRT afterglow detection
  57. GRB 240303A: Swift detection of a burst
  58. GRB 240225A (short): Glowbug gamma-ray detection
  59. Swift BAT Triggers 1218081 and 1218082 are not astrophysical
  60. GRB 240225B: Swift ToO observations
  61. GRB 240225B: 3.6m DOT observation
  62. Swift J1727.8-1613 (GRB 230824A): Madrona Peak Observatory - optical follow-up
  63. Swift Trigger 1217799 is not a GRB
  64. Swift-BAT triggers 1217733 - 1217736 are not astrophysical events
  65. Swift-BAT triggers 1217729-1217732 are not astrophysical
  66. GRB 240225B: Nanshan/HMT optical afterglow detection
  67. GRB 240225B: Swift-XRT observations
  68. GRB 240225B: GOTO detection of a candidate optical afterglow
  69. GRB 240225B: Tiled Swift observations
  70. Transient EPW20240219aa: Xinglong-2.16m optical upper limit
  71. GRB 240225A: Swift/BAT-GUANO detection of a short burst
  72. GRB 240222A: GRBAlpha detection
  73. Swift-BAT triggers 1217218-1217222 are not astrophysical
  74. Transient EPW20240219aa: Mondy optical observations
  75. Insight-HXMT/HE Sub-Threshold Detection of Transient EPW20240219aa
  76. Swift BAT Sub-Threshold Detection of EPW20240219aa
  77. GRB 240222A: GECAM detection of a burst
  78. GRB 240222A: Swift-BAT refined analysis
  79. GRB 240222A: Swift-XRT refined Analysis
  80. Swift-BAT triggers 1216907-1216911 are not astrophysical
  81. GRB 240222A: Fermi GBM Observation
  82. GRB 240222A: Swift/UVOT Upper Limits
  83. Swift GRB 240222A: Global MASTER-Net observations report
  84. Swift Trigger 1216864 is not an astrophysical event
  85. GRB 240222A: Swift detection of a burst
  86. Swift-BAT triggers 1216751 and 1216753 are not astrophysical events
  87. Swift-BAT triggers 1216743-1216748 are not astrophysical
  88. Swift GRB240221.92: Global MASTER-Net observations report
  89. GRB 240218A: MeerLICHT upper limits
  90. GRB 240215B: Fermi GBM Observation
  91. GRB 240218A: LBT H-band detection
  92. GRB 240218A: Swift-BAT refined analysis
  93. Konus-Wind detection of GRB 240218A
  94. GRB 240218A: Swift-XRT refined Analysis
  95. GRB 240218A: VLT/X-shooter redshift of z = 6.782
  96. GRB 240218A: Fermi GBM Detection
  97. GRB 240215A: Fermi GBM Observation
  98. GRB 240215B: GRBAlpha detection
  99. IPN triangulation of GRB 240209A
  100. GRB 240218A: Enhanced Swift-XRT position

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