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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"

26124 results found.

  1. Swift GRB240305.18: Global MASTER-Net observations report
  2. Swift GRB240305.16: Global MASTER-Net observations report
  3. GRB 240305A: Swift/BAT-GUANO arcminute localization of a burst
  4. GRB 240218A: Chandra Detection and Jet Break Confirmation
  5. Swift Trigger 1218701: Yes, we triggered on Swift J151857.0-572147 again
  6. Swift Trigger 1218696: Another trigger on Swift J151857.0-572147
  7. GRB240218A: ATCA observation of the radio counterpart
  8. Swift Trigger 1218645: Another detection of Swift J151857.0-572147
  9. Swift J151857.0-572147: Swift-BAT refined analysis
  10. GRB 240225B: Swift-XRT afterglow detection
  11. Swift detection of Swift J151857.0-572147
  12. Swift GRB 240303A: Global MASTER-Net observations report
  13. Swift J151857.0-572147: Confirmation of a new galactic transient
  14. GRB 240215A: Swift-XRT afterglow detection
  15. GRB 240303A: Swift detection of a burst
  16. GRB 240225A (short): Glowbug gamma-ray detection
  17. GRB 240229A: DDOTI Upper Limits on the Afterglow
  18. GRB 240218A: NOEMA upper limit
  19. Swift BAT Triggers 1218081 and 1218082 are not astrophysical
  20. GRB 240225B: Swift ToO observations
  21. GRB 240225B: VLT/X-shooter redshift
  22. GRB 240225B : MITSuME Akeno optical afterglow candidate detection
  23. GRB 240225B: 3.6m DOT observation
  24. GRB 240225B: Mondy afterglow observations
  25. GRB 240225B: Liverpool Telescope afterglow observations
  26. Swift J1727.8-1613 (GRB 230824A): Madrona Peak Observatory - optical follow-up
  27. Swift Trigger 1217799 is not a GRB
  28. GRB 240225B: Liverpool Telescope optical afterglow observations
  29. GRB 240225B: NOT optical observations
  30. GRB 240218A: CMO SAI NIR upper limit
  31. Swift-BAT triggers 1217733 - 1217736 are not astrophysical events
  32. Swift-BAT triggers 1217729-1217732 are not astrophysical
  33. GRB 240225B: Nanshan/HMT optical afterglow detection
  34. GRB 240225B: Swift-XRT observations
  35. GRB 240225B: GOTO detection of a candidate optical afterglow
  36. Transient EPW20240219aa: REM optical/NIR upper limits
  37. GRB 240222A: ATCA radio observations
  38. GRB 240225B: Tiled Swift observations
  39. Transient EPW20240219aa: Xinglong-2.16m optical upper limit
  40. GRB 240218A: VLA detection
  41. GRB 240225A: Swift/BAT-GUANO detection of a short burst
  42. GRB 240222A: GRBAlpha detection
  43. Swift-BAT triggers 1217218-1217222 are not astrophysical
  44. Transient EPW20240219aa: Mondy optical observations
  45. Insight-HXMT/HE Sub-Threshold Detection of Transient EPW20240219aa
  46. Swift BAT Sub-Threshold Detection of EPW20240219aa
  47. GRB 240222A: GECAM detection of a burst
  48. GRB 240222A: Swift-BAT refined analysis
  49. GRB 240222A: Swift-XRT refined Analysis
  50. Swift-BAT triggers 1216907-1216911 are not astrophysical
  51. GRB 240222A: Fermi GBM Observation
  52. GRB 240222A: Swift/UVOT Upper Limits
  53. Swift GRB 240222A: Global MASTER-Net observations report
  54. Swift Trigger 1216864 is not an astrophysical event
  55. GRB 240222A: REM optical and NIR early-time observations
  56. GRB 240222A: Swift detection of a burst
  57. Swift-BAT triggers 1216751 and 1216753 are not astrophysical events
  58. Swift-BAT triggers 1216743-1216748 are not astrophysical
  59. Swift GRB240221.92: Global MASTER-Net observations report
  60. GRB 240218A: MeerLICHT upper limits
  61. GRB 240215B: Fermi GBM Observation
  62. GRB 240218A: LBT H-band detection
  63. GRB 240218A: Swift-BAT refined analysis
  64. Konus-Wind detection of GRB 240218A
  65. GRB 240218A: Swift-XRT refined Analysis
  66. GRB 240218A: VLT/X-shooter redshift of z = 6.782
  67. GRB 240218A: Fermi GBM Detection
  68. GRB 240215A: Fermi GBM Observation
  69. GRB 240215B: GRBAlpha detection
  70. IPN triangulation of GRB 240209A
  71. GRB 240218A: Enhanced Swift-XRT position
  72. GRB 240218A: REM detection of a NIR afterglow candidate
  73. GRB 240218A : r-band upper limit from Observatoire de Haute-Provence
  74. GRB240218A: VLT/X-shooter upper limits
  75. GRB 240218A: Swift detection of a burst
  76. Swift GRB240218.08: Global MASTER-Net observations report
  77. GRB 240215B: Swift/BAT-GUANO detection of a burst outside the coded FOV
  78. Swift Triggers 12156887-1215690 are not astrophysical events.
  79. GRB 240215A: Tiled Swift observations
  80. GRB 240215A: Swift/BAT-GUANO localization of a burst
  81. GRB240209A: OHP/T193 detection of the GOTO afterglow candidate AT2024cew / GOTO24pw
  82. GRB 240209A: Wendelstein Optical Observations
  83. GRB 240128A: Further Swift-XRT observations
  84. GRB 240214A: Tiled Swift observations
  85. GRB 240214A/1H 0451-560: MAXI/GSC detection
  86. Konus-Wind detection of GRB 240204A
  87. IPN triangulation of GRB 240205A (short)
  88. GRB 240205B: PRIME near infrared detection
  89. Swift Trigger 1213872 is not an astrophysical event
  90. GRB240204A: Swift/UVOT Upper Limits
  91. GRB 240205B: AstroSat CZTI detection
  92. GRB 240205B: Swift-BAT refined analysis
  93. Konus-Wind detection of GRB 240205B (long / very soft)
  94. GRB 240205B: VLT/X-shooter redshift
  95. GRB 240205B: CALET Gamma-Ray Burst Monitor detection
  96. GRB 240205B: BOOTES-6 optical afterglow follow-up
  97. GRB 240205B: ATCA detection of radio counterpart
  98. GRB 240205B: REM detection of the optical/NIR afterglow
  99. GRB 240205B: Fermi GBM Observation
  100. GRB 240204A: AstroSat CZTI detection

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