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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"

37770 results found.

  1. GRB 240229A: VZLUSAT-2 detection
  2. Improved IPN triangulation of GRB 240227A (short)
  3. IPN triangulation of GRB 240229A
  4. GRB 240305A: Fermi GBM Final Real-time Localization
  5. Konus-Wind detection of GRB 240303B
  6. IPN triangulation of GRB 240303B
  7. GRB 240303B: Fermi GBM Detection
  8. GRB 240225B: Swift-XRT afterglow detection
  9. Swift detection of Swift J151857.0-572147
  10. GRB 240303B: CALET Gamma-Ray Burst Monitor detection
  11. Fermi trigger No 731161136: Global MASTER-Net observations report
  12. GRB 240303C: BALROG localization (Fermi Trigger 731189113 / GRB 240303837)
  13. Swift GRB 240303A: Global MASTER-Net observations report
  14. Swift J151857.0-572147: Confirmation of a new galactic transient
  15. GRB 240215A: Swift-XRT afterglow detection
  16. GRB 240303B: BALROG localization (Fermi Trigger 731161136 / GRB 240303513)
  17. GRB 240303B: Fermi GBM Final Localization
  18. GRB 240303A: Swift detection of a burst
  19. GRB 240225B: Glowbug gamma-ray detection
  20. GRB 240225C: Glowbug gamma-ray detection
  21. GRB 240225A (short): Glowbug gamma-ray detection
  22. GRB 240229A: DDOTI Upper Limits on the Afterglow
  23. GRB 240218A: NOEMA upper limit
  24. GRB 240229A: CALET Gamma-Ray Burst Monitor detection
  25. IceCube-240229A - IceCube observation of a high-energy neutrino candidate track-like event
  26. GRB 240225B: further SAO RAS optical observations
  27. Fermi GRB 240229A: Global MASTER-Net observations report
  28. GRB 240225B: Swift ToO observations
  29. Konus-Wind detection of GRB 240225B (long)
  30. GRB 240229A: BALROG localization (Fermi Trigger 730908432 / GRB 240229588)
  31. GRB 240229A: Fermi GBM Final Real-time Localization
  32. GRB 240225B: VLT/X-shooter redshift
  33. GRB 240225B : MITSuME Akeno optical afterglow candidate detection
  34. GRB 240225B: 3.6m DOT observation
  35. GRB 240225B: WINTER near-IR observations and upper limits
  36. GRB 240225B: SAO RAS optical observations
  37. GRB 240226A: GRBAlpha detection
  38. GRB 240225B: Mondy afterglow observations
  39. Fermi GRB 240227A: Global MASTER-Net observations report
  40. GRB 240225B: Liverpool Telescope afterglow observations
  41. Swift J1727.8-1613 (GRB 230824A): Madrona Peak Observatory - optical follow-up
  42. Swift Trigger 1217799 is not a GRB
  43. IPN triangulation of GRB 240227A (short)
  44. GRB 240225B: Liverpool Telescope optical afterglow observations
  45. GRB 240225B: NOT optical observations
  46. GRB 240218A: CMO SAI NIR upper limit
  47. Fermi GRB 240226A: Global MASTER-Net observations report
  48. GRB 240227A: Fermi GBM Final Real-time Localization
  49. Fermi Gamma-ray Burst Monitor trigger 730618809/240226236 is not a GRB
  50. GRB 240225B: Nanshan/HMT optical afterglow detection
  51. GRB 240225B: CALET Gamma-Ray Burst Monitor detection
  52. GRB 240225B: Swift-XRT observations
  53. GRB 240226B: Fermi GBM Final Real-time Localization
  54. GRB 240225C: CALET Gamma-Ray Burst Monitor detection
  55. GRB 240225B: GOTO detection of a candidate optical afterglow
  56. GRB 240226A: Fermi GBM Final Real-time Localization
  57. GRB 240225C: GRBAlpha detection
  58. GRB 240222A: ATCA radio observations
  59. Fermi trigger No 730618809: Global MASTER-Net observations report
  60. GRB 240225C: AstroSat CZTI detection
  61. GRB 240225B: AstroSat CZTI detection
  62. GRB 240225B: Tiled Swift observations
  63. GRB 240225B: MAXI/GSC detection
  64. Transient EPW20240219aa: Xinglong-2.16m optical upper limit
  65. GRB 240218A: VLA detection
  66. GRB 240225A: Swift/BAT-GUANO detection of a short burst
  67. GRB 240222A: GRBAlpha detection
  68. VLA X-band observation of EPW20240219aa
  69. Transient EPW20240219aa: Mondy optical observations
  70. Transient EPW20240219aa: upper limit in gamma-ray range from SPI-ACS/INTEGRAL observations
  71. Insight-HXMT/HE Sub-Threshold Detection of Transient EPW20240219aa
  72. Swift BAT Sub-Threshold Detection of EPW20240219aa
  73. GRB 240222A: GECAM detection of a burst
  74. GRB 240222A: Swift-BAT refined analysis
  75. GRB 240222A: Swift-XRT refined Analysis
  76. GRB 240222A: Fermi GBM Observation
  77. GRB 240222A: Swift/UVOT Upper Limits
  78. Fermi GBM Sub-Threshold Detection of EPW20240219aa as a likely GRB
  79. Swift GRB 240222A: Global MASTER-Net observations report
  80. Fermi GRB 240222A: Global MASTER-Net observations report
  81. EPW20240219aa is Likely a GRB Event
  82. GRB 240222A: REM optical and NIR early-time observations
  83. GRB 240222A: Swift detection of a burst
  84. GRB 240222A: Fermi GBM Final Real-time Localization
  85. GRB 240218A: MeerLICHT upper limits
  86. GRB 240216A: Glowbug gamma-ray detection
  87. GRB 240215B: Fermi GBM Observation
  88. GRB 240218A: LBT H-band detection
  89. GRB 240218A: Swift-BAT refined analysis
  90. Fermi GRB 240220A: Global MASTER-Net observations report
  91. GRB 240220A: Fermi GBM Final Real-time Localization
  92. Konus-Wind detection of GRB 240218A
  93. GRB 240218A: Swift-XRT refined Analysis
  94. GRB 240218A: VLT/X-shooter redshift of z = 6.782
  95. GRB 240218A: Fermi GBM Detection
  96. GRB 240215A: Fermi GBM Observation
  97. GRB 240216A: GRBAlpha detection
  98. GRB 240215B: GRBAlpha detection
  99. IPN triangulation of GRB 240209A
  100. Fermi trigger No 729914426: Global MASTER-Net observations report

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