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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"

24534 results found.

  1. IPN triangulation of GRB 240227A (short)
  2. GRB 240225B: Liverpool Telescope optical afterglow observations
  3. GRB 240225B: NOT optical observations
  4. Fermi GRB 240226A: Global MASTER-Net observations report
  5. GRB 240227A: Fermi GBM Final Real-time Localization
  6. GRB 240225B: Nanshan/HMT optical afterglow detection
  7. GRB 240225B: Swift-XRT observations
  8. GRB 240226B: Fermi GBM Final Real-time Localization
  9. Transient EPW20240219aa: J-band upper limits from WINTER
  10. GRB 240225B: GOTO detection of a candidate optical afterglow
  11. GRB 240226A: Fermi GBM Final Real-time Localization
  12. Transient EPW20240219aa: REM optical/NIR upper limits
  13. GRB 240225C: GRBAlpha detection
  14. Fermi trigger No 730618809: Global MASTER-Net observations report
  15. GRB 240225B: AstroSat CZTI detection
  16. GRB 240225A: Swift/BAT-GUANO detection of a short burst
  17. GRB 240222A: GRBAlpha detection
  18. Transient EPW20240219aa: GECKO: LOAO Optical Upper Limits
  19. Transient EPW20240219aa: 7DT Optical Upper Limits
  20. VLA X-band observation of EPW20240219aa
  21. Transient EPW20240219aa: upper limit in gamma-ray range from SPI-ACS/INTEGRAL observations
  22. Insight-HXMT/HE Sub-Threshold Detection of Transient EPW20240219aa
  23. GRB 240222A: GECAM detection of a burst
  24. GRB 240222A: Swift-BAT refined analysis
  25. GRB 240222A: Fermi GBM Observation
  26. Fermi GBM Sub-Threshold Detection of EPW20240219aa as a likely GRB
  27. Swift GRB 240222A: Global MASTER-Net observations report
  28. Fermi GRB 240222A: Global MASTER-Net observations report
  29. EPW20240219aa is Likely a GRB Event
  30. GRB 240222A: REM optical and NIR early-time observations
  31. GRB 240222A: Fermi GBM Final Real-time Localization
  32. Swift GRB240221.92: Global MASTER-Net observations report
  33. GRB 240218A: MeerLICHT upper limits
  34. GRB 240216A: Glowbug gamma-ray detection
  35. GRB 240215B: Fermi GBM Observation
  36. GRB 240218A: LBT H-band detection
  37. GRB 240218A: Swift-BAT refined analysis
  38. Fermi GRB 240220A: Global MASTER-Net observations report
  39. GRB 240220A: Fermi GBM Final Real-time Localization
  40. Konus-Wind detection of GRB 240218A
  41. GRB 240218A: VLT/X-shooter redshift of z = 6.782
  42. GRB 240218A: Fermi GBM Detection
  43. GRB 240215A: Fermi GBM Observation
  44. GRB 240216A: GRBAlpha detection
  45. GRB 240215B: GRBAlpha detection
  46. IPN triangulation of GRB 240209A
  47. Fermi trigger No 729914426: Global MASTER-Net observations report
  48. GRB 240218A: VLT/FORS2 z-band detection
  49. GRB 240218A: REM detection of a NIR afterglow candidate
  50. Gamma-ray flaring activity from the blazar 1ES 1959+650 observed by the Fermi-LAT
  51. GRB 240213A: GRBAlpha detection
  52. GRB 240218A : r-band upper limit from Observatoire de Haute-Provence
  53. Swift GRB240218.08: Global MASTER-Net observations report
  54. GRB 240215C: Fermi GBM Final Real-time Localization
  55. GRB 240215B: Swift/BAT-GUANO detection of a burst outside the coded FOV
  56. Fermi GRB 240216A: Global MASTER-Net observations report
  57. GRB 240216A: Fermi GBM Final Real-time Localization
  58. Fermi trigger No 729719508: Global MASTER-Net observations report
  59. GRB 240215A: Swift/BAT-GUANO localization of a burst
  60. Fermi trigger No 729703985: Global MASTER-Net observations report
  61. Fermi trigger No 729650855: Global MASTER-Net observations report
  62. GRB 240209A: Fermi GBM observation
  63. GRB 240128A: Further Swift-XRT observations
  64. GRB 240213A: BALROG localization (Fermi Trigger / GRB 240213841)
  65. Fermi GRB 240213A: Global MASTER-Net observations report
  66. GRB 240213A: Fermi GBM Final Real-time Localization
  67. GRB 240209A: NOT photometry of the AT2024cew / GOTO24pw counterpart candidate
  68. GRB 240209A: GOTO optical counterpart candidate
  69. Konus-Wind detection of GRB 240204A
  70. Konus-Wind detection of GRB 240205A (short)
  71. GRB 240209A: Fermi GBM Final Localization
  72. Fermi trigger No 729152364: Global MASTER-Net observations report
  73. IPN triangulation of GRB 240205A (short)
  74. Fermi-LAT gamma-ray observations of IceCube-240204A
  75. GRB 240205B: PRIME near infrared detection
  76. GRB 240205A (short): Glowbug gamma-ray detection
  77. Fermi trigger No 729012023: Global MASTER-Net observations report
  78. GRB 240205B: Swift-BAT refined analysis
  79. Konus-Wind detection of GRB 240205B (long / very soft)
  80. GRB 240207A: Fermi GBM Final Real-time Localization
  81. Konus-Wind detection of GRB 240125A
  82. GRB 240205B: VLT/X-shooter redshift
  83. GRB 240205B: CALET Gamma-Ray Burst Monitor detection
  84. GRB 240205B: ATCA detection of radio counterpart
  85. GRB 240205B: REM detection of the optical/NIR afterglow
  86. GRB 240205B: Fermi GBM Observation
  87. GRB 240205B: GECAM detection of a long burst
  88. GRB 240204A: Swift-BAT refined analysis
  89. GRB 240205B: Skynet Optical Afterglow Observations
  90. Fermi trigger No 728749569: Global MASTER-Net observations report
  91. GRB 240205B: MASTER OT J232550.14-550704.6 counterpart detection
  92. GRB 240205B: Fermi GBM Final Real-time Localization
  93. Swift GRB240205.93: Global MASTER-Net observations report
  94. GRB 240204A: Fermi GBM Observation
  95. GRB 240205A: Fermi GBM Final Real-time Localization
  96. GRB 240204a: Liverpool Telescope optical afterglow detection
  97. IceCube-240204A: Upper limits from a search for additional neutrino events in IceCube
  98. Fermi trigger No 728796365: Global MASTER-Net observations report
  99. GRB 240204A: Mondy optical afterglow candidate
  100. Fermi GRB 240204A: Global MASTER-Net observations report

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