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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"

36397 results found.

  1. GRB 240225C: CALET Gamma-Ray Burst Monitor detection
  2. GRB 240225B: GOTO detection of a candidate optical afterglow
  3. GRB 240226A: Fermi GBM Final Real-time Localization
  4. GRB 240225C: GRBAlpha detection
  5. GRB 240222A: ATCA radio observations
  6. GRB 240225C: AstroSat CZTI detection
  7. GRB 240225B: AstroSat CZTI detection
  8. GRB 240225B: Tiled Swift observations
  9. GRB 240225B: MAXI/GSC detection
  10. GRB 240218A: VLA detection
  11. GRB 240225A: Swift/BAT-GUANO detection of a short burst
  12. GRB 240222A: GRBAlpha detection
  13. VLA X-band observation of EPW20240219aa
  14. Transient EPW20240219aa: Mondy optical observations
  15. Transient EPW20240219aa: upper limit in gamma-ray range from SPI-ACS/INTEGRAL observations
  16. Swift BAT Sub-Threshold Detection of EPW20240219aa
  17. GRB 240222A: GECAM detection of a burst
  18. GRB 240222A: Swift-BAT refined analysis
  19. GRB 240222A: Swift-XRT refined Analysis
  20. GRB 240222A: Fermi GBM Observation
  21. GRB 240222A: Swift/UVOT Upper Limits
  22. Fermi GBM Sub-Threshold Detection of EPW20240219aa as a likely GRB
  23. Swift GRB 240222A: Global MASTER-Net observations report
  24. Fermi GRB 240222A: Global MASTER-Net observations report
  25. EPW20240219aa is Likely a GRB Event
  26. GRB 240222A: REM optical and NIR early-time observations
  27. GRB 240222A: Swift detection of a burst
  28. GRB 240222A: Fermi GBM Final Real-time Localization
  29. GRB 240218A: MeerLICHT upper limits
  30. GRB 240216A: Glowbug gamma-ray detection
  31. GRB 240215B: Fermi GBM Observation
  32. GRB 240218A: LBT H-band detection
  33. GRB 240218A: Swift-BAT refined analysis
  34. Fermi GRB 240220A: Global MASTER-Net observations report
  35. GRB 240220A: Fermi GBM Final Real-time Localization
  36. Konus-Wind detection of GRB 240218A
  37. GRB 240218A: Swift-XRT refined Analysis
  38. GRB 240218A: VLT/X-shooter redshift of z = 6.782
  39. GRB 240218A: Fermi GBM Detection
  40. GRB 240215A: Fermi GBM Observation
  41. GRB 240216A: GRBAlpha detection
  42. GRB 240215B: GRBAlpha detection
  43. IPN triangulation of GRB 240209A
  44. GRB 240218A: VLT/FORS2 z-band detection
  45. GRB 240218A: Enhanced Swift-XRT position
  46. GRB 240218A: REM detection of a NIR afterglow candidate
  47. GRB 240213A: GRBAlpha detection
  48. GRB 240218A : r-band upper limit from Observatoire de Haute-Provence
  49. GRB240218A: VLT/X-shooter upper limits
  50. GRB 240218A: Swift detection of a burst
  51. GRB 240215C: Fermi GBM Final Real-time Localization
  52. GRB 240215B: Swift/BAT-GUANO detection of a burst outside the coded FOV
  53. Fermi GRB 240216A: Global MASTER-Net observations report
  54. GRB 240216A: Fermi GBM Final Real-time Localization
  55. GRB 240215A: Tiled Swift observations
  56. GRB 240215A: Swift/BAT-GUANO localization of a burst
  57. GRB 240209A: Classification of AT2024cew/GOTO24pw as Type Ia-pec supernova
  58. GRB 240209A: Fermi GBM observation
  59. GRB 240213A: Glowbug gamma-ray detection
  60. GRB240209A: OHP/T193 detection of the GOTO afterglow candidate AT2024cew / GOTO24pw
  61. GRB 240209A: Wendelstein Optical Observations
  62. GRB 240128A: Further Swift-XRT observations
  63. GRB 240214A: Tiled Swift observations
  64. GRB 240214A/1H 0451-560: MAXI/GSC detection
  65. GRB 240213A: BALROG localization (Fermi Trigger / GRB 240213841)
  66. Fermi GRB 240213A: Global MASTER-Net observations report
  67. GRB 240213A: Fermi GBM Final Real-time Localization
  68. GRB 240209A: NOEMA non-detection of AT2024cew / GOTO24pw counterpart candidate
  69. GRB 240209A: NOT photometry of the AT2024cew / GOTO24pw counterpart candidate
  70. GRB 240209A: GOTO optical counterpart candidate
  71. Konus-Wind detection of GRB 240204A
  72. Konus-Wind detection of GRB 240205A (short)
  73. GRB 240209A: Fermi GBM Final Localization
  74. IPN triangulation of GRB 240205A (short)
  75. GRB 240205B: PRIME near infrared detection
  76. GRB 240205A (short): Glowbug gamma-ray detection
  77. GRB240204A: Swift/UVOT Upper Limits
  78. GRB 240205B: AstroSat CZTI detection
  79. GRB 240205B: Swift-BAT refined analysis
  80. Konus-Wind detection of GRB 240205B (long / very soft)
  81. GRB 240207A: Fermi GBM Final Real-time Localization
  82. Konus-Wind detection of GRB 240125A
  83. GRB 240205B: VLT/X-shooter redshift
  84. GRB 240205B: CALET Gamma-Ray Burst Monitor detection
  85. GRB 240205B: BOOTES-6 optical afterglow follow-up
  86. GRB 240205B: ATCA detection of radio counterpart
  87. GRB 240205B: REM detection of the optical/NIR afterglow
  88. GRB 240205B: Fermi GBM Observation
  89. GRB 240204A: AstroSat CZTI detection
  90. GRB 240204A: Mondy optical afterglow observations
  91. GRB 240204A : OHP/T193/T120 optical afterglow fading detection
  92. GRB 240205B: GECAM detection of a long burst
  93. GRB 240204A: Swift-BAT refined analysis
  94. GRB 240205B: Skynet Optical Afterglow Observations
  95. GRB 240205B: BOOTES-7 optical afterglow follow-up
  96. GRB 240205B: MASTER OT J232550.14-550704.6 counterpart detection
  97. GRB 240205B: Swift detection of a burst
  98. GRB 240205B: Fermi GBM Final Real-time Localization
  99. GRB 240204A: Fermi GBM Observation
  100. GRB 240205A: Fermi GBM Final Real-time Localization

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