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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"

36145 results found.

  1. GRB 240209A: NOEMA non-detection of AT2024cew / GOTO24pw counterpart candidate
  2. GRB 240209A: NOT photometry of the AT2024cew / GOTO24pw counterpart candidate
  3. GRB 240209A: GOTO optical counterpart candidate
  4. Konus-Wind detection of GRB 240204A
  5. Konus-Wind detection of GRB 240205A (short)
  6. GRB 240209A: Fermi GBM Final Localization
  7. IPN triangulation of GRB 240205A (short)
  8. GRB 240205B: PRIME near infrared detection
  9. GRB 240205A (short): Glowbug gamma-ray detection
  10. GRB240204A: Swift/UVOT Upper Limits
  11. GRB 240205B: AstroSat CZTI detection
  12. GRB 240205B: Swift-BAT refined analysis
  13. Konus-Wind detection of GRB 240205B (long / very soft)
  14. GRB 240207A: Fermi GBM Final Real-time Localization
  15. Konus-Wind detection of GRB 240125A
  16. GRB 240205B: VLT/X-shooter redshift
  17. GRB 240205B: CALET Gamma-Ray Burst Monitor detection
  18. GRB 240205B: BOOTES-6 optical afterglow follow-up
  19. GRB 240205B: ATCA detection of radio counterpart
  20. GRB 240205B: REM detection of the optical/NIR afterglow
  21. GRB 240205B: Fermi GBM Observation
  22. GRB 240204A: AstroSat CZTI detection
  23. GRB 240204A: Mondy optical afterglow observations
  24. GRB 240204A : OHP/T193/T120 optical afterglow fading detection
  25. GRB 240205B: GECAM detection of a long burst
  26. GRB 240204A: Swift-BAT refined analysis
  27. GRB 240205B: Skynet Optical Afterglow Observations
  28. GRB 240205B: BOOTES-7 optical afterglow follow-up
  29. GRB 240205B: MASTER OT J232550.14-550704.6 counterpart detection
  30. GRB 240205B: Swift detection of a burst
  31. GRB 240205B: Fermi GBM Final Real-time Localization
  32. GRB 240204A: Fermi GBM Observation
  33. GRB 240205A: Fermi GBM Final Real-time Localization
  34. GRB 240204a: Liverpool Telescope optical afterglow detection
  35. GRB 240204A: Osservatorio Astronomico Nastro Verde upper limit
  36. Fermi Gamma-ray Burst Monitor trigger 728740048/240204491 is not a GRB
  37. GRB 240204A: optical afterglow detection with LCOGT 1m telescopes at Sutherland and Teide Observatories
  38. GRB 240204A: Montarrenti Observatory optical observations
  39. GRB 240204A: Enhanced Swift-XRT position
  40. GRB 240204A: Mondy optical afterglow candidate
  41. Fermi Gamma-ray Burst Monitor trigger 728706420/240204102 is not a GRB
  42. Fermi GRB 240204A: Global MASTER-Net observations report
  43. GRB 240204A: Swift detection of a burst
  44. GRB 240204A: Fermi GBM Final Real-time Localization
  45. GRB 230812B: Update on Bad Time Intervals for Fermi GBM data
  46. Konus-Wind detection of GRB 240124B
  47. Konus-Wind detection of GRB 240123C
  48. IPN triangulation of GRB 240124B
  49. GRB 240201A: AstroSat CZTI detection
  50. GRB 240129A: Fermi GBM Observation
  51. IPN triangulation of GRB 240125B (short)
  52. GRB 240129A: Swift/BAT-GUANO detection of a burst outside the coded FOV
  53. IPN triangulation of GRB 240125A (short)
  54. GRB 240128A: Glowbug gamma-ray detection
  55. GRB 240128A: Swift-XRT observations
  56. GRB 240128A: GRBAlpha detection
  57. GRB 240128A: Tiled Swift observations
  58. GRB 240128A: CALET Gamma-Ray Burst Monitor detection
  59. GRB 240128A: MAXI/GSC detection
  60. GRB 240125A: GRBAlpha detection
  61. Fermi GRB 240127A: Global MASTER-Net observations report
  62. GRB 240123C: GRBAlpha detection
  63. GRB 240122A: ATCA detection of radio counterpart
  64. GRB 240127A: Fermi GBM Final Real-time Localization
  65. GRB 240125A: CALET Gamma-Ray Burst Monitor detection
  66. GRB 240125A: AstroSat CZTI detection of a short burst
  67. GRB 240124B: AstroSat CZTI detection
  68. GRB 240123C: AstroSat CZTI detection
  69. GRB 240125B: Fermi GBM Final Localization
  70. GRB240122A: PRIME near infrared detection
  71. GRB 240123B: Fermi GBM Observation
  72. GRB 240123A: Glowbug gamma-ray detection
  73. GRB 240125A (short): Glowbug gamma-ray detection
  74. GRB 240123B: Swift/BAT-GUANO detection of a long burst
  75. GRB 240123A: GRBAlpha detection
  76. IPN triangulation of GRB 240123C (short)
  77. GRB 240123A: further SAO RAS optical observations
  78. GRB 240122B: CALET Gamma-Ray Burst Monitor detection
  79. GRB 240123A: Swift-BAT refined analysis
  80. GRB 240123A: Mondy continued optical observations and the PL decay index
  81. GRB 240123A: SAO RAS optical observations
  82. GRB 240123A : MITSuME Akeno optical afterglow candidate detection
  83. Fermi/GBM trigger 727752941: BALROG analysis retraction
  84. GRB 240123A: Enhanced Swift-XRT position
  85. GRB 240124A?: BALROG localization (Fermi Trigger 727752941 / GRB 240124066)
  86. Fermi GRB 240123B: Global MASTER-Net observations report
  87. GRB 240122A: Swift/UVOT Upper Limits
  88. GRB 240123A: Swift-XRT refined Analysis
  89. GRB 240122A: BOOTES-2/TELMA optical upper limit and 1.5m OSN detection
  90. Fermi GBM Sub-Threshold Detection of GRB 240123A
  91. GRB 240123A: Mondy continued optical observations + correction of the GRB name in GCN 35605
  92. GRB 240123B: Fermi GBM Final Real-time Localization
  93. GRB 240118A: Swift/UVOT Upper Limits
  94. GRB 240122B: Glowbug gamma-ray detection
  95. GRB 240123A: Mondy optical afterglow observations
  96. Konus-Wind detection of GRB 240112A
  97. GRB 240123A: Swift detection of a burst with a possible optical counterpart
  98. GRB 240122A: Swift-XRT afterglow detection
  99. GRB 240122A: VLT/X-shooter redshift confirmation
  100. GRB 240122A: Redshift from OSIRIS+/GTC

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