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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"

37788 results found.

  1. IPN triangulation of GRB 240124B
  2. GRB 240201A: AstroSat CZTI detection
  3. GRB 240129A: Fermi GBM Observation
  4. IPN triangulation of GRB 240125B (short)
  5. GRB 240129A: Swift/BAT-GUANO detection of a burst outside the coded FOV
  6. IPN triangulation of GRB 240125A (short)
  7. GRB 240128A: Glowbug gamma-ray detection
  8. GRB 240128A: Swift-XRT observations
  9. GRB 240128A: GRBAlpha detection
  10. GRB 240128A: Tiled Swift observations
  11. GRB 240128A: CALET Gamma-Ray Burst Monitor detection
  12. GRB 240128A: MAXI/GSC detection
  13. GRB 240125A: GRBAlpha detection
  14. Fermi GRB 240127A: Global MASTER-Net observations report
  15. GRB 240123C: GRBAlpha detection
  16. GRB 240122A: ATCA detection of radio counterpart
  17. GRB 240127A: Fermi GBM Final Real-time Localization
  18. GRB 240125A: CALET Gamma-Ray Burst Monitor detection
  19. GRB 240125A: AstroSat CZTI detection of a short burst
  20. GRB 240124B: AstroSat CZTI detection
  21. GRB 240123C: AstroSat CZTI detection
  22. GRB 240125B: Fermi GBM Final Localization
  23. GRB 240123B: Fermi GBM Observation
  24. GRB 240123A: Glowbug gamma-ray detection
  25. GRB 240125A (short): Glowbug gamma-ray detection
  26. GRB 240123B: Swift/BAT-GUANO detection of a long burst
  27. GRB 240123A: GRBAlpha detection
  28. IPN triangulation of GRB 240123C (short)
  29. Fermi-LAT gamma-ray observations of IceCube-240123A
  30. GRB 240123A: further SAO RAS optical observations
  31. GRB 240122B: CALET Gamma-Ray Burst Monitor detection
  32. GRB 240123A: Swift-BAT refined analysis
  33. GRB 240123A: Mondy continued optical observations and the PL decay index
  34. GRB 240123A: SAO RAS optical observations
  35. GRB 240123A : MITSuME Akeno optical afterglow candidate detection
  36. Fermi/GBM trigger 727752941: BALROG analysis retraction
  37. GRB 240123A: Enhanced Swift-XRT position
  38. GRB 240124A?: BALROG localization (Fermi Trigger 727752941 / GRB 240124066)
  39. Fermi GRB 240123B: Global MASTER-Net observations report
  40. GRB 240122A: Swift/UVOT Upper Limits
  41. GRB 240123A: Swift-XRT refined Analysis
  42. GRB 240122A: BOOTES-2/TELMA optical upper limit and 1.5m OSN detection
  43. Fermi GBM Sub-Threshold Detection of GRB 240123A
  44. GRB 240123A: Mondy continued optical observations + correction of the GRB name in GCN 35605
  45. GRB 240123B: Fermi GBM Final Real-time Localization
  46. GRB 240118A: Swift/UVOT Upper Limits
  47. GRB 240122B: Glowbug gamma-ray detection
  48. GRB 240123A: Mondy optical afterglow observations
  49. IceCube-240123A - IceCube observation of a high-energy neutrino candidate track-like event
  50. Konus-Wind detection of GRB 240112A
  51. GRB 240123A: Swift detection of a burst with a possible optical counterpart
  52. GRB 240122A: Swift-XRT afterglow detection
  53. GRB 240122A: VLT/X-shooter redshift confirmation
  54. GRB 240122A: Redshift from OSIRIS+/GTC
  55. GRB 240122A: LT non-detection of GOTO candidate counterpart confirms fading
  56. GRB 240122A: GOTO optical counterpart candidate
  57. GRB 240122A: Tiled Swift observations
  58. Konus-Wind detection of GRB 240119A (short/hard)
  59. GRB 240122A: MAXI/GSC detection
  60. IPN triangulation of GRB 240119A (short)
  61. GRB 240119A: GECAM detection of a short burst
  62. GRB 240118C: GECAM-B detection of a long burst
  63. GRB 240119A: AstroSat CZTI detection of a short burst
  64. GRB 240118A: Mondy optical observations
  65. GRB 240118A: Swift-XRT afterglow detection
  66. GRB 240118C: Fermi GBM Observation
  67. Fermi GRB 240119A: Global MASTER-Net observations report
  68. GRB 240119A: Fermi GBM Final Localization
  69. GRB 240117A: CALET Gamma-Ray Burst Monitor detection
  70. GRB 240118C: Swift/BAT-GUANO detection of a burst
  71. GRB 240118A: GRBAlpha detection
  72. GRB 240115A: Fermi GBM Observation
  73. GRB 240118C: Fermi GBM Final Localization
  74. GRB 240118D: AstroSat CZTI detection
  75. GRB 240117A: AstroSat CZTI detection
  76. GRB 240118A: Swift ToO observations
  77. GRB 240118A: AbAO optical upper limit
  78. Fermi GRB 240118B: Global MASTER-Net observations report
  79. GRB 240118A: NuSTAR Offline Analysis of the GRB
  80. GRB 240117A: Glowbug gamma-ray detection
  81. GRB 240118A: Swift/BAT-GUANO detection of a burst outside the coded FOV
  82. Konus-Wind detection of GRB 240118A
  83. GRB 240118C: BALROG localization (Fermi Trigger 727291408 / GRB 240118725)
  84. GRB 240118A: NuSTAR Detection of a Long GRB
  85. GRB 240118A: Fermi GBM Observation
  86. GRB 240118B: Fermi GBM Final Real-time Localization
  87. GRB 240118A: Fermi-LAT detection
  88. GRID detection of GRB 231230A
  89. GRB 240118A: Fermi GBM Final Real-time Localization
  90. GRB 240115A: Swift/BAT-GUANO detection of a short burst
  91. IPN triangulation of GRB 240112A (long)
  92. GRB 240115B: AstroSat CZTI detection
  93. LIGO/Virgo/KAGRA S240109a: Upper limits from Swift/BAT-GUANO
  94. GRB 240115B: Fermi GBM Detection
  95. GRB 240112D: Glowbug gamma-ray detection
  96. GRB 240112C: Glowbug gamma-ray detection
  97. GRB 240112C: VZLUSAT-2 detection
  98. GRB 240107A: VZLUSAT-2 detection
  99. Fermi GRB 240115B: Global MASTER-Net observations report
  100. GRB 240115B: A long GRB detected by INTEGRAL

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