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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"

26124 results found.

  1. GRB 240204A: Mondy optical afterglow observations
  2. GRB 240204A : OHP/T193/T120 optical afterglow fading detection
  3. GRB 240205B: GECAM detection of a long burst
  4. GRB 240204A: Swift-BAT refined analysis
  5. GRB 240205B: Skynet Optical Afterglow Observations
  6. GRB 240205B: BOOTES-7 optical afterglow follow-up
  7. GRB 240205B: MASTER OT J232550.14-550704.6 counterpart detection
  8. GRB 240205B: Swift detection of a burst
  9. Swift GRB240205.93: Global MASTER-Net observations report
  10. GRB 240204A: Fermi GBM Observation
  11. GRB 240204a: Liverpool Telescope optical afterglow detection
  12. GRB 240204A: Osservatorio Astronomico Nastro Verde upper limit
  13. GRB 240204A: optical afterglow detection with LCOGT 1m telescopes at Sutherland and Teide Observatories
  14. GRB 240204A: Montarrenti Observatory optical observations
  15. GRB 240204A: Enhanced Swift-XRT position
  16. GRB 240204A: Mondy optical afterglow candidate
  17. GRB 240204A: Swift detection of a burst
  18. Swift Trigger 1212791 is not an astrophysical event.
  19. Swift-BAT triggers 1212787, 1212789 are not astrophysical.
  20. IPN triangulation of GRB 240124B
  21. GRB 240129A: Fermi GBM Observation
  22. GRB 240129A: Swift/BAT-GUANO detection of a burst outside the coded FOV
  23. IPN triangulation of GRB 240125A (short)
  24. GRB 240128A: Swift-XRT observations
  25. GRB 240128A: Tiled Swift observations
  26. GRB 240122A: ATCA detection of radio counterpart
  27. Swift Trigger 1211211 and 1211212 are not astrophysical
  28. GRB 240123C: AstroSat CZTI detection
  29. GRB240122A: PRIME near infrared detection
  30. GRB 240123B: Fermi GBM Observation
  31. GRB 240123A: Glowbug gamma-ray detection
  32. GRB 240123B: Swift/BAT-GUANO detection of a long burst
  33. GRB 240123A: GRBAlpha detection
  34. IPN triangulation of GRB 240123C (short)
  35. Swift trigger 1210856 is not astrophysical
  36. GRB 240123A: Swift-BAT refined analysis
  37. GRB 240123A: Mondy continued optical observations and the PL decay index
  38. GRB 240123A : MITSuME Akeno optical afterglow candidate detection
  39. GRB 240123A: Enhanced Swift-XRT position
  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 240118A: Swift/UVOT Upper Limits
  46. GRB 240123A: Mondy optical afterglow observations
  47. GRB 240123A: Swift detection of a burst with a possible optical counterpart
  48. Swift GRB240123.46: Global MASTER-Net observations report
  49. GRB 240122A: Swift-XRT afterglow detection
  50. GRB 240122A: Redshift from OSIRIS+/GTC
  51. GRB 240122A: Tiled Swift observations
  52. IPN triangulation of GRB 240119A (short)
  53. GRB 240118C: GECAM-B detection of a long burst
  54. GRB 240118A: Mondy optical observations
  55. GRB 240118A: Swift-XRT afterglow detection
  56. GRB 240118C: Fermi GBM Observation
  57. GRB 240118C: Swift/BAT-GUANO detection of a burst
  58. GRB 240118A: GRBAlpha detection
  59. GRB 240115A: Fermi GBM Observation
  60. Swift triggers 1209631, 1209632, 1209635 and 1209644 are not interesting astrophysical events
  61. GRB 240118A: Swift ToO observations
  62. GRB 240118A: AbAO optical upper limit
  63. GRB 240118A: NuSTAR Offline Analysis of the GRB
  64. GRB 240118A: Swift/BAT-GUANO detection of a burst outside the coded FOV
  65. GRB 240118A: Fermi-LAT detection
  66. GRID detection of GRB 231230A
  67. GRB 240115A: Swift/BAT-GUANO detection of a short burst
  68. Swift Trigger 1209406 is not an astrophysical event
  69. Swift Triggers 1209401 and 1209403 are not astrophysical events
  70. Swift Triggers 1209371 through 1209374 are not astrophysical events
  71. Swift Triggers 1209369 and 1209370 are not astrophysical events
  72. LIGO/Virgo/KAGRA S240109a: Upper limits from Swift/BAT-GUANO
  73. GRB 240112C: Glowbug gamma-ray detection
  74. GRB 240112C: VZLUSAT-2 detection
  75. Konus-Wind detection of GRB 240112C
  76. GRB 240112C: GRBAlpha detection
  77. GRB 240112C: Swift/UVOT Detection
  78. GRB 240112C: Fermi GBM Detection
  79. GRB 240112C: Swift-XRT refined Analysis
  80. GRB 240112C: SAO RAS optical observations
  81. Swift GRB 240112C: Global MASTER-Net observations report
  82. GRB 240109A: Swift-BAT refined analysis
  83. GRB 240112C: Swift detection of a burst with an optical counterpart
  84. GRB 240109A: Fermi GBM Observation
  85. GRB 231214A: ATCA Radio Upper Limits
  86. Konus-Wind detection of GRB 240101C
  87. Swift GRB240109.17: Global MASTER-Net observations report
  88. GRB 240109A: Swift detection of a short burst
  89. LIGO/Virgo/KAGRA S240104bl: Upper limits from Swift/BAT-GUANO
  90. IPN triangulation of GRB 240101C (short)
  91. GRB GRB240101C: Fermi GBM observation
  92. GRB 240101A: 1.3m DFOT optical observations
  93. GRB 240102A: 1.3m DFOT optical upper limit
  94. GRB 240101B: 1.3m DFOT optical upper limit
  95. GRB 240101C: Swift/BAT-GUANO detection of a short burst
  96. GRB 231220A: Swift-UVOT upper limit
  97. GRB 240102A: Swift-BAT refined analysis
  98. GRB 240102A: Swift/UVOT Upper Limits
  99. GRB 231230A: Swift-BAT refined analysis
  100. GRB 240101A: Swift-BAT refined analysis

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