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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"

28255 results found.

  1. GRB 230506C: TSHAO possible afterglow candidate
  2. GRB 230506B: Swift/UVOT Detection
  3. IceCube-230506A: IceCube observation of a high-energy neutrino candidate
  4. GRB 230506C: Swift detection of a burst
  5. GRB 230506B: Swift detection of a burst
  6. GRB 230506B: Swift detection of a burst
  7. GRB 230506A: Fermi GBM Final Real-time Localization
  8. GRB 230420A: Mondy optical afterglow detection, TSHAO, CrAO optical upper limit
  9. GRB 230430A: A short GRB from a neutron star merger
  10. GRB 230503A: Fermi GBM Final Real-time Localization
  11. Konus-Wind detection of GRB 230430A
  12. IPN triangulation of GRB 230430A (short)
  13. GRB 230420A: AROMA-N Optical Upper Limit
  14. GRB 230430B: Fermi GBM Final Localization
  15. GRB 230430A: AstroSat CZTI detection
  16. GRB 230430A: Fermi GBM Final Real-time Localization
  17. GRB 230427A: Swift/UVOT Detection
  18. GRB 230427A: OSIRIS+/GTC observations
  19. GRB 230427A: Swift-XRT refined Analysis
  20. GRB 230426A: VZLUSAT-2 detection
  21. GRB 230428A: Fermi GBM Final Real-time Localization
  22. GRB 230427A: GMG upper limit
  23. GRB 230427A : OHP/T193 optical upper limit
  24. GRB 230427A: BOOTES-5/JGT afterglow detection
  25. GRB 230427A: AKO Upper Limit
  26. GRB 230426A: MASTER OT J023135.16-792104.8 optical counterpart discovery
  27. GRB 230426A: Fermi GBM Detection
  28. GRB 230427A: Enhanced Swift-XRT position
  29. GRB 230427A: Swift detection of a burst with an optical counterpart
  30. GRB 230426A: AstroSat CZTI detection
  31. GRB 230426A: Fermi GBM Final Real-time Localization
  32. GRB 230423A: Swift/UVOT Upper Limits
  33. GRB 230425A: Fermi GBM Final Real-time Localization
  34. GRB 230423A: Swift-XRT refined Analysis
  35. GRB 230420A: Lowell Discovery Telescope Optical Detection
  36. GRB 230423A: Swift-XRT afterglow detection
  37. Swift Trigger 1165354 is probably not a GRB
  38. GRB 221009A: Late-time JWST Observations and Detection of Supernova Emission
  39. Konus-Wind detection of GRB 230418A
  40. GRB 230420A: Swift/UVOT Upper Limits
  41. GRB 230421: Swift/BAT-GUANO arcminute localization
  42. GRB230420A: VLT optical observation
  43. GRB 230421A: Fermi GBM Final Real-time Localization
  44. GRB 230420A: Swift-XRT refined Analysis
  45. GRB 230420A: MITSuME Akeno optical observation
  46. GRB 230420A: NOT optical afterglow confirmation
  47. GRB 230420A: Gaoyazi/GOT optical upper limit
  48. GRB 230420A: BOOTES-5/JGT optical afterglow detection
  49. GRB 230420A: LCOGT Optical Upper Limit
  50. GRB 230420A: Enhanced Swift-XRT position
  51. IPN triangulation of GRB 230418A (short)
  52. GRB 230420A: Swift detection of a burst
  53. GRB 230418A: AstroSat CZTI detection
  54. GRB 230418A: AGILE detection
  55. GRB 230402A: Fermi GBM detection
  56. GRB 230419A: Fermi GBM Final Real-time Localization
  57. GRB 230418A: Swift/BAT-GUANO detection outside the coded FOV
  58. GRB 230402A: Fermi-LAT detection
  59. GRB 230414B: Nickel and KAIT telescope optical observations
  60. GRB 230415A: Fermi GBM detection
  61. GRB 230414B: Swift/UVOT Detection
  62. GRB 230414B: Osservatorio Astronomico Nastro Verde - Sorrento: optical observations
  63. GRB 230415A: Swift/BAT-GUANO detection
  64. VIRT optical transient detection
  65. GRB 230414B: 3.6m DOT Optical observations, slow decay at early epochs
  66. GRB 230307A: iTelescope optical upper limit (likely)
  67. GRB 230414B: Montarrenti Observatory late time optical afterglow detection
  68. IceCube-230416A: IceCube observation of a high-energy neutrino candidate
  69. GRB 230414B: Lulin 40cm-SLT optical limit
  70. GRB 230414B: Bassano Bresciano Observatory optical observations
  71. GRB 230414B: Redshift from OSIRIS/GTC
  72. GRB 230414B: AbAO optical observations
  73. GRB 230409B: 3.6m DOT near-infrared detection, afterglow confirmation
  74. GRB 230414B: Swift-XRT refined Analysis
  75. GRB 230414B: Dabancheng/GHOST optical observations
  76. GRB 230414B: slow optical light curve decay
  77. GRB 230414B: Enhanced Swift-XRT position
  78. GRB 230414B: 1.3m DFOT Optical observations
  79. GRB 230414B: GROWTH India Telescope afterglow confirmation
  80. GRB 230414B (correction GRB name in the GCN 33615): Mondy optical afterglow candidate
  81. GRB 230414B: Nanshan/HMT optical afterglow detection
  82. GRB 230414A: Mondy optical afterglow candidate
  83. GRB 230414B: Prompt enhanced Swift-XRT position
  84. GRB 230414B: Swift detection of a burst
  85. GRB 230414A: Fermi GBM Final Real-time Localization
  86. GRB 230409B: Mondy optical upper limit
  87. GRB 230410B: VZLUSAT-2 detection
  88. GRB 230409D: VZLUSAT-2 detection
  89. GRB 230410B: AGILE detection of a burst
  90. GRB 230410A: Fermi GBM Final Real-time Localization
  91. GRB 230409C: Fermi GBM Final Real-time Localization
  92. GRB 230409B: Swift-XRT refined Analysis
  93. GRB 230409B: Swift/UVOT Detection
  94. GRB 230409B: Enhanced Swift-XRT position
  95. GRB 230409B: Swift detection of a burst
  96. GRB 230409A: Fermi GBM Final Real-time Localization
  97. GRB 230405B: VZLUSAT-2 detection
  98. Konus-Wind detection of GRB 230405B
  99. GRB 230405B: AGILE detection
  100. GRB 230405B: Swift-XRT refined Analysis

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