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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"

39398 results found.

  1. GRB 230427A: Swift-BAT refined analysis
  2. GRB 230503A: Fermi GBM Final Real-time Localization
  3. Konus-Wind detection of GRB 230430A
  4. IPN triangulation of GRB 230430A (short)
  5. GRB 230420A: AROMA-N Optical Upper Limit
  6. GRB 230430B: Fermi GBM Final Localization
  7. GRB 230430A: Fermi GBM observation
  8. GRB 230430A: AstroSat CZTI detection
  9. GRB 230430A: Fermi GBM Final Real-time Localization
  10. GRB 230427A: NOT optical upper limit
  11. GRB 230427A: TSHAO, SAO RAS, AbAO optical upper limit
  12. GRB 230427A: Swift/UVOT Detection
  13. GRB 230427A: Gaoyazi/GOT optical upper limit
  14. GRB 230427A: OHP/T193 spectroscopy observations of WISEA J101316.01+481158.7
  15. GRB 230427A: Nanshan/HMT optical upper limit
  16. GRB 230427A: Osservatorio Astronomico Nastro verde upper limit
  17. GRB 230427A: OSIRIS+/GTC observations
  18. GRB 230427A: Swift-XRT refined Analysis
  19. GRB 230426A: VZLUSAT-2 detection
  20. Fermi trigger No 704365743: Global MASTER-Net observations report
  21. GRB 230428A: Fermi GBM Final Real-time Localization
  22. GRB 230427A: GIT optical upper limit
  23. GRB 230427A: Bassano Bresciano Observatory upper limit
  24. GRB 230427A: GMG upper limit
  25. GRB 230427A : OHP/T193 optical upper limit
  26. GRB 230427A: BOOTES-5/JGT afterglow detection
  27. GRB 230423A(trigger #1165354): Swift-BAT refined analysis
  28. GRB 230427A: AKO Upper Limit
  29. Swift GRB230427.44: Global MASTER-Net observations report
  30. GRB 230426A: MASTER OT J023135.16-792104.8 optical counterpart discovery
  31. GRB 230427A: MITSuME Akeno optical upper limits
  32. GRB 230426A: Fermi GBM Detection
  33. GRB 230427A: Enhanced Swift-XRT position
  34. GRB 230427A: Swift detection of a burst with an optical counterpart
  35. GRB 230426A: AstroSat CZTI detection
  36. Fermi trigger No 704233744: Global MASTER-Net observations report
  37. GRB 230426A: Fermi GBM Final Real-time Localization
  38. GRB 230423A: Swift/UVOT Upper Limits
  39. GRB 230425A: Fermi GBM Final Real-time Localization
  40. GRB 230423A: Swift-XRT refined Analysis
  41. GRB 230420A: Lowell Discovery Telescope Optical Detection
  42. GRB 230423A: Swift-XRT afterglow detection
  43. Swift Trigger 1165354 is probably not a GRB
  44. GRB 221009A: Late-time JWST Observations and Detection of Supernova Emission
  45. GRB 230421A: Fermi GBM observation
  46. Konus-Wind detection of GRB 230418A
  47. GRB 230420A: Swift/UVOT Upper Limits
  48. GRB 230421: Swift/BAT-GUANO arcminute localization
  49. GRB230420A: VLT optical observation
  50. GRB 230420A: Swift-BAT refined analysis
  51. GRB 230421A: Fermi GBM Final Real-time Localization
  52. GRB 230420A: Swift-XRT refined Analysis
  53. GRB 230420A: MITSuME Akeno optical observation
  54. GRB 230420A: NOT optical afterglow confirmation
  55. GRB 230420A: Gaoyazi/GOT optical upper limit
  56. GRB 230420A: BOOTES-5/JGT optical afterglow detection
  57. GRB 230420A: LCOGT Optical Upper Limit
  58. GRB 230420A: Enhanced Swift-XRT position
  59. IPN triangulation of GRB 230418A (short)
  60. GRB 230420A: Swift detection of a burst
  61. GRB 230418A: AstroSat CZTI detection
  62. GRB 230418A: AGILE detection
  63. GRB 230402A: Fermi GBM detection
  64. GRB 230419A: Fermi GBM Final Real-time Localization
  65. GRB 230418A: Swift/BAT-GUANO detection outside the coded FOV
  66. GRB 230418A: Fermi GBM Observation
  67. GRB 230402A: Fermi-LAT detection
  68. Fermi-LAT gamma-ray observations of IceCube-230416A
  69. GRB 230414B: Nickel and KAIT telescope optical observations
  70. GRB 230414B Swift-BAT refined analysis
  71. GRB 230415A: Fermi GBM detection
  72. GRB 230414B: Swift/UVOT Detection
  73. GRB 230414B: Osservatorio Astronomico Nastro Verde - Sorrento: optical observations
  74. GRB 230415A: Swift/BAT-GUANO detection
  75. GRB 230414B: 3.6m DOT Optical observations, slow decay at early epochs
  76. GRB 230307A: iTelescope optical upper limit (likely)
  77. GRB 230414B: Montarrenti Observatory late time optical afterglow detection
  78. IceCube-230416A: IceCube observation of a high-energy neutrino candidate
  79. Fermi trigger No 703284533: Global MASTER-Net observations report
  80. GRB 230414B: Lulin 40cm-SLT optical limit
  81. GRB 230414B: Bassano Bresciano Observatory optical observations
  82. GRB 230414B: Redshift from OSIRIS/GTC
  83. GRB 230414B: AbAO optical observations
  84. GRB 230409B: 3.6m DOT near-infrared detection, afterglow confirmation
  85. GRB 230414B: Swift-XRT refined Analysis
  86. GRB 230414B: Dabancheng/GHOST optical observations
  87. GRB 230414B: slow optical light curve decay
  88. GRB 230414B: SAO RAS optical observations
  89. GRB 230414B: Enhanced Swift-XRT position
  90. GRB 230414B: 1.3m DFOT Optical observations
  91. Fermi GRB 230414A: Global MASTER-Net observations report
  92. GRB 230414B: GROWTH India Telescope afterglow confirmation
  93. GRB 230414B (correction GRB name in the GCN 33615): Mondy optical afterglow candidate
  94. GRB 230414B: Nanshan/HMT optical afterglow detection
  95. GRB 230414A: Mondy optical afterglow candidate
  96. Swift GRB 230414B: Global MASTER-Net observations report
  97. GRB 230414B: Prompt enhanced Swift-XRT position
  98. GRB 230414B: Swift detection of a burst
  99. IceCube-230405A: BOOTES-4/MET Optical Upper Limits
  100. GRB 230414A: Fermi GBM Final Real-time Localization

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