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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"

27308 results found.

  1. GRB 230506B: MASTER optical observations
  2. GRB 230506B: Swift detection of a burst
  3. GRB 230506A: Fermi GBM Final Real-time Localization
  4. Fermi trigger No 704837952: Global MASTER-Net observations report
  5. GRB 230427A: Swift-BAT refined analysis
  6. GRB 230503A: Fermi GBM Final Real-time Localization
  7. IPN triangulation of GRB 230430A (short)
  8. GRB 230420A: AROMA-N Optical Upper Limit
  9. GRB 230430B: Fermi GBM Final Localization
  10. GRB 230430A: Fermi GBM observation
  11. GRB 230430A: Fermi GBM Final Real-time Localization
  12. GRB 230427A: NOT optical upper limit
  13. GRB 230427A: Swift/UVOT Detection
  14. GRB 230427A: Gaoyazi/GOT optical upper limit
  15. GRB 230427A: Nanshan/HMT optical upper limit
  16. GRB 230427A: Osservatorio Astronomico Nastro verde upper limit
  17. GRB 230427A: Swift-XRT refined Analysis
  18. Fermi trigger No 704365743: Global MASTER-Net observations report
  19. GRB 230428A: Fermi GBM Final Real-time Localization
  20. GRB 230427A: GIT optical upper limit
  21. GRB 230427A: Bassano Bresciano Observatory upper limit
  22. GRB 230427A: GMG upper limit
  23. GRB 230427A : OHP/T193 optical upper limit
  24. GRB 230427A: BOOTES-5/JGT afterglow detection
  25. GRB 230423A(trigger #1165354): Swift-BAT refined analysis
  26. GRB 230427A: AKO Upper Limit
  27. Swift GRB230427.44: Global MASTER-Net observations report
  28. GRB 230426A: MASTER OT J023135.16-792104.8 optical counterpart discovery
  29. GRB 230427A: MITSuME Akeno optical upper limits
  30. GRB 230426A: Fermi GBM Detection
  31. GRB 230427A: Swift detection of a burst with an optical counterpart
  32. Fermi trigger No 704233744: Global MASTER-Net observations report
  33. GRB 230426A: Fermi GBM Final Real-time Localization
  34. GRB 230423A: Swift/UVOT Upper Limits
  35. GRB 230425A: Fermi GBM Final Real-time Localization
  36. GRB 230423A: Swift-XRT refined Analysis
  37. GRB 230420A: Lowell Discovery Telescope Optical Detection
  38. GRB 230423A: Swift-XRT afterglow detection
  39. Swift Trigger 1165354 is probably not a GRB
  40. GRB 230421A: Fermi GBM observation
  41. GRB 230420A: Swift/UVOT Upper Limits
  42. GRB 230421: Swift/BAT-GUANO arcminute localization
  43. GRB230420A: VLT optical observation
  44. GRB 230420A: Swift-BAT refined analysis
  45. GRB 230421A: Fermi GBM Final Real-time Localization
  46. GRB 230420A: Swift-XRT refined Analysis
  47. GRB 230420A: NOT optical afterglow confirmation
  48. GRB 230420A: Gaoyazi/GOT optical upper limit
  49. GRB 230420A: BOOTES-5/JGT optical afterglow detection
  50. GRB 230420A: LCOGT Optical Upper Limit
  51. IPN triangulation of GRB 230418A (short)
  52. GRB 230420A: Swift detection of a burst
  53. GRB 230402A: Fermi GBM detection
  54. GRB 230419A: Fermi GBM Final Real-time Localization
  55. GRB 230418A: Swift/BAT-GUANO detection outside the coded FOV
  56. GRB 230418A: Fermi GBM Observation
  57. GRB 230402A: Fermi-LAT detection
  58. GRB 230414B Swift-BAT refined analysis
  59. GRB 230415A: Fermi GBM detection
  60. GRB 230414B: Swift/UVOT Detection
  61. GRB 230414B: Osservatorio Astronomico Nastro Verde - Sorrento: optical observations
  62. GRB 230415A: Swift/BAT-GUANO detection
  63. GRB 230414B: 3.6m DOT Optical observations, slow decay at early epochs
  64. GRB 230307A: iTelescope optical upper limit (likely)
  65. GRB 230414B: Montarrenti Observatory late time optical afterglow detection
  66. Fermi trigger No 703284533: Global MASTER-Net observations report
  67. GRB 230414B: Lulin 40cm-SLT optical limit
  68. GRB 230414B: Bassano Bresciano Observatory optical observations
  69. GRB 230409B: 3.6m DOT near-infrared detection, afterglow confirmation
  70. GRB 230414B: Swift-XRT refined Analysis
  71. GRB 230414B: Dabancheng/GHOST optical observations
  72. Fermi GRB 230414A: Global MASTER-Net observations report
  73. GRB 230414B: GROWTH India Telescope afterglow confirmation
  74. GRB 230414B: Nanshan/HMT optical afterglow detection
  75. Swift GRB 230414B: Global MASTER-Net observations report
  76. GRB 230414B: Swift detection of a burst
  77. GRB 230414A: Fermi GBM Final Real-time Localization
  78. GRB 230328B: redshift lower limit estimating
  79. GRB 230409B: OHP/T193 optical upper limit
  80. GRB 230410B: VZLUSAT-2 detection
  81. GRB 230409D: VZLUSAT-2 detection
  82. GRB 230410A: Fermi GBM Final Real-time Localization
  83. Fermi GRB 230409C: Global MASTER-Net observations report
  84. Fermi GRB 230409A: Global MASTER-Net observations report
  85. GRB 230409C: Fermi GBM Final Real-time Localization
  86. GRB 230409B: Swift-XRT refined Analysis
  87. GRB 230409B: Swift-BAT refined analysis
  88. Fermi trigger No 702745263: Global MASTER-Net observations report
  89. Swift GRB 230409B: Global MASTER-Net observations report
  90. GRB 230409B: Swift/UVOT Detection
  91. MAXI GRB230408.82: Global MASTER-Net observations report
  92. GRB 230409B: Swift detection of a burst
  93. GRB 230409A: Fermi GBM Final Real-time Localization
  94. GRB 230405B: Swift-XRT refined Analysis
  95. GRB 230405B: Fermi GBM Observation
  96. GRB 230405B: MeerLICHT upper limits
  97. IceCube Alert 230405.56: Global MASTER-Net observations report
  98. GRB 230405B: Swift/UVOT Upper Limits
  99. Swift GRB 230405B: Global MASTER-Net observations report
  100. GRB 230405B: Swift detection of a burst

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