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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"

36184 results found.

  1. GRB 210826A: Tiled Swift observations
  2. GRB 210824A: MITSuME Akeno optical upper limits
  3. GRB 210826A: BALROG localization (Fermi Trigger 651654110 / GRB 210826293)
  4. GRB 210826A: Fermi GBM Final Real-time Localization
  5. GRB 210822A: TSHAO continued optical observation
  6. GRB 210822A: VLA detection
  7. GRB 210822A: TSHAO optical observation
  8. GRB 210822A: Swift/UVOT Detection
  9. Swift GRB 210824A: Global MASTER-Net observations report
  10. GRB 210824A: BOOTES-5/JGT optical upper limit
  11. GRB 210824A: Fermi GBM Observation
  12. Fermi GRB 210824A: Global MASTER-Net observations report
  13. GRB 210824A: Nanshan/NEXT optical upper limit
  14. GRB 210824A: Swift-XRT refined Analysis
  15. GRB 210822A: GROND observations
  16. GRB 210824A: Enhanced Swift-XRT position
  17. GRB 210822A: Abbey Ridge Observatory optical afterglow observation
  18. GRB 210824A: Swift detection of a burst
  19. GRB 210824A: Fermi GBM Final Real-time Localization
  20. GRB 210822B: DDOTI Upper Limits on the Afterglow
  21. GRB 210822A: Detection by GRBAlpha
  22. GRB 210822A: GECAM refined analysis
  23. GRB 210820A: GROND observations
  24. Konus-Wind detection of GRB 210822A
  25. GRB 210822A: AstroSat CZTI detection
  26. GRB 210822A: NOT photometry and spectroscopy
  27. GRB 210822A: Swift-XRT refined Analysis
  28. GRB 210822A: Swift-BAT refined analysis
  29. GRB 210820A: NUTTelA-TAO / BSTI Early Optical Limits (Preliminary)
  30. GRB 210822A: Fermi-LAT detection
  31. GRB 210820A: Swift/UVOT Detection
  32. Fermi GRB 210822B: Global MASTER-Net observations report
  33. GRB 210822A: Nanshan/NEXT optical observations
  34. GRB 210822B: Fermi GBM Final Real-time Localization
  35. GRB 210822A: Enhanced Swift-XRT position
  36. Swift GRB 210822A: Global MASTER-Net observations report
  37. GRB 210822A: RATIR Optical Detections
  38. GRB 210822A: KAIT Optical Afterglow Confirmation
  39. GRB 210822A: GECAM detection
  40. GRB 210822A: Swift detection of a burst with an optical afterglow
  41. Fermi GRB 210821A: Global MASTER-Net observations report
  42. GRB 210820A: Swift-BAT refined analysis
  43. GRB 210820A: LT optical upper limit
  44. GRB 210820A: LCO Optical Upper Limit
  45. GRB 210820A: RATIR Optical Detections
  46. GRB 210821A: Fermi GBM Final Real-time Localization
  47. GRB 210820A: NOT optical upper limit
  48. GRB 210820A: Nanshan/NEXT optical upper limit
  49. GRB 210820A: Swift-XRT refined Analysis
  50. GRB 210820A: Enhanced Swift-XRT position
  51. Swift GRB 210820A: Global MASTER-Net observations report
  52. GRB 210820B: Fermi GBM Final Localization
  53. GRB 210820A: Swift detection of a burst with an optical counterpart
  54. Swift GRB 210818A: Global MASTER-Net observations report
  55. GRB 210818A: Swift-XRT refined Analysis
  56. GRB 210818A: Swift-BAT refined analysis
  57. GRB 210726A: VLA radio afterglow detection
  58. Konus-Wind detection of GRB 210818A
  59. GRB 210818A: AstroSat CZTI detection
  60. GRB 210818A: AGILE detection
  61. GRB 210818A: Enhanced Swift-XRT position
  62. GRB 210818A: Swift detection of a burst with an optical counterpart
  63. IceCube-210811A: Upper limits from Fermi-GBM Observations
  64. GRB 210815A: BALROG localization (Fermi Trigger 650687034 / GRB 210815100)
  65. GRB 210815A: Fermi GBM Final Real-time Localization
  66. GRB 210812A is consistent with being a lensed GRB
  67. GRB 210712A: Fermi GBM observation
  68. GRB 210813A: BALROG localization (Fermi Trigger 650508868 / GRB 210813038)
  69. Fermi GRB 210813A: Global MASTER-Net observations report
  70. GRB 210813A: Fermi GBM Final Real-time Localization
  71. Retraction of Fermi GBM GCN 30630 and GCN 30632
  72. GRB 210807A: continued Assy, AbAO and Mondy observations
  73. Fermi GRB 210812A: Global MASTER-Net observations report
  74. GRB 210812B: Fermi GBM Final Real-time Localization
  75. GRB 210812A: BALROG localization (Fermi Trigger 650479626 / GRB 210812699)
  76. GRB 210812A: Fermi GBM Final Real-time Localization
  77. GRB 080102A: Fermi GBM Final Real-time Localization
  78. SGR 1935+2154: SPI INTEGRAL observations on 2021 August 5
  79. GRB 080101A: Fermi GBM Final Real-time Localization
  80. GRB 210730A: Tautenburg observations
  81. GRB 210807A: Tautenburg observations
  82. GRB 210807C: Swift-BAT refined analysis
  83. GRB 210807A: Detection by GRBAlpha
  84. GRB 210807A: Swift-BAT refined analysis
  85. GRB 210802A: Further Swift/XRT observation and afterglow confirmation
  86. GRB 210807C: Swift-XRT refined Analysis
  87. GRB 210807C: Fermi GBM detection
  88. GRB 210807C: Swift/UVOT Upper Limits
  89. GRB 210807A: Swift/UVOT Detection
  90. GRB 210807A: Swift-XRT refined Analysis
  91. GRB 210807A: correction to the GCN Circ. #30614 Assy optical observations
  92. GRB 210807C: Enhanced Swift-XRT position
  93. GRB 210610B: Assy optical observations
  94. Fermi GRB 210807C: Global MASTER-Net observations report
  95. GRB 210807C: Swift detection of a burst
  96. GRB 210807C: Fermi GBM Final Real-time Localization
  97. Fermi GRB 210807B: Global MASTER-Net observations report
  98. Swift GRB 210807A: Global MASTER-Net observations report
  99. GRB 210807A: Enhanced Swift-XRT position
  100. GRB 210807A: BOOTES-5/JGT optical afterglow detection

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