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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"

11855 results found.

  1. GRB 210619B: possibility of lensed visible afterglow?
  2. Swift GRB210621.71: Global MASTER-Net observations report
  3. GRB 210619B: 1.5m OSN optical observation
  4. GRB 210619B: iTelescope optical afterglow observation
  5. GRB 210619B: SAO RAS optical observations
  6. GRB 210619B: REM optical/NIR afterglow detection
  7. GRB 210619B: Liverpool Telescope First Hour Observations
  8. GRB 210619B: Swift/UVOT Detection
  9. Konus-Wind detection of GRB 210619B
  10. GRB 210619B: CAHA 2.2m photometric monitoring
  11. GRB 210619B: Liverpool Telescope r'-band observations
  12. GRB 210619B: Liverpool telescope imaging of a red afterglow
  13. GRB 210619B: Fermi-LAT detection
  14. GRB 210619B: SARA-KP 0.9m Optical Afterglow Detection
  15. Fermi trigger No 645857659: Global MASTER-Net observations report
  16. GRB 210619B: iTelescope T18 detection
  17. Swift GRB210619.99: Global MASTER-Net OT detection
  18. Swift GRB210619.99: Global MASTER-Net observations report
  19. Swift GRB210619.99: Global MASTER-Net OT detection
  20. Swift GRB210618.07: Global MASTER-Net observations report
  21. GRB 210610B: CrAO/ZTSH continued optical observations and light curve
  22. Fermi trigger No 645485036: Global MASTER-Net observations report
  23. Fermi GRB 210615A: Global MASTER-Net observations report
  24. Swift ToO Observations of HAWC transient J0020+3108
  25. GRB 210610B: iTelescope optical afterglow observations
  26. GRB 210610B: Further SAO RAS optical observations
  27. GRB 210610A: SAO RAS optical observations
  28. GRB 210610B: optical observations from Burke-Gaffney Observatory and Abbey Ridge Observatory
  29. GRB 210610B: optical photometry of afterglow at INASAN/Simeiz
  30. GRB 210607C: AstroSat CZTI detection
  31. GRB210610B: SARA-KP 0.9m Optical Afterglow Detection
  32. GRB 210610B: MITSuME Akeno optical observation
  33. GRB 210610B: CrAO/ZTSH optical observations and light curve
  34. GRB 210610B: Swift-XRT refined Analysis
  35. GRB 210610B: optical afterglow observations
  36. GRB 210610B: University of Siena Observatory optical photometry of the afterglow
  37. Konus-Wind detection of GRB 210610A
  38. Konus-Wind detection of GRB 210610B
  39. GRB 210610B: AGILE detection
  40. GRB 210610B: Redshift confirmation from GTC
  41. GRB 210610A: Swift-XRT refined Analysis
  42. GRB 210610B: SAO RAS optical observations
  43. Fermi trigger No 645047470: Global MASTER-Net observations report
  44. GRB 210610B: CrAO/ZTSh optical afterglow photometry
  45. GRB 210610B: BOOTES-2/TELMA optical observation
  46. Swift GRB 210610B: Global MASTER-Net observations report
  47. GRB 210610B: CrAO/ZTSh optical observations
  48. Swift GRB210610.83: Global MASTER-Net OT detection
  49. GRB 210606A: Swift-XRT afterglow detection
  50. Swift GRB 210610A: Global MASTER-Net observations report
  51. Konus-Wind detection of GRB 210606B
  52. Fermi-LAT Gamma-ray Observations of IceCube-210608A
  53. GRB 210607A/MAXI J1733-222: MAXI/GSC detection
  54. Konus-Wind detection of GRB 210602A
  55. Konus-Wind detection of GRB 210605A (short/hard)
  56. GRB 210606B: AGILE detection
  57. GRB 210605B: Swift/BAT-GUANO detection and arcminute localization
  58. Swift GRB210603.41: Global MASTER-Net observations report
  59. Fermi trigger No 644359567: Global MASTER-Net observations report
  60. GRB 210602A: MAXI/GSC detection
  61. Fermi GRB 210601A: Global MASTER-Net observations report
  62. GRB 210531A: AstroSat CZTI detection
  63. Fermi trigger No 644155206: Global MASTER-Net observations report
  64. GRB 210531A: AGILE/MCAL detection (Fermi Trigger 644155206 / GRB 210531500)
  65. Fermi GRB 210529A: Global MASTER-Net observations report
  66. Fermi GRB 210529B: Global MASTER-Net observations report
  67. GRB 210528A: AstroSat CZTI detection
  68. MAXI GRB210528.95: Global MASTER-Net observations report
  69. GRB 210528B: MAXI/GSC detection
  70. Fermi GRB 210528A: Global MASTER-Net observations report
  71. GRB 210527A: Swift-XRT refined Analysis
  72. GRB 210527A: Swift-XRT observations
  73. Konus-Wind detection of GRB 210524A
  74. Fermi trigger No 643548039: Global MASTER-Net observations report
  75. GRB 210524B: Fermi GBM Final Real-time Localization
  76. GRB 210521A: MAXI/GSC detection
  77. GRB 210520A: Fermi GBM detection
  78. ZTF21aayokph (AT2021lfa): continued Assy optical observations
  79. GRB 210520A: Fermi-LAT detection
  80. Fermi GRB 210520A: Global MASTER-Net observations report
  81. GRB 210520A: Fermi GBM Final Real-time Localization
  82. IceCube Alert 210519.86: Global MASTER-Net observations report
  83. GRB 210518.889: DDOTI Upper Limits on the Afterglow
  84. Fermi GRB 210518A: Global MASTER-Net observations report
  85. Konus-Wind detection of GRB 210514A
  86. Fermi trigger No 642991619: Global MASTER-Net observations report
  87. Fermi-LAT Gamma-ray Observations of IceCube-210516A
  88. GRB 210517A: Swift-XRT refined Analysis
  89. IceCube-210516A: No significant detection in HAWC
  90. GRB 210517A: AGILE detection
  91. GRB 210517A: Swift detection of a burst
  92. IceCube Alert 210516.61: Global MASTER-Net observations report
  93. GRB 210515C: Swift-XRT refined Analysis
  94. GRB 210515C: Swift detection of a burst
  95. Fermi GRB 210515B: Global MASTER-Net observations report
  96. Fermi GRB 210515A: Global MASTER-Net observations report
  97. GRB 210514A: Swift-XRT refined Analysis
  98. AMON Coincidence Alert from the sub-threshold IceCube-HAWC search NuEM-210515A and 210515B
  99. Konus-Wind detection of GRB 210511B
  100. GRB 210512.786: DDOTI Upper Limits on the Afterglow

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