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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"

12172 results found.

  1. Swift GRB 210610B: Global MASTER-Net observations report
  2. GRB 210610B: CrAO/ZTSh optical observations
  3. Swift GRB210610.83: Global MASTER-Net OT detection
  4. GRB 210606A: Swift-XRT afterglow detection
  5. Swift GRB 210610A: Global MASTER-Net observations report
  6. Konus-Wind detection of GRB 210606B
  7. Fermi-LAT Gamma-ray Observations of IceCube-210608A
  8. GRB 210607A/MAXI J1733-222: MAXI/GSC detection
  9. Konus-Wind detection of GRB 210602A
  10. Konus-Wind detection of GRB 210605A (short/hard)
  11. GRB 210606B: AGILE detection
  12. GECAM Sub-Threshold Detection of new magnetar Swift SGR J1555.2-5402
  13. GRB 210605B: Swift/BAT-GUANO detection and arcminute localization
  14. Fermi GBM Sub-Threshold Detection of new Swift SGR J1555.2-5402
  15. SGR J1555.2-5402: Swift-BAT refined analysis
  16. Swift J1555.2-5402: Swift XRT refined analysis of the new SGR
  17. NICER discovery of 3.86 s pulsations from a new magnetar: SGR J1555.2-5402
  18. Swift Detection of probable new Swift SGR J1555.2-5402
  19. Swift GRB210603.41: Global MASTER-Net observations report
  20. Fermi trigger No 644359567: Global MASTER-Net observations report
  21. GRB 210602A: MAXI/GSC detection
  22. Fermi GRB 210601A: Global MASTER-Net observations report
  23. GRB 210531A: AstroSat CZTI detection
  24. Fermi trigger No 644155206: Global MASTER-Net observations report
  25. GRB 210531A: AGILE/MCAL detection (Fermi Trigger 644155206 / GRB 210531500)
  26. Fermi GRB 210529A: Global MASTER-Net observations report
  27. Fermi GRB 210529B: Global MASTER-Net observations report
  28. GRB 210528A: AstroSat CZTI detection
  29. MAXI GRB210528.95: Global MASTER-Net observations report
  30. GRB 210528B: MAXI/GSC detection
  31. Fermi GRB 210528A: Global MASTER-Net observations report
  32. GRB 210527A: Swift-XRT refined Analysis
  33. GRB 210527A: Swift-XRT observations
  34. Konus-Wind detection of GRB 210524A
  35. Fermi trigger No 643548039: Global MASTER-Net observations report
  36. GRB 210524B: Fermi GBM Final Real-time Localization
  37. GRB 210521A: MAXI/GSC detection
  38. GRB 210520A: Fermi GBM detection
  39. ZTF21aayokph (AT2021lfa): continued Assy optical observations
  40. GRB 210520A: Fermi-LAT detection
  41. Fermi GRB 210520A: Global MASTER-Net observations report
  42. GRB 210520A: Fermi GBM Final Real-time Localization
  43. Fermi GBM observation of a bright burst from magneta
  44. IceCube Alert 210519.86: Global MASTER-Net observations report
  45. GRB 210518.889: DDOTI Upper Limits on the Afterglow
  46. Fermi GRB 210518A: Global MASTER-Net observations report
  47. Konus-Wind detection of GRB 210514A
  48. Fermi trigger No 642991619: Global MASTER-Net observations report
  49. Fermi-LAT Gamma-ray Observations of IceCube-210516A
  50. GRB 210517A: Swift-XRT refined Analysis
  51. IceCube-210516A: No significant detection in HAWC
  52. GRB 210517A: AGILE detection
  53. GRB 210517A: Swift detection of a burst
  54. IceCube Alert 210516.61: Global MASTER-Net observations report
  55. GRB 210515C: Swift-XRT refined Analysis
  56. GRB 210515C: Swift detection of a burst
  57. Fermi GRB 210515B: Global MASTER-Net observations report
  58. Fermi GRB 210515A: Global MASTER-Net observations report
  59. GRB 210514A: Swift-XRT refined Analysis
  60. AMON Coincidence Alert from the sub-threshold IceCube-HAWC search NuEM-210515A and 210515B
  61. Konus-Wind detection of GRB 210511B
  62. GRB 210512.786: DDOTI Upper Limits on the Afterglow
  63. Fermi trigger No 642538568: Global MASTER-Net observations report
  64. Fermi-LAT Gamma-ray Observations of IceCube-210510A
  65. Fermi GRB 210511A: Global MASTER-Net observations report
  66. Fermi GRB 210511B: Global MASTER-Net observations report
  67. GRB 210511B: AGILE detection
  68. Fermi GRB 210510A: Global MASTER-Net observations report
  69. IceCube Alert 210510.20: Global MASTER-Net observations report
  70. GRB 210510A: Fermi GBM Final Real-time Localization
  71. GRB 210509A: Swift-XRT refined Analysis
  72. Swift GRB 210509A: Global MASTER-Net observations report
  73. GRB 210509A: Swift-XRT observations
  74. GRB 210509A: Swift detection of a burst
  75. Fermi GRB 210507A: Global MASTER-Net observations report
  76. Fermi-LAT Gamma-ray Observations of IceCube-210503A and detection of a new gamma-ray source, Fermi J0931.9+3633
  77. ZTF21aayokph (AT2021lfa): Assy optical observations
  78. GRB 210424B: AstroSat CZTI detection
  79. GRB 210504A: Swift/UVOT Detection
  80. Fermi GRB 210503A: Global MASTER-Net observations report
  81. Fermi GRB 210501A: Global MASTER-Net observations report
  82. Fermi trigger No 641601187: Global MASTER-Net observations report
  83. GRB 210430A: BOOTES-1 optical limit
  84. Konus-Wind detection of GRB 210424B
  85. IPN triangulation of GRB 210424B (short/hard)
  86. Fermi GRB 210427A: Global MASTER-Net observations report
  87. GRB 210420B: Assy optical observations
  88. Fermi trigger No 640975205: Global MASTER-Net observations report
  89. GRB 210424.694: DDOTI Upper Limits on the Afterglow
  90. GRB 210420B: follow-up photometry of optical afterglow at INASAN/Simeiz
  91. GRB 210420B: Zeiss-1000 of Koshka optical observations
  92. GRB 210421B: AstroSat CZTI detection
  93. GRB 210421A: GECAM detection
  94. GRB 210421B: AstroSat CZTI detection
  95. Swift GRB210422.74: Global MASTER-Net observations report
  96. Fermi Gamma-ray Burst Monitor trigger 210421C is not a GRB
  97. GRB 210420B: Swift-XRT refined Analysis
  98. GRB 210421C: Fermi GBM Final Real-time Localization
  99. GRB 210420B: Tautenburg observations
  100. GRB 210420B: Swift/UVOT Detection

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