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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"

39469 results found.

  1. Fermi trigger No 645047470: Global MASTER-Net observations report
  2. GRB 210610B: CrAO/ZTSh optical afterglow photometry
  3. GRB 210610B: BOOTES-2/TELMA optical observation
  4. Swift GRB 210610B: Global MASTER-Net observations report
  5. GRB 210610B: CrAO/ZTSh optical observations
  6. GRB 210610B: GIT optical detection
  7. Swift GRB210610.83: Global MASTER-Net OT detection
  8. GRB 210606A: Swift-XRT afterglow detection
  9. GRB 210610B: BALROG localization (Fermi Trigger 645047470 / GRB 210610827)
  10. GRB 210610B: Swift detection of a burst with bright optical afterglow
  11. GRB 210610A: MITSuME Ishigaki optical observation
  12. GRB210610A: MeerLICHT multi-colour photometry
  13. Swift GRB 210610A: Global MASTER-Net observations report
  14. Swift GRB 210610A: MASTER optical counterpart observation
  15. GRB 210610A: Enhanced Swift-XRT position
  16. GRB 210610A: Xinglong-2.16m redshift
  17. GRB 210610A: GIT optical detection
  18. GRB 210610A: Xinglong-2.16m optical afterglow observations
  19. GRB 210610A: MITSuME Akeno optical observation
  20. GRB 210610A: Swift detection of a burst with an optical counterpart
  21. GRB 210607B: Insight-HXMT/HE detection
  22. GRB 210605A: CALET Gamma-Ray Burst Monitor detection
  23. Konus-Wind detection of GRB 210606B
  24. Fermi-LAT Gamma-ray Observations of IceCube-210608A
  25. IPN triangulation of GRB 210606B
  26. IceCube-210608A: IceCube observation of a high-energy neutrino candidate track-like event
  27. IceCube Alert 210608.15: Global MASTER-Net observations report
  28. Fermi Gamma-ray Burst Monitor trigger 644793834 / 210607892 is not a GRB
  29. GRB 210607A/MAXI J1733-222: MAXI/GSC detection
  30. MAXI GRB210607.82: Global MASTER-Net observations report
  31. Fermi trigger No 644793834: Global MASTER-Net observations report
  32. GRB 210606B: Fermi GBM detection
  33. GRB 210605B: Swift-XRT observations
  34. Konus-Wind detection of GRB 210602A
  35. Konus-Wind detection of GRB 210605A (short/hard)
  36. IPN triangulation of GRB 210605A (short)
  37. GRB 210606B: AGILE detection
  38. GRB 210606A: 1.5m OSN optical upper limit
  39. GRB 210606B: BALROG localization (Fermi Trigger 644712030 / GRB 210606945)
  40. GRB 210606B: GECAM detection
  41. Fermi trigger No 644712030: Global MASTER-Net observations report
  42. GRB 210606A: Swift ToO observations
  43. Fermi GRB 210606A: DDOTI Upper Limits on the Afterglow
  44. GRB 210606A: Swift/BAT-GUANO detection and arcminute localization
  45. GRB 210605B: Swift ToO observations
  46. Fermi GRB 210606A: Global MASTER-Net observations report
  47. GRB 210606A: Fermi GBM Final Real-time Localization
  48. GRB 210605B: Swift/BAT-GUANO detection and arcminute localization
  49. GRB 210605B: Fermi GBM Final Real-time Localization
  50. Fermi GRB 210605A: Global MASTER-Net observations report
  51. GRB 210605A: Fermi GBM Final Real-time Localization
  52. Fermi GBM Sub-Threshold Detection of new Swift SGR J1555.2-5402
  53. Fermi trigger No 644449593: Global MASTER-Net observations report
  54. Swift Detection of probable new Swift SGR J1555.2-5402
  55. MAXI GRB210602.50: Global MASTER-Net observations report
  56. Swift GRB210603.41: Global MASTER-Net observations report
  57. GRB 210602A: CALET Gamma-Ray Burst Monitor detection
  58. GRB 210602B: GECAM detection
  59. GRB 210529A: GECAM detection
  60. Fermi trigger No 644359567: Global MASTER-Net observations report
  61. GRB 210602A: MAXI/GSC detection
  62. Fermi GRB 210601A: Global MASTER-Net observations report
  63. GRB 210601A: Fermi GBM Final Real-time Localization
  64. IPN triangulation of GRB 210531A
  65. GRB210529B: Zwicky Transient Facility Follow-Up of a Fermi Short GRB (Trigger 644025222)
  66. GRB 210531A: AstroSat CZTI detection
  67. Fermi trigger No 644155206: Global MASTER-Net observations report
  68. GRB 210531A: AGILE/MCAL detection (Fermi Trigger 644155206 / GRB 210531500)
  69. GRB 210531A: BALROG localization (Fermi Trigger 644155206 / GRB 210531500)
  70. GRB 210529B: DDOTI Upper Limits on the Afterglow
  71. Fermi GRB 210529A: Global MASTER-Net observations report
  72. Fermi GRB 210529B: Global MASTER-Net observations report
  73. GRB 210529B: Fermi GBM Final Real-time Localization
  74. GRB 210529A: Fermi GBM Final Real-time Localization
  75. GRB 210528A: Fermi GBM detection
  76. GRB 210528A: AstroSat CZTI detection
  77. GRB 210528B: DDOTI Upper Limits on the Afterglow
  78. GRB 210528B: MITSuME Akeno optical upper limits
  79. MAXI GRB210528.95: Global MASTER-Net observations report
  80. GRB 210528B: MAXI/GSC detection
  81. Fermi GRB 210528A: Global MASTER-Net observations report
  82. GRB 210527A: Swift-BAT refined analysis
  83. GRB 210528A: BALROG localization (Fermi Trigger 643903431 / GRB 210528586)
  84. GRB 210528A: Fermi GBM Final Real-time Localization
  85. GRB 210527A: Swift/UVOT Observations
  86. GRB 210527A: GIT optical upper limit
  87. GRB 210527A: MITSuME Akeno optical upper limits
  88. Swift GRB 210527A: Global MASTER-Net observations report
  89. GRB 210527A: Swift-XRT refined Analysis
  90. GRB 210527A: RATIR Optical and NIR Observations
  91. GRB 210527A: Enhanced Swift-XRT position
  92. GRB 210527A: Swift-XRT observations
  93. GRB 210527A: Swift detection of a burst
  94. GRB 210306A: LBT observations of the likely host galaxy
  95. Fermi GRB 210524B: DDOTI Upper Limits on the Afterglow
  96. Konus-Wind detection of GRB 210524A
  97. IPN triangulation of GRB 210524A
  98. Fermi trigger No 643548039: Global MASTER-Net observations report
  99. GRB 210524B: Fermi GBM Final Real-time Localization
  100. GRB 210524A: BALROG localization (Fermi Trigger 643525204 / GRB 210524208)

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