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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"

39468 results found.

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

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