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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"

36197 results found.

  1. GRB 210605B: Swift-XRT afterglow detection
  2. GRB 210610A: Fermi GBM observations
  3. GRB 210610A: CAHA 2.2m Second Epoch
  4. GRB 210610B: iTelescope optical afterglow observations
  5. GRB 210610B: Further SAO RAS optical observations
  6. GRB 210610A: SAO RAS optical observations
  7. GRB 210610B: optical observations from Burke-Gaffney Observatory and Abbey Ridge Observatory
  8. GRB 210610B: Continued KAIT Optical Detection
  9. GRB 210610B: optical photometry of afterglow at INASAN/Simeiz
  10. GRB 210421B: Fermi GBM detection
  11. GRB 210607C: AstroSat CZTI detection
  12. Swift-BAT Trigger 1055000: Swift detection of an outburst from 4U 1543-47
  13. GRB210610B: SARA-KP 0.9m Optical Afterglow Detection
  14. GRB 210610B: MITSuME Akeno optical observation
  15. GRB 201228B: Fermi GBM observation
  16. GRB 210610B: VLA detection
  17. GRB 210610B: ALMA detection
  18. GRB 210610B: Liverpool Telescope optical photometry
  19. GRB 210610B: CrAO/ZTSH optical observations and light curve
  20. GRB 210610A: CrAO/ZTSH optical observations
  21. GRB 210610B: CrAO/ZTSH optical observations (correction to the GCN circ. 30212)
  22. GRB 210610A: CrAO/ZTSH optical observations
  23. GRB 210610A: CAHA 2.2m observations and light-curve behavior
  24. GRB 210606A: Fermi GBM detection
  25. GRB 210605B: Fermi GBM detection
  26. GRB 210610B: Swift-XRT refined Analysis
  27. GRB 210610B: Swift-BAT refined analysis
  28. GRB 210610B: Zwicky Transient Facility afterglow detection
  29. GRB 210610B: optical afterglow observations
  30. GRB 210610B: KAIT Optical Detection
  31. GRB 210610A: KAIT Optical Detection
  32. GRB 210607C: Insight-HXMT/HE detection
  33. GRB 210610B: Spectroscopy and redshift confirmation with the Himalayan Chandra Telescope
  34. GRB 210610A: Spectroscopy and redshift confirmation with the Himalayan Chandra Telescope
  35. GRB 210610B: Fermi GBM detection
  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 210610B: GOTO confirmation of afterglow detection
  42. GRB 210610A: Swift-XRT refined Analysis
  43. GRB 210610A: RATIR Optical and NIR Detection
  44. GRB 210610B: RATIR Optical and NIR Observations
  45. GRB 210610B: Enhanced Swift-XRT position
  46. GRB 210610B: Photometry and phot-redshift from Legacy Survey, PanSTAR, and SDSS
  47. GRB 210610B: SAO RAS optical observations
  48. GRB 210610A: Swift-BAT refined analysis
  49. GRB 210610A: 1.5m OSN optical observation
  50. GRB 210610B: correction to GCN 30181
  51. GRB 210610B: NOT optical observations and tentative redshift
  52. GRB 210610B: iTelescope optical afterglow observations
  53. GRB 210610B: CrAO/ZTSh optical afterglow photometry
  54. GRB 210610B: BOOTES-2/TELMA optical observation
  55. Swift GRB 210610B: Global MASTER-Net observations report
  56. GRB 210610B: CrAO/ZTSh optical observations
  57. GRB 210610B: GIT optical detection
  58. GRB 210606A: Swift-XRT afterglow detection
  59. GRB 210610B: BALROG localization (Fermi Trigger 645047470 / GRB 210610827)
  60. GRB 210610B: Swift detection of a burst with bright optical afterglow
  61. GRB 210610A: MITSuME Ishigaki optical observation
  62. Swift GRB 210610A: Global MASTER-Net observations report
  63. Swift GRB 210610A: MASTER optical counterpart observation
  64. GRB 210610A: Enhanced Swift-XRT position
  65. GRB 210610A: Xinglong-2.16m redshift
  66. GRB 210610A: GIT optical detection
  67. GRB 210610A: Xinglong-2.16m optical afterglow observations
  68. GRB 210610A: MITSuME Akeno optical observation
  69. GRB 210610A: Swift detection of a burst with an optical counterpart
  70. GRB 210607B: Insight-HXMT/HE detection
  71. GRB 210605A: CALET Gamma-Ray Burst Monitor detection
  72. Konus-Wind detection of GRB 210606B
  73. IPN triangulation of GRB 210606B
  74. Fermi Gamma-ray Burst Monitor trigger 644793834 / 210607892 is not a GRB
  75. GRB 210607A/MAXI J1733-222: MAXI/GSC detection
  76. GRB 210606B: Fermi GBM detection
  77. GRB 210605B: Swift-XRT observations
  78. Konus-Wind detection of GRB 210602A
  79. Konus-Wind detection of GRB 210605A (short/hard)
  80. IPN triangulation of GRB 210605A (short)
  81. GRB 210606B: AGILE detection
  82. GRB 210606A: 1.5m OSN optical upper limit
  83. GRB 210606B: BALROG localization (Fermi Trigger 644712030 / GRB 210606945)
  84. GRB 210606B: GECAM detection
  85. GRB 210606A: Swift ToO observations
  86. Fermi GRB 210606A: DDOTI Upper Limits on the Afterglow
  87. GRB 210606A: Swift/BAT-GUANO detection and arcminute localization
  88. GRB 210605B: Swift ToO observations
  89. Fermi GRB 210606A: Global MASTER-Net observations report
  90. GRB 210606A: Fermi GBM Final Real-time Localization
  91. GRB 210605B: Swift/BAT-GUANO detection and arcminute localization
  92. GRB 210605B: Fermi GBM Final Real-time Localization
  93. Fermi GRB 210605A: Global MASTER-Net observations report
  94. GRB 210605A: Fermi GBM Final Real-time Localization
  95. Fermi GBM Sub-Threshold Detection of new Swift SGR J1555.2-5402
  96. GRB 210602A: CALET Gamma-Ray Burst Monitor detection
  97. GRB 210602B: GECAM detection
  98. GRB 210529A: GECAM detection
  99. GRB 210602A: MAXI/GSC detection
  100. Fermi GRB 210601A: Global MASTER-Net observations report

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