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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"

26127 results found.

  1. GRB 210619B: Redshift from OSIRIS/GTC
  2. GRB 210619B: Liverpool telescope imaging of a red afterglow
  3. GRB 210619B: Fermi-LAT detection
  4. GRB 210619B: Swift-XRT refined Analysis
  5. GRB 210619B: SARA-KP 0.9m Optical Afterglow Detection
  6. GRB 210619B: Enhanced Swift-XRT position
  7. GRB 210619B: iTelescope T18 detection
  8. GECAM detection of GRB 210619B
  9. GRB 210619B: Ondrejov D50 detection
  10. Swift GRB210619.99: Global MASTER-Net OT detection
  11. GRB 210619B: Swift detection of a bright burst and optical counterpart
  12. Swift GRB210619.99: Global MASTER-Net observations report
  13. Swift GRB210619.99: Global MASTER-Net OT detection
  14. GRB 210618A: Swift/UVOT Upper Limits
  15. GRB 210618A: BOOTES-2/TELMA optical upper limit
  16. GRB 210618A: Swift-BAT refined analysis
  17. GRB 210618A: Fermi GBM observation
  18. GRB 210618A: Swift-XRT observations
  19. GRB 210618A: DDOTI upper limit for the optical afterglow
  20. GRB 210618A: Swift detection of a burst
  21. Swift GRB210618.07: Global MASTER-Net observations report
  22. GRB 210610B: Swift/UVOT Detection
  23. GRB 210610A: Swift/UVOT Detection
  24. GRB 210610B: CrAO/ZTSH continued optical observations and light curve
  25. GRB 210610B: AbAO optical observations
  26. GRB 201008A: Fermi GBM observation
  27. GRB 210323B: Fermi GBM observation
  28. GRB 210610B: REM optical/NIR observations of the afterglow
  29. Swift-BAT Trigger 1055000/GRB210612.54: MASTER optical source observation
  30. Swift ToO Observations of HAWC transient J0020+3108
  31. GRB 210605B: Swift-XRT afterglow detection
  32. GRB 210610A: Fermi GBM observations
  33. GRB 210610A: CAHA 2.2m Second Epoch
  34. GRB 210610B: iTelescope optical afterglow observations
  35. GRB 210610B: optical observations from Burke-Gaffney Observatory and Abbey Ridge Observatory
  36. GRB 210610B: Continued KAIT Optical Detection
  37. GRB 210610B: optical photometry of afterglow at INASAN/Simeiz
  38. GRB 210421B: Fermi GBM detection
  39. Swift GRB210612.54: Global MASTER-Net observations report
  40. Swift-BAT Trigger 1055000: Swift detection of an outburst from 4U 1543-47
  41. GRB210610B: SARA-KP 0.9m Optical Afterglow Detection
  42. GRB 210610B: MITSuME Akeno optical observation
  43. GRB 201228B: Fermi GBM observation
  44. GRB 210610B: VLA detection
  45. GRB 210610B: Liverpool Telescope optical photometry
  46. GRB 210610B: CrAO/ZTSH optical observations and light curve
  47. GRB 210610A: CrAO/ZTSH optical observations
  48. GRB 210610B: CrAO/ZTSH optical observations (correction to the GCN circ. 30212)
  49. GRB 210610A: CrAO/ZTSH optical observations
  50. GRB 210610A: CAHA 2.2m observations and light-curve behavior
  51. GRB 210606A: Fermi GBM detection
  52. GRB 210605B: Fermi GBM detection
  53. GRB 210610B: Swift-XRT refined Analysis
  54. GRB 210610B: Swift-BAT refined analysis
  55. GRB 210610B: Zwicky Transient Facility afterglow detection
  56. GRB 210610B: optical afterglow observations
  57. GRB 210610B: KAIT Optical Detection
  58. GRB 210610A: KAIT Optical Detection
  59. GRB 210610B: Spectroscopy and redshift confirmation with the Himalayan Chandra Telescope
  60. GRB 210610A: Spectroscopy and redshift confirmation with the Himalayan Chandra Telescope
  61. GRB 210610B: Fermi GBM detection
  62. GRB 210610B: University of Siena Observatory optical photometry of the afterglow
  63. Konus-Wind detection of GRB 210610A
  64. Konus-Wind detection of GRB 210610B
  65. GRB 210610B: AGILE detection
  66. GRB 210610B: Redshift confirmation from GTC
  67. GRB 210610B: GOTO confirmation of afterglow detection
  68. GRB 210610A: Swift-XRT refined Analysis
  69. GRB 210610A: RATIR Optical and NIR Detection
  70. GRB 210610B: RATIR Optical and NIR Observations
  71. GRB 210610B: Enhanced Swift-XRT position
  72. GRB 210610B: Photometry and phot-redshift from Legacy Survey, PanSTAR, and SDSS
  73. GRB 210610B: SAO RAS optical observations
  74. GRB 210610A: Swift-BAT refined analysis
  75. GRB 210610A: 1.5m OSN optical observation
  76. GRB 210610B: correction to GCN 30181
  77. GRB 210610B: NOT optical observations and tentative redshift
  78. GRB 210610B: iTelescope optical afterglow observations
  79. GRB210610B: MeerLICHT multi-colour photometry
  80. GRB 210610B: CrAO/ZTSh optical afterglow photometry
  81. GRB 210610B: BOOTES-2/TELMA optical observation
  82. Swift GRB 210610B: Global MASTER-Net observations report
  83. GRB 210610B: CrAO/ZTSh optical observations
  84. GRB 210610B: GIT optical detection
  85. Swift GRB210610.83: Global MASTER-Net OT detection
  86. GRB 210606A: Swift-XRT afterglow detection
  87. GRB 210610B: Swift detection of a burst with bright optical afterglow
  88. GRB 210610A: MITSuME Ishigaki optical observation
  89. GRB210610A: MeerLICHT multi-colour photometry
  90. Swift GRB 210610A: Global MASTER-Net observations report
  91. Swift GRB 210610A: MASTER optical counterpart observation
  92. GRB 210610A: Enhanced Swift-XRT position
  93. GRB 210610A: Xinglong-2.16m redshift
  94. GRB 210610A: GIT optical detection
  95. GRB 210610A: Xinglong-2.16m optical afterglow observations
  96. GRB 210610A: MITSuME Akeno optical observation
  97. GRB 210610A: Swift detection of a burst with an optical counterpart
  98. IPN triangulation of GRB 210606B
  99. GRB 210605B: Swift-XRT observations
  100. IPN triangulation of GRB 210605A (short)

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