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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"

27964 results found.

  1. GRB 210704A: AstroSat CZTI detection
  2. GRB 210704A: Fermi-LAT detection
  3. GRB 210704A: Swift ToO observations
  4. GRB 210705A: AGILE/MCAL detection of a burst
  5. GRB 210704A: AGILE/MCAL detection
  6. GRB 210702A, Swift-BAT refined analysis
  7. GRB 210702A: BOOTES-3/YA optical counterpart observations
  8. Konus-Wind detection of GRB 210702A
  9. GRB 210702A: Chilescope optical observations
  10. GRB 210702A: AGILE detection
  11. GRB 210702A: CALET Gamma-Ray Burst Monitor detection
  12. GRB 210619B: JCMT SCUBA-2 sub-mm observations
  13. GRB 210610B: JCMT SCUBA-2 sub-mm observations
  14. GRB 210610A: JCMT SCUBA-2 sub-mm observations
  15. GRB 210702A: Swift-XRT refined Analysis
  16. GRB 210702A: VLT/X-shooter redshift
  17. GRB 210702A: preliminary Swift/UVOT photometry
  18. GRB 210702A: Swift/UVOT redshift
  19. GRB210702A: MeerLICHT multi-colour photometry
  20. Swift GRB 210702A: Global MASTER-Net observations report
  21. Swift GRB210702.80: Global MASTER-Net OT detection
  22. GRB 210702A: Swift detection of a burst with a bright optical counterpart
  23. GRB 210627B: GECAM detection
  24. GRB 210619B: Sayan observatory 1.6-m telescope observations
  25. IceCube-210629A - IceCube observation of a high-energy neutrino candidate track-like event
  26. GRB 210626A: Swift/XRT afterglow confirmation
  27. GRB 210626A: Fermi GBM observation
  28. GRB 210626A: CAHA 2.2m telescope optical limit
  29. GRB 210619B: Deep CAHA 2.2m detection and late-time light curve behavior
  30. GRB 210626A: Ondrejov D50 optical limit
  31. GRB 210626A: GIT optical upper limit
  32. GRB 210627B: Fermi GBM Final Real-time Localization
  33. GRB 210627A: Fermi GBM Final Real-time Localization
  34. GRB 210626A: Swift-XRT afterglow detection
  35. GRB 210626A: Swift ToO observations
  36. GRB 210626A: Swift/BAT-GUANO detection and arcminute localization
  37. GRB 150428A: late-time radio observations
  38. GRB 210626A: Fermi GBM Final Real-time Localization
  39. GRB 210618A: 1.5m OSN optical upper limit
  40. GRB210619B: optical afterglow detection from Konkoly Observatory
  41. GRB 210625A: Fermi GBM Final Real-time Localization
  42. GRB 210622A: Swift-XRT observations
  43. GRB 210610B: T-CAT optical observations
  44. GRB 210619B: ASIM observation
  45. GRB 210618A: Swift-XRT afterglow detection
  46. GRB 210622A: Swift ToO observations
  47. GRB 210619B: Even further SAO RAS optical observations
  48. GRB 210622A: Fermi GBM detection
  49. GRB 210619B: Further SAO RAS optical observations
  50. GRB 210622A: Swift/BAT-GUANO detection and arcminute localization of a long burst
  51. GRB 210619B: possibility of lensed visible afterglow?
  52. GECAM detection of GRB 210622B
  53. GRB 210622B: Fermi GBM Final Real-time Localization
  54. GRB 210622A: Fermi GBM Final Real-time Localization
  55. Swift Trigger 1057131: detection of a burst from SGR Swift J1555.2-5402
  56. Swift GRB210621.71: Global MASTER-Net observations report
  57. GRB 210619B: NOT optical observations
  58. GRB 210619B: 1.5m OSN optical observation
  59. GRB 210619B: SAO RAS optical observations
  60. GRB 210619B: REM optical/NIR afterglow detection
  61. GRB 210619B: GIT optical follow-up and confirmation of jet-break
  62. GRB 210621A: Fermi GBM Final Real-time Localization
  63. GRB 210619B: CALET Gamma-Ray Burst Monitor detection
  64. GRB 210619B: SRG/ART-XC detection
  65. GRB 210619B: Swift-BAT refined analysis
  66. GRB 210619B: Liverpool Telescope First Hour Observations
  67. GRB 210619B: Fermi GBM detection
  68. GRB 210619B: Swift/UVOT Detection
  69. GRB 210619B: Xinglong TNT optical observations
  70. Konus-Wind detection of GRB 210619B
  71. GRB 210619B: CAHA 2.2m photometric monitoring
  72. GRB 210619B: Liverpool Telescope r'-band observations
  73. GRB 210619B: KAIT Optical Detection
  74. GRB 210619B: Redshift from OSIRIS/GTC
  75. GRB 210619B: Fermi-LAT detection
  76. GRB 210619B: Swift-XRT refined Analysis
  77. GRB 210619B: SARA-KP 0.9m Optical Afterglow Detection
  78. GRB 210619B: Enhanced Swift-XRT position
  79. GRB 210619B: iTelescope T18 detection
  80. GECAM detection of GRB 210619B
  81. GRB 210619B: Ondrejov D50 detection
  82. Swift GRB210619.99: Global MASTER-Net OT detection
  83. GRB 210619B: Swift detection of a bright burst and optical counterpart
  84. Swift GRB210619.99: Global MASTER-Net observations report
  85. Swift GRB210619.99: Global MASTER-Net OT detection
  86. GRB 210619A: Fermi GBM Final Real-time Localization
  87. GRB 210618A: Swift/UVOT Upper Limits
  88. GRB 210618A: BOOTES-2/TELMA optical upper limit
  89. GRB 210618A: Swift-BAT refined analysis
  90. GRB 210618A: Fermi GBM observation
  91. GRB 210618A: Swift-XRT observations
  92. GRB 210618A: DDOTI upper limit for the optical afterglow
  93. GRB 210618A: Swift detection of a burst
  94. Swift GRB210618.07: Global MASTER-Net observations report
  95. GRB 210618A: Fermi GBM Final Real-time Localization
  96. GRB 210610B: Swift/UVOT Detection
  97. GRB 210610A: Swift/UVOT Detection
  98. GRB 201008A: Fermi GBM observation
  99. GRB 210323B: Fermi GBM observation
  100. GRB 210615A: Fermi GBM Final Real-time Localization

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