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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"

19663 results found.

  1. GRB 210704A: Swift ToO observations
  2. GRB 210702A, Swift-BAT refined analysis
  3. GRB 210702A: BOOTES-3/YA optical counterpart observations
  4. Konus-Wind detection of GRB 210702A
  5. GRB 210702A: Chilescope optical observations
  6. GRB 210702A: AGILE detection
  7. GRB 210702A: CALET Gamma-Ray Burst Monitor detection
  8. GRB 210619B: JCMT SCUBA-2 sub-mm observations
  9. GRB 210610B: JCMT SCUBA-2 sub-mm observations
  10. GRB 210610A: JCMT SCUBA-2 sub-mm observations
  11. GRB 210702A: Swift-XRT refined Analysis
  12. GRB 210702A: VLT/X-shooter redshift
  13. GRB 210702A: preliminary Swift/UVOT photometry
  14. GRB 210702A: Swift/UVOT redshift
  15. GRB210702A: MeerLICHT multi-colour photometry
  16. Swift GRB 210702A: Global MASTER-Net observations report
  17. Swift GRB210702.80: Global MASTER-Net OT detection
  18. GRB 210702A: Swift detection of a burst with a bright optical counterpart
  19. GRB 210619B: Sayan observatory 1.6-m telescope observations
  20. GRB 210626A: Swift/XRT afterglow confirmation
  21. GRB 210626A: Fermi GBM observation
  22. GRB 210626A: CAHA 2.2m telescope optical limit
  23. GRB 210626A: Ondrejov D50 optical limit
  24. GRB 210626A: GIT optical upper limit
  25. GRB 210626A: Swift-XRT afterglow detection
  26. GRB 210626A: Swift ToO observations
  27. GRB 210626A: Swift/BAT-GUANO detection and arcminute localization
  28. GRB 150428A: late-time radio observations
  29. GRB 210618A: 1.5m OSN optical upper limit
  30. GRB 210622A: Swift-XRT observations
  31. GRB 210619B: ASIM observation
  32. GRB 210618A: Swift-XRT afterglow detection
  33. GRB 210622A: Swift ToO observations
  34. GRB 210619B: Even further SAO RAS optical observations
  35. GRB 210622A: Fermi GBM detection
  36. GRB 210619B: Further SAO RAS optical observations
  37. GRB 210622A: Swift/BAT-GUANO detection and arcminute localization of a long burst
  38. Swift Trigger 1057131: detection of a burst from SGR Swift J1555.2-5402
  39. Swift GRB210621.71: Global MASTER-Net observations report
  40. GRB 210619B: NOT optical observations
  41. GRB 210619B: 1.5m OSN optical observation
  42. GRB 210619B: SAO RAS optical observations
  43. GRB 210619B: GIT optical follow-up and confirmation of jet-break
  44. GRB 210619B: CALET Gamma-Ray Burst Monitor detection
  45. GRB 210619B: SRG/ART-XC detection
  46. GRB 210619B: Swift-BAT refined analysis
  47. GRB 210619B: Liverpool Telescope First Hour Observations
  48. GRB 210619B: Fermi GBM detection
  49. GRB 210619B: Swift/UVOT Detection
  50. GRB 210619B: Xinglong TNT optical observations
  51. Konus-Wind detection of GRB 210619B
  52. GRB 210619B: CAHA 2.2m photometric monitoring
  53. GRB 210619B: Liverpool Telescope r'-band observations
  54. GRB 210619B: KAIT Optical Detection
  55. GRB 210619B: Redshift from OSIRIS/GTC
  56. GRB 210619B: Fermi-LAT detection
  57. GRB 210619B: Swift-XRT refined Analysis
  58. GRB 210619B: SARA-KP 0.9m Optical Afterglow Detection
  59. GRB 210619B: Enhanced Swift-XRT position
  60. GECAM detection of GRB 210619B
  61. Swift GRB210619.99: Global MASTER-Net OT detection
  62. GRB 210619B: Swift detection of a bright burst and optical counterpart
  63. Swift GRB210619.99: Global MASTER-Net observations report
  64. Swift GRB210619.99: Global MASTER-Net OT detection
  65. GRB 210618A: Swift/UVOT Upper Limits
  66. GRB 210618A: BOOTES-2/TELMA optical upper limit
  67. GRB 210618A: Swift-BAT refined analysis
  68. GRB 210618A: Fermi GBM observation
  69. GRB 210618A: Swift-XRT observations
  70. GRB 210618A: DDOTI upper limit for the optical afterglow
  71. GRB 210618A: Swift detection of a burst
  72. Swift GRB210618.07: Global MASTER-Net observations report
  73. GRB 210610B: Swift/UVOT Detection
  74. GRB 210610A: Swift/UVOT Detection
  75. GRB 201008A: Fermi GBM observation
  76. GRB 210323B: Fermi GBM observation
  77. Swift-BAT Trigger 1055000/GRB210612.54: MASTER optical source observation
  78. Swift ToO Observations of HAWC transient J0020+3108
  79. GRB 210605B: Swift-XRT afterglow detection
  80. GRB 210610A: Fermi GBM observations
  81. GRB 210610A: CAHA 2.2m Second Epoch
  82. GRB 210421B: Fermi GBM detection
  83. Swift GRB210612.54: Global MASTER-Net observations report
  84. Swift-BAT Trigger 1055000: Swift detection of an outburst from 4U 1543-47
  85. GRB210610B: SARA-KP 0.9m Optical Afterglow Detection
  86. GRB 210610B: MITSuME Akeno optical observation
  87. GRB 201228B: Fermi GBM observation
  88. GRB 210610B: VLA detection
  89. GRB 210610A: CAHA 2.2m observations and light-curve behavior
  90. GRB 210606A: Fermi GBM detection
  91. GRB 210605B: Fermi GBM detection
  92. GRB 210610B: Swift-XRT refined Analysis
  93. GRB 210610B: Swift-BAT refined analysis
  94. GRB 210610B: KAIT Optical Detection
  95. GRB 210610A: KAIT Optical Detection
  96. GRB 210610B: Spectroscopy and redshift confirmation with the Himalayan Chandra Telescope
  97. GRB 210610A: Spectroscopy and redshift confirmation with the Himalayan Chandra Telescope
  98. GRB 210610B: Fermi GBM detection
  99. GRB 210610B: University of Siena Observatory optical photometry of the afterglow
  100. Konus-Wind detection of GRB 210610A

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