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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"

39465 results found.

  1. GRB 210619B: Swift/UVOT Detection
  2. GRB 210619B: Xinglong TNT optical observations
  3. Konus-Wind detection of GRB 210619B
  4. GRB 210619B: CAHA 2.2m photometric monitoring
  5. GRB 210619B: Liverpool Telescope r'-band observations
  6. GRB 210619B: KAIT Optical Detection
  7. GRB 210619B: Redshift from OSIRIS/GTC
  8. GRB 210619B: Liverpool telescope imaging of a red afterglow
  9. GRB 210619B: Fermi-LAT detection
  10. GRB 210619B: Swift-XRT refined Analysis
  11. GRB 210619B: SARA-KP 0.9m Optical Afterglow Detection
  12. GRB 210619B: Enhanced Swift-XRT position
  13. Fermi trigger No 645857659: Global MASTER-Net observations report
  14. GRB 210619B: iTelescope T18 detection
  15. GECAM detection of GRB 210619B
  16. GRB 210619B: Ondrejov D50 detection
  17. Swift GRB210619.99: Global MASTER-Net OT detection
  18. GRB 210619B: Swift detection of a bright burst and optical counterpart
  19. Swift GRB210619.99: Global MASTER-Net observations report
  20. Swift GRB210619.99: Global MASTER-Net OT detection
  21. GRB 210619A: BALROG localization (Fermi Trigger 645799548 / GRB 210619532)
  22. GRB 210619A: Fermi GBM Final Real-time Localization
  23. GRB 210618A: Swift/UVOT Upper Limits
  24. GRB 210618A: BOOTES-2/TELMA optical upper limit
  25. GRB 210618A: Swift-BAT refined analysis
  26. GRB 210618A: Fermi GBM observation
  27. GRB 210618A: Swift-XRT observations
  28. GRB 210618A: DDOTI upper limit for the optical afterglow
  29. GRB 210618A: Swift detection of a burst
  30. Swift GRB210618.07: Global MASTER-Net observations report
  31. GRB 210618A: Fermi GBM Final Real-time Localization
  32. GRB 210610B: Swift/UVOT Detection
  33. GRB 210610A: Swift/UVOT Detection
  34. GRB 210610B: CrAO/ZTSH continued optical observations and light curve
  35. Fermi trigger No 645485036: Global MASTER-Net observations report
  36. GRB 210610B: AbAO optical observations
  37. GRB 201008A: Fermi GBM observation
  38. GRB 210323B: Fermi GBM observation
  39. Fermi GRB 210615A: Global MASTER-Net observations report
  40. GRB 210615A: Fermi GBM Final Real-time Localization
  41. GRB 210610B: REM optical/NIR observations of the afterglow
  42. Swift-BAT Trigger 1055000/GRB210612.54: MASTER optical source observation
  43. GRB 210605B: Swift-XRT afterglow detection
  44. GRB 210610A: Fermi GBM observations
  45. GRB 210610A: CAHA 2.2m Second Epoch
  46. GRB 210610B: iTelescope optical afterglow observations
  47. GRB 210610B: Further SAO RAS optical observations
  48. GRB 210610A: SAO RAS optical observations
  49. GRB 210610B: optical observations from Burke-Gaffney Observatory and Abbey Ridge Observatory
  50. GRB 210610B: Continued KAIT Optical Detection
  51. GRB 210610B: optical photometry of afterglow at INASAN/Simeiz
  52. GRB 210421B: Fermi GBM detection
  53. Swift GRB210612.54: Global MASTER-Net observations report
  54. GRB 210607C: AstroSat CZTI detection
  55. Swift-BAT Trigger 1055000: Swift detection of an outburst from 4U 1543-47
  56. GRB210610B: SARA-KP 0.9m Optical Afterglow Detection
  57. GRB 210610B: MITSuME Akeno optical observation
  58. GRB 201228B: Fermi GBM observation
  59. GRB 210610B: VLA detection
  60. GRB 210610B: ALMA detection
  61. GRB 210610B: Liverpool Telescope optical photometry
  62. GRB 210610B: CrAO/ZTSH optical observations and light curve
  63. GRB 210610A: CrAO/ZTSH optical observations
  64. GRB 210610B: CrAO/ZTSH optical observations (correction to the GCN circ. 30212)
  65. GRB 210610A: CrAO/ZTSH optical observations
  66. GRB 210610A: CAHA 2.2m observations and light-curve behavior
  67. GRB 210606A: Fermi GBM detection
  68. GRB 210605B: Fermi GBM detection
  69. GRB 210610B: Swift-XRT refined Analysis
  70. GRB 210610B: Swift-BAT refined analysis
  71. GRB 210610B: Zwicky Transient Facility afterglow detection
  72. GRB 210610B: optical afterglow observations
  73. GRB 210610B: KAIT Optical Detection
  74. GRB 210610A: KAIT Optical Detection
  75. GRB 210607C: Insight-HXMT/HE detection
  76. GRB 210610B: Spectroscopy and redshift confirmation with the Himalayan Chandra Telescope
  77. GRB 210610A: Spectroscopy and redshift confirmation with the Himalayan Chandra Telescope
  78. GRB 210610B: Fermi GBM detection
  79. GRB 210610B: University of Siena Observatory optical photometry of the afterglow
  80. Konus-Wind detection of GRB 210610A
  81. Konus-Wind detection of GRB 210610B
  82. GRB 210610B: AGILE detection
  83. GRB 210610B: Redshift confirmation from GTC
  84. GRB 210610B: GOTO confirmation of afterglow detection
  85. GRB 210610A: Swift-XRT refined Analysis
  86. GRB 210610A: RATIR Optical and NIR Detection
  87. GRB 210610B: RATIR Optical and NIR Observations
  88. GRB 210610B: Enhanced Swift-XRT position
  89. GRB 210610B: Photometry and phot-redshift from Legacy Survey, PanSTAR, and SDSS
  90. GRB 210610B: SAO RAS optical observations
  91. GRB 210610A: Swift-BAT refined analysis
  92. GRB 210610A: 1.5m OSN optical observation
  93. GRB 210610B: correction to GCN 30181
  94. GRB 210610B: NOT optical observations and tentative redshift
  95. GRB 210610B: iTelescope optical afterglow observations
  96. GRB210610B: MeerLICHT multi-colour photometry
  97. Fermi trigger No 645047470: Global MASTER-Net observations report
  98. GRB 210610B: CrAO/ZTSh optical afterglow photometry
  99. GRB 210610B: BOOTES-2/TELMA optical observation
  100. Swift GRB 210610B: Global MASTER-Net observations report

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