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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 210402A: LBT observations
  2. GRB 210402A: DDOTI Upper Limits
  3. Swift GRB210403.35: Global MASTER-Net observations report
  4. GRB 210402A: Swift-XRT refined Analysis
  5. GRB 210403A: Swift detection of a burst
  6. GRB 210402A: Montarrenti Observatory upper limit
  7. GRB 210402A: Swift detection of a burst
  8. Swift GRB210402.92: Global MASTER-Net observations report
  9. GRB 210323A: Insight-HXMT/HE detection
  10. GRB 210321A: OSN Upper Limit
  11. GRB 210323A: MASTER optical observation
  12. GRB 210323A: Swift-BAT refined analysis
  13. GRB 210323A: Gemini-North Optical Source Detection
  14. Short GRB 210323A: GTC Observations
  15. GRB 210323B: Swift ToO observations
  16. Konus-Wind detection of GRB 210323A (short)
  17. GRB 210323A: Swift/UVOT Upper Limits
  18. GRB 210323A: Kitab optical upper limit
  19. GRB 210323A: Fermi GBM detection
  20. GRB 210318A: Swift/UVOT Upper Limits
  21. GRB 210323A: Swift-XRT refined Analysis
  22. GRB 210323A: Enhanced Swift-XRT position
  23. Swift GRB 210323A: Global MASTER-Net observations report
  24. GRB 210323B: Swift/BAT-GUANO detection and possible arcminute localization
  25. GRB 210323A: Swift detection of a short burst
  26. GRB 210321A: Swift/UVOT Detection
  27. Konus-Wind detection of GRB 210321A
  28. GRB 210318B: Swift/UVOT Upper Limits
  29. GRB 210321A: Swift-BAT refined analysis
  30. IceCube 135113_19489408.amon: Swift-XRT observations
  31. GRB 210321A: Swift-XRT refined Analysis
  32. GRB 210321A: NOT optical afterglow detection and redshift limit
  33. GRB 210321A: MASTER optical observation
  34. GRB 210321A: Enhanced Swift-XRT position
  35. GRB 210321A: DDOTI Afterglow Confirmation
  36. GRB 210321A: Swift/UVOT Detection
  37. GRB 210321A: Swift-XRT observations
  38. GRB 210321A: Swift detection of a burst
  39. GRB 210318B: MITSuME Okayama optical upper limits
  40. GRB 210318A: Swift-BAT refined analysis
  41. GRB 210318A: Swift-XRT refined Analysis
  42. GRB 210318A: Enhanced Swift-XRT position
  43. Swift GRB210318.13: Global MASTER-Net observations report
  44. GRB 210318B: Fermi GBM detection
  45. GRB 210318B: Swift-BAT refined analysis
  46. Swift GRB 210318A: Global MASTER-Net observations report
  47. Konus-Wind detection of GRB 210318B
  48. GRB210318B: Swift detection of a burst
  49. GRB 210318A: Swift detection of a burst
  50. GRB 210306A: GIT optical follow-up
  51. GRB 210226A: GIT optical upper limit
  52. GRB 210306A: HCT optical upper limit
  53. Konus-Wind detection of GRB 210308A
  54. Konus-Wind detection of GRB 210306A
  55. Konus-Wind detection of GRB 210305A
  56. GRB 210306A: Early Spectroscopy of the Optical Afterglow
  57. GRB 210306B: Fermi GBM detection
  58. GRB 210306A: Swift/UVOT Detection
  59. GRB 210308A: Swift-BAT refined analysis
  60. GRB 210307A: Swift-BAT refined analysis
  61. GRB 210308A: Swift/UVOT Detection
  62. GRB 210307A: Swift/UVOT Upper Limits
  63. GRB 210305A: Fermi GBM observation
  64. Swift GRB 210308A: Global MASTER-Net observations report
  65. GRB 210308A: Fermi GBM detection
  66. GRB 210305A: Swift-XRT refined Analysis
  67. GRB 210307A: Swift-XRT refined Analysis
  68. GRB 210306A: Swift-XRT refined Analysis
  69. GRB 210308A: MITSuME Okayama optical upper limits
  70. GRB 210308A: Swift detection of a burst with an optical counterpart
  71. GRB 210306A: Swift-BAT refined analysis
  72. GRB 210305A: Swift/UVOT Upper Limits
  73. GRB 210307A: LCO Optical Upper Limits
  74. GRB 210306B: Swift-BAT refined analysis
  75. GRB 210305A: Swift-BAT refined analysis
  76. GRB 210307A: Swift detection of a burst
  77. Swift GRB210307.36: Global MASTER-Net observations report
  78. GRB 210306A: MITSuME Akeno optical observation
  79. Swift GRB 210306A: Global MASTER-Net observations report
  80. GRB 210306A: Fermi GBM observation
  81. GRB 210306A: Fermi-LAT detection
  82. GRB 210306B: Swift detection of a burst
  83. GRB 210306A: LCO Optical Afterglow Detection
  84. GRB 210306A: DDOTI Afterglow Confirmation
  85. GRB 210306A: Swift detection of a burst with a bright optical counterpart
  86. Swift GRB 210305A: Global MASTER-Net observations report
  87. GRB 210305A: Swift detection of a burst
  88. Trigger 1035744: Swift detection of Sco X-1 due to Star Tracker loss of lock
  89. GRB 210226A: Swift/UVOT Upper Limits
  90. GRB 210226A: Swift-BAT refined analysis
  91. GRB 210226A: Fermi GBM detection
  92. GRB 210226A: KAIT Optical Upper Limit
  93. GRB 210226A: Swift-XRT refined Analysis
  94. Swift GRB 210226A: Global MASTER-Net observations report
  95. GRB 210218A: Swift-XRT confirmation of afterglow
  96. GRB 210226A: Enhanced Swift-XRT position
  97. GRB 210222B: 1.3m DFOT Optical upper limit
  98. GRB 210226A: Swift detection of a burst
  99. GRB 210222B: MITSuME Akeno optical upper limits
  100. GRB 210222B: Swift-BAT refined analysis

Advanced

Download all Circulars as a .tar.gz archive (updated once a day):
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