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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"

19666 results found.

  1. GRB 200917A: Swift detection of a burst
  2. Swift-XRT observations of IceCube 200911A
  3. GRB 200914A: AGILE detection
  4. GRB 200914A: Swift-XRT observations
  5. GRB 200914A: Swift ToO observations
  6. IPN triangulation of GRB 200907A (short)
  7. GRB 200909B: Swift-BAT refined analysis
  8. Swift GRB200909.97: Global MASTER-Net observations report
  9. GRB 200909B: Swift detection of a burst
  10. GRB 200907B: Swift/UVOT Upper Limits
  11. GRB 200907B: Swift-BAT refined analysis
  12. GRB 200907B: AstroSat CZTI detection
  13. GRB 200907B: Swift-XRT refined Analysis
  14. GRB 200907B: MITSuME Okayama optical upper limits
  15. Swift GRB 200907B: Global MASTER-Net observations report
  16. GRB 200907B: Enhanced Swift-XRT position
  17. Correction to GCN 28387: GRB 200907B GROWTH-India optical upper limit
  18. GRB200907A: GROWTH-India optical upper limit
  19. GRB 200907B: Prompt enhanced Swift-XRT position
  20. GRB 200907B: Swift detection of a short burst
  21. GRB 200906A: EMIR/GTC NIR upper limit
  22. GRB 200906A: LBT near-infrared upper limit
  23. GRB 200906A: Swift-BAT refined analysis
  24. GRB 200906A: Swift/UVOT Upper Limits
  25. GRB 200906A: GROWTH-India Telescope (GIT) optical r band upper limit
  26. GRB 200906A: OSN 1.5m Upper Limit
  27. GRB 200906A: Swift-XRT refined Analysis
  28. GRB 200906A: Fermi GBM detection
  29. GRB 200906A: Enhanced Swift-XRT position
  30. GRB 200906A: Swift detection of a burst
  31. Swift Triggers 994723-994725 and 994727 are not GRBs.
  32. GRB 200903A: Fermi GBM detection
  33. GRB 200903A: Swift-BAT refined analysis
  34. GRB 200903A: CALET Gamma-Ray Burst Monitor detection
  35. Swift GRB200903.03: Global MASTER-Net observations report
  36. GRB 200903A: Swift detection of a burst
  37. GRB 200901A: MASTER OT early detection
  38. GRB 200901B: Swift-XRT refined Analysis
  39. GRB 200901B: Swift-BAT refined analysis
  40. GRB 200901A: Swift-BAT refined analysis
  41. GRB 200901B: Swift/UVOT Detection
  42. GRB 200901A: Swift/UVOT Detection
  43. GRB 200901A: Swift-XRT refined Analysis
  44. GRB 200901A: Fermi GBM observation
  45. GRB 200901B: Enhanced Swift-XRT position
  46. GRB 200829A: Swift/UVOT-XRT photometric redshift
  47. GRB 200901B: Swift detection of a burst
  48. GRB 200901A: Swift-XRT observations
  49. GRB 200901A: Swift detection of a burst
  50. Swift GRB200901.16: Global MASTER-Net observations report
  51. GRB 200829A: Fermi GBM detection
  52. GRB 200829A: Swift-BAT refined analysis
  53. Konus-Wind detection of GRB 200829A (a clone of GRB 200826B?)
  54. GRB 200829A: Swift-XRT refined Analysis
  55. GRB200829A: optical afterglow detection
  56. GRB 200829A: Global MASTER-Net OT detection
  57. GRB 200829A: AGILE/MCAL detection
  58. GRB 200829A: Enhanced Swift-XRT position
  59. GRB 200829A: Swift/UVOT Detection
  60. Swift GRB 200829A: Global MASTER-Net observations report
  61. GRB 200829A: Swift detection of a burst with an optical afterglow
  62. GRB 200826A: VLA Detection at 6 GHz
  63. GRB 200826A: Swift-XRT afterglow detection
  64. GRB200826A: Zwicky Transient Facility Identifies Optical Afterglow Candidate of a Fermi Short GRB (Trigger 620108997)
  65. GRB 200826A: Tiled Swift observations
  66. Swift Trigger 992444 is due to detector noise
  67. GRB 200819A: Swift/UVOT Upper Limits
  68. Swift GRB200821.55: Global MASTER-Net observations report
  69. Swift Trigger 992444: a possible GRB 200821A
  70. GRB 200819A: Swift-BAT refined analysis
  71. IPN triangulation of GRB 200815A (short)
  72. GRB 200819A: Swift-XRT refined Analysis
  73. GRB 200729A: Lowell Discovery Telescope observations
  74. GRB 200819A: MITSuME Akeno optical upper limits
  75. GRB 200819A / Swift J0125.7+6303: Ondrejov Perek-2m optical limit
  76. GRB 200819A: Enhanced Swift-XRT position
  77. Swift GRB 200819A: Global MASTER-Net observations report
  78. GRB 200819A: Swift detection of a burst
  79. Swift Trigger 990358 is due to detector noise
  80. Swift Trigger 989458 is due to detector noise
  81. Swift trigger 990358 is not an astrophysical source
  82. Swift GRB200816.17: Global MASTER-Net observations report
  83. Swift trigger 989458 is likely not an astrophysical source
  84. GRB 200809B: Fermi GBM detection
  85. GRB 200809B: BOOTES-3/YA optical upper limit
  86. GRB 200809B: Swift-XRT afterglow detection
  87. GRB 200809B: MAXI/GSC detection
  88. GRB 200809B: Swift ToO observations
  89. GRB 200809B: AstroSat CZTI detection
  90. GRB 200809B: Swift/BAT-GUANO detection and arcminute localization
  91. GRB 200806A: CALET Gamma-Ray Burst Monitor detection
  92. GRB 200806A: CAHA optical afterglow confirmation
  93. GRB 200806A: Swift-BAT refined analysis
  94. GRB 200806A: Swift/UVOT Possible Detection
  95. GRB 200806A: Swift-XRT refined Analysis
  96. GRB 200806A: AbAO optical upper limit
  97. GRB 200806A: AstroSat CZTI detection
  98. GRB 200806A: MITSuME Akeno optical upper limits
  99. GRB 200806A: Enhanced Swift-XRT position
  100. Swift GRB 200806A: Global MASTER-Net observations report

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