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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"

19662 results found.

  1. GRB 200914A: AGILE detection
  2. GRB 200914A: Swift-XRT observations
  3. GRB 200914A: Swift ToO observations
  4. IPN triangulation of GRB 200907A (short)
  5. GRB 200909B: Swift-BAT refined analysis
  6. Swift GRB200909.97: Global MASTER-Net observations report
  7. GRB 200909B: Swift detection of a burst
  8. GRB 200907B: Swift/UVOT Upper Limits
  9. GRB 200907B: Swift-BAT refined analysis
  10. GRB 200907B: AstroSat CZTI detection
  11. GRB 200907B: Swift-XRT refined Analysis
  12. GRB 200907B: MITSuME Okayama optical upper limits
  13. Swift GRB 200907B: Global MASTER-Net observations report
  14. GRB 200907B: Enhanced Swift-XRT position
  15. Correction to GCN 28387: GRB 200907B GROWTH-India optical upper limit
  16. GRB200907A: GROWTH-India optical upper limit
  17. GRB 200907B: Prompt enhanced Swift-XRT position
  18. GRB 200907B: Swift detection of a short burst
  19. GRB 200906A: EMIR/GTC NIR upper limit
  20. GRB 200906A: LBT near-infrared upper limit
  21. GRB 200906A: Swift-BAT refined analysis
  22. GRB 200906A: Swift/UVOT Upper Limits
  23. GRB 200906A: GROWTH-India Telescope (GIT) optical r band upper limit
  24. GRB 200906A: OSN 1.5m Upper Limit
  25. GRB 200906A: Swift-XRT refined Analysis
  26. GRB 200906A: Fermi GBM detection
  27. GRB 200906A: Enhanced Swift-XRT position
  28. GRB 200906A: Swift detection of a burst
  29. Swift Triggers 994723-994725 and 994727 are not GRBs.
  30. GRB 200903A: Fermi GBM detection
  31. GRB 200903A: Swift-BAT refined analysis
  32. GRB 200903A: CALET Gamma-Ray Burst Monitor detection
  33. Swift GRB200903.03: Global MASTER-Net observations report
  34. GRB 200903A: Swift detection of a burst
  35. GRB 200901A: MASTER OT early detection
  36. GRB 200901B: Swift-XRT refined Analysis
  37. GRB 200901B: Swift-BAT refined analysis
  38. GRB 200901A: Swift-BAT refined analysis
  39. GRB 200901B: Swift/UVOT Detection
  40. GRB 200901A: Swift/UVOT Detection
  41. GRB 200901A: Swift-XRT refined Analysis
  42. GRB 200901A: Fermi GBM observation
  43. GRB 200901B: Enhanced Swift-XRT position
  44. GRB 200829A: Swift/UVOT-XRT photometric redshift
  45. GRB 200901B: Swift detection of a burst
  46. GRB 200901A: Swift-XRT observations
  47. GRB 200901A: Swift detection of a burst
  48. Swift GRB200901.16: Global MASTER-Net observations report
  49. GRB 200829A: Fermi GBM detection
  50. GRB 200829A: Swift-BAT refined analysis
  51. Konus-Wind detection of GRB 200829A (a clone of GRB 200826B?)
  52. GRB 200829A: Swift-XRT refined Analysis
  53. GRB200829A: optical afterglow detection
  54. GRB 200829A: Global MASTER-Net OT detection
  55. GRB 200829A: AGILE/MCAL detection
  56. GRB 200829A: Enhanced Swift-XRT position
  57. GRB 200829A: Swift/UVOT Detection
  58. Swift GRB 200829A: Global MASTER-Net observations report
  59. GRB 200829A: Swift detection of a burst with an optical afterglow
  60. GRB 200826A: VLA Detection at 6 GHz
  61. GRB 200826A: Swift-XRT afterglow detection
  62. GRB200826A: Zwicky Transient Facility Identifies Optical Afterglow Candidate of a Fermi Short GRB (Trigger 620108997)
  63. GRB 200826A: Tiled Swift observations
  64. Swift Trigger 992444 is due to detector noise
  65. GRB 200819A: Swift/UVOT Upper Limits
  66. Swift GRB200821.55: Global MASTER-Net observations report
  67. Swift Trigger 992444: a possible GRB 200821A
  68. GRB 200819A: Swift-BAT refined analysis
  69. IPN triangulation of GRB 200815A (short)
  70. GRB 200819A: Swift-XRT refined Analysis
  71. GRB 200729A: Lowell Discovery Telescope observations
  72. GRB 200819A: MITSuME Akeno optical upper limits
  73. GRB 200819A / Swift J0125.7+6303: Ondrejov Perek-2m optical limit
  74. GRB 200819A: Enhanced Swift-XRT position
  75. Swift GRB 200819A: Global MASTER-Net observations report
  76. GRB 200819A: Swift detection of a burst
  77. Swift Trigger 990358 is due to detector noise
  78. Swift Trigger 989458 is due to detector noise
  79. Swift trigger 990358 is not an astrophysical source
  80. Swift GRB200816.17: Global MASTER-Net observations report
  81. Swift trigger 989458 is likely not an astrophysical source
  82. GRB 200809B: Fermi GBM detection
  83. GRB 200809B: BOOTES-3/YA optical upper limit
  84. GRB 200809B: Swift-XRT afterglow detection
  85. GRB 200809B: MAXI/GSC detection
  86. GRB 200809B: Swift ToO observations
  87. GRB 200809B: AstroSat CZTI detection
  88. GRB 200809B: Swift/BAT-GUANO detection and arcminute localization
  89. GRB 200806A: CALET Gamma-Ray Burst Monitor detection
  90. GRB 200806A: CAHA optical afterglow confirmation
  91. GRB 200806A: Swift-BAT refined analysis
  92. GRB 200806A: Swift/UVOT Possible Detection
  93. GRB 200806A: Swift-XRT refined Analysis
  94. GRB 200806A: AbAO optical upper limit
  95. GRB 200806A: AstroSat CZTI detection
  96. GRB 200806A: MITSuME Akeno optical upper limits
  97. GRB 200806A: Enhanced Swift-XRT position
  98. Swift GRB 200806A: Global MASTER-Net observations report
  99. GRB 200806A: Swift detection of a burst
  100. GRB 200803A: AstroSat CZTI detection

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