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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"

5559 results found.

  1. Fermi GRB 200919B: Global MASTER-Net observations report
  2. GRB 200916B: MASTER optical observation
  3. Fermi-GBM Sub-Threshold Detection of GRB 200917A
  4. GRB 200917A: Swift detection of a burst
  5. Fermi trigger No 621893860: Global MASTER-Net observations report
  6. IceCube Alert 200914.00: Global MASTER-Net observations report
  7. IceCube-200911A: No significant detection in HAWC
  8. IPN triangulation of GRB 200907A (short)
  9. GRB 200909B: Swift detection of a burst
  10. Fermi GRB 200909A: Global MASTER-Net observations report
  11. Fermi GRB 200907C: Global MASTER-Net observations report
  12. Fermi GRB 200906A: Global MASTER-Net observations report
  13. GRB 200906A: LBT near-infrared upper limit
  14. GRB 200906A: Nanshan/NEXT optical upper limit
  15. GRB 200903E: AstroSat CZTI detection
  16. Fermi GRB 200903C: Global MASTER-Net observations report
  17. AGILE detection of a burst (AGILE trigger no. 526185273)
  18. GRB200817B: AstroSat CZTI detection
  19. Fermi GRB 200903B: Global MASTER-Net observations report
  20. Swift GRB200903.03: Global MASTER-Net observations report
  21. GRB 200901A: MASTER OT early detection
  22. GRB 200901A: Fermi GBM observation
  23. GRB 200901A: Swift detection of a burst
  24. Swift GRB200901.16: Global MASTER-Net observations report
  25. Fermi trigger No 620402299: Global MASTER-Net observations report
  26. IPN triangulation of GRB 200826B
  27. Fermi GRB 200824A: Global MASTER-Net observations report
  28. Fermi GRB 200826A: Global MASTER-Net observations report
  29. GRB 200819A: Swift-BAT refined analysis
  30. IPN triangulation of GRB 200815A (short)
  31. GRB 200729A: Lowell Discovery Telescope observations
  32. GRB 200819A: Kitab, TSHAO optical upper limit
  33. GRB 200819A: Enhanced Swift-XRT position
  34. GRB 200819A: Swift detection of a burst
  35. Baksan Neutrino Observatory Alert 200819.09: Global MASTER-Net observations report
  36. Fermi trigger No 619270776: Global MASTER-Net observations report
  37. GRB 200806A: CAHA optical afterglow confirmation
  38. GRB 200803A: Chilescope optical upper limit
  39. GRB 200803B: MASTER possibly OT discovery
  40. GRB 200803A: AstroSat CZTI detection
  41. GRB 200803A: Fermi GBM detection
  42. Fermi GRB 200803B: Global MASTER-Net observations report
  43. GRB 200803A: Fermi-LAT detection
  44. LAT GRB200803.15: Global MASTER-Net observations report
  45. Fermi GRB 200803A: Global MASTER-Net observations report
  46. GRB 200803A: Fermi GBM Final Real-time Localization
  47. Fermi GRB 200801B: Global MASTER-Net observations report
  48. Fermi GRB 200802A: Global MASTER-Net observations report
  49. Fermi GRB 200801A: Global MASTER-Net observations report
  50. IceCube Alert 200728.35: Global MASTER-Net observations report
  51. Baksan Neutrino Observatory Alert 200726.66: Global MASTER-Net observations report
  52. Fermi GRB 200723A: Global MASTER-Net observations report
  53. Fermi GRB 200716B: Global MASTER-Net observations report
  54. Fermi GRB 200714D: Global MASTER-Net observations report
  55. Fermi GRB 200714A: Global MASTER-Net observations report
  56. GRB 200709A: Fermi GBM Final Real-time Localization
  57. GRB 200703B: AstroSat CZTI detection
  58. Fermi GRB 200702A: Global MASTER-Net observations report
  59. Trigger 980513: Swift detection of SGR Swift J1818.0-1607
  60. Fermi GRB 200626A: Global MASTER-Net observations report
  61. GRB 200623A: Fermi GBM observation
  62. IceCube-200620A: No significant detection in HAWC
  63. GRB 200623A: Swift/BAT-GUANO detection and arcminute localization of a short GRB
  64. Fermi GRB 200623A: Global MASTER-Net observations report
  65. GRB 200623A: Fermi GBM Final Real-time Localization
  66. IceCube-200620A: Upper limits from a search for additional neutrino events in IceCube
  67. IceCube-200620A: INTEGRAL was inactive at the time of the event
  68. Fermi-LAT Gamma-ray Observations of IceCube-200620A
  69. IceCube-200620A - IceCube observation of a high-energy neutrino candidate track-like event
  70. GRB 200619C: Fermi GBM Final Real-time Localization
  71. Fermi trigger No 614239407: Global MASTER-Net observations report
  72. Baksan Neutrino Observatory Alert 200617.47: Global MASTER-Net observations report
  73. Fermi GRB 200616A: Global MASTER-Net observations report
  74. GRB 200615B: MAXI/GSC detection
  75. Baksan Neutrino Observatory Alert 200614.34: Global MASTER-Net observations report
  76. Fermi GRB 200613A: Global MASTER-Net observations report
  77. Fermi GRB 200607B: Global MASTER-Net observations report
  78. Fermi GRB 200607A: Global MASTER-Net observations report
  79. Fermi trigger No 612988790: Global MASTER-Net observations report
  80. Baksan Neutrino Observatory Alert 200603.12: Global MASTER-Net observations report
  81. Fermi GRB 200601A: Global MASTER-Net observations report
  82. IceCube-200530A: No significant detection in HAWC
  83. IceCube Alert 200530.33: Global MASTER-Net observations report
  84. GRB 200529A: Swift detection of a burst
  85. GRB 200524A: CrAO optical observations
  86. Fermi GRB 200524A: Global MASTER-Net observations report
  87. ZTF Discovery of ZTF20abbiixp: The Likely Optical Afterglow to GRB 200524A
  88. GRB 200522A: LCO Optical Afterglow Detection
  89. IceCube Alert 200523.10: Global MASTER-Net observations report
  90. Fermi trigger No 611676654: Global MASTER-Net observations report
  91. Fermi trigger No 611605955: Global MASTER-Net observations report
  92. Fermi trigger No 611434353: Global MASTER-Net observations report
  93. GRB 200517A: MAXI/GSC detection
  94. Swift J1818.0-1607: BOOTES-3/YA optical upper limit
  95. Swift Detection of a burst from SGR Swift J1818.0-1607
  96. GRB 200514A: MITSuME Akeno optical upper limits
  97. GRB 200514A: MAXI/GSC detection
  98. GRB 200512A: LCO Optical Upper Limits
  99. IPN triangulation of a bright burst from SGR 1935+2154 on 2020-05-10 at 06:12 UT
  100. Insight-HXMT detection of a short bright burst from SGR 1935+2154

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