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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"

21113 results found.

  1. GRB 200424A: Swift-XRT observations
  2. GRB 200424A: Swift ToO observations
  3. Fermi GRB 200423A: Global MASTER-Net observations report
  4. GRB 200415A correction to GCN 27627 (possible magnetar Giant Flare in Sculptor Galaxy): INTEGRAL observations
  5. GRB 200422A: MASTER optical observations
  6. GRB 200415A (possible magnetar Giant Flare in Sculptor Galaxy): INTEGRAL observations
  7. GRB 200410A: Liverpool Telescope First Hour Observations
  8. Fermi-LAT Gamma-ray Observations of IceCube-200421A
  9. Fermi GRB 200421A: Global MASTER-Net observations report
  10. IceCube-200421A: not observable by Fermi-GBM
  11. IceCube Alert 200421.02: Global MASTER-Net observations report
  12. IceCube Alert 200420.97: Global MASTER-Net observations report
  13. GRB 200412B: continued Mondy and Terskol optical observations
  14. Fermi GRB 200420A: Global MASTER-Net observations report
  15. Fermi trigger No 608935505: Global MASTER-Net observations report
  16. GRB 200412B: continued Terskol optical observations
  17. GRB 200412B: continued AbAO, Mondy, TSHAO, Terskol optical observations
  18. GRB 200416A: Swift/UVOT Detection
  19. GRB 200412B: Swift XRT confirmation of afterglow and UVOT upper limits
  20. GRB 200415A: MASTER imspection and possible localisation
  21. GRB200412B: GROWTH India detection of afterglow
  22. GRB 200416A: Swift-XRT refined Analysis
  23. GRB 200412B: continued Tautenburg observations
  24. Fermi GRB 200415A: Global MASTER-Net observations report
  25. GRB 200411A: Chandra observations indicative of temporal steepening
  26. GRB 200412B: Mondy optical observations
  27. GRB 200412B: continued Tautenburg observations
  28. GRB 200412B: Tautenburg observations
  29. GRB 200412B: contunued AbAO optical observations
  30. GRB 200411A: ATCA 5/9 GHz radio observations
  31. GRB 200412B: Xinglong TNT optical observations
  32. GRB 200412B: SAO RAS observations of OT
  33. GRB 200405B: Further Swift-XRT observations
  34. GRB 200412B: Tautenburg observations
  35. GRB 200412B: AbAO optical observations
  36. IceCube-200410A : Upper limits from Insight-HXMT/HE observations
  37. GRB 200412B: Swift-XRT afterglow detection
  38. Fermi GRB 200412A: Global MASTER-Net observations report
  39. GRB 200412B: MASTER-Amur Optical Couterpart in Gagarin day!
  40. GRB 200412B: MASTER Optical Couterpart in Gagarin day!
  41. Correction to GCN 27551 - Swift is observing GRB 200412*B*
  42. GRB 200412B: Tiled Swift observations
  43. Fermi GRB 200412B: Global MASTER-Net observations report
  44. Fermi-LAT Gamma-ray Observations of IceCube-200410A
  45. Swift GRB 200411A: Global MASTER-Net observations report
  46. IceCube-200410A: Upper limits from Fermi-GBM Observations
  47. GRB 200411A: Swift/UVOT Upper Limits
  48. IceCube Alert 200410.97: Global MASTER-Net observations report
  49. GRB 200410A: Swift/UVOT Detection
  50. Baksan Neutrino Observatory Alert 200410.82: Global MASTER-Net observations report
  51. Fermi trigger No 608204639: Global MASTER-Net observations report
  52. Baksan Neutrino Observatory Alert 200409.81: Global MASTER-Net observations report
  53. LIGO/Virgo S200225q: Swift XRT observations, 1 X-ray sources
  54. LIGO/Virgo S200224ca: Swift XRT observations, 8 X-ray sources
  55. GRB 200409A: No detection of radio emission 5 hours post-burst
  56. Swift GRB200410.10: Global MASTER-Net observations report
  57. GRB 200405B: ATCA follow-up and ASKAP limits on pre-burst radio emission
  58. Baksan Neutrino Observatory Alert 200408.26: Global MASTER-Net observations report
  59. Baksan Neutrino Observatory Alert 200409.23: Global MASTER-Net observations report
  60. Swift GRB 200409A: Global MASTER-Net observations report
  61. Fermi GRB 200407A: Global MASTER-Net observations report
  62. Fermi GRB 200407B: Global MASTER-Net observations report
  63. Baksan Neutrino Observatory Alert 200406.3: Global MASTER-Net observations report
  64. GRB 200405B: Swift-XRT observations
  65. GRB 200405B: Swift ToO observations
  66. Fermi GRB 200405A: Global MASTER-Net observations report
  67. GRB 200405B: Swift/BAT-GUANO detection and *possible* arcminute localization of a short GRB
  68. Fermi GRB 200403C: Global MASTER-Net observations report
  69. Fermi GRB 200403B: Global MASTER-Net observations report
  70. Fermi GRB 200403A: Global MASTER-Net observations report
  71. LIGO/Virgo S200316bj: Upper limits from Konus-Wind observations
  72. LIGO/Virgo S200311bg: Upper limits from Konus-Wind observations
  73. LIGO/Virgo S200302c: Upper limits from Konus-Wind observations
  74. LIGO/Virgo S200225q: Upper limits from Konus-Wind observations
  75. LIGO/Virgo S200224ca: Upper limits from Konus-Wind observations
  76. GRB 200325B: Mondy continued observations
  77. Fermi GRB 200402C: Global MASTER-Net observations report
  78. Fermi trigger No 607537834: Global MASTER-Net observations report
  79. Fermi GRB 200402A: Global MASTER-Net observations report
  80. GRB 200325B: further Swift-XRT observations
  81. Fermi GRB 200401A: Global MASTER-Net observations report
  82. GRB 200325B: Mondy continued observations
  83. GRB 200325B: Mondy continued observations
  84. GRB 200325B: Mondy continued observations
  85. GRB 200325B: Tautenburg observations
  86. GRB 200327A: AGILE/MCAL observations
  87. Fermi trigger No 607035413: Global MASTER-Net observations report
  88. GRB 200325B: Swift-XRT and UVOT observations
  89. GRB 200325B: Mondy and CrAO observations, Master MASTER OT J111012.51+274912.8 confirmation
  90. Fermi trigger No 606918292: Global MASTER-Net observations report
  91. GRB 200325B: Swift ToO observations
  92. Fermi trigger No 606799116: Global MASTER-Net observations report
  93. GRB 200325B: MASTERt OT detection
  94. Fermi trigger No 606840801: Global MASTER-Net observations report
  95. GRB 200324A: Swift/UVOT Upper Limits
  96. GRB 200325A: AGILE/MCAL observations
  97. GRB 200324A: Tautenburg observations
  98. Swift GRB200324.69: Global MASTER-Net observations report
  99. Fermi trigger No 606681997: Global MASTER-Net observations report
  100. LIGO/Virgo S200316bj: no counterpart candidate in SVOM/GWAC-F30 observations

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