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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"
  1. GRB 200412B: continued Terskol optical observations
  2. GRB 200412B: continued AbAO, Mondy, TSHAO, Terskol optical observations
  3. GRB 200410A: Optical upper limit
  4. GRB 200416A: Swift/UVOT Detection
  5. GRB 200416A: Swift-BAT refined analysis
  6. GRB 200412B: Swift XRT confirmation of afterglow and UVOT upper limits
  7. GRB 200415A: MASTER imspection and possible localisation
  8. GRB200412B: GROWTH India detection of afterglow
  9. GRB 200415A: Fermi-LAT localization update
  10. Konus-Wind observation of GRB 200415A (a magnetar Giant Flare in Sculptor Galaxy?)
  11. Improved IPN error box for GRB 200415A (consistent with the Sculptor Galaxy)
  12. GRB 200416A: Swift-XRT refined Analysis
  13. GRB 200412B: continued Tautenburg observations
  14. GRB 200416A: Fermi GBM observation
  15. GRB 200416A: Swift detection of a burst with an optical afterglow
  16. Fermi GRB 200415A: Global MASTER-Net observations report
  17. GRB 200411A: Chandra observations indicative of temporal steepening
  18. GRB 200412A : AstroSat CZTI detection
  19. GRB 200415A: Fermi GBM observation
  20. GRB 200415A: Fermi-LAT detection
  21. IPN triangulation of GRB 200415A (possible Magnetar Giant Flare in Sculptor Galaxy?)
  22. GRB 200410A: CALET Gamma-Ray Burst Monitor detection
  23. GRB 200412B: Mondy optical observations
  24. GRB 200412B: continued Tautenburg observations
  25. Konus-Wind observation of GRB 200412B
  26. GRB 200415A: BALROG localization (Fermi Trigger 608633290 / GRB 200415367)
  27. GRB 200415A: Fermi GBM Final Real-time Localization
  28. GRB 200410A: Swift-BAT refined analysis
  29. Konus-Wind observation of GRB 200412A
  30. GRB 200412B: MITSuME Akeno optical observation
  31. GRB 200412B: Tautenburg observations
  32. GRB 200412B: contunued AbAO optical observations
  33. GRB 200411A: ATCA 5/9 GHz radio observations
  34. GRB 200412B: CALET Gamma-Ray Burst Monitor detection
  35. GRB 200412B: Xinglong TNT optical observations
  36. GRB 200412B: SAO RAS observations of OT
  37. IceCube-200410A: No significant detection in HAWC
  38. GRB 200405B: Further Swift-XRT observations
  39. GRB 200412B: Tautenburg observations
  40. GRB 200412B: AbAO optical observations
  41. GRB 200412B: Insight-HXMT/HE detection
  42. GRB 200412B: Optical afterglow detection with 1.3m DFOT
  43. GRB 200412B : AstroSat CZTI detection
  44. IceCube-200410A : Upper limits from Insight-HXMT/HE observations
  45. GRB 200412B: Swift-XRT afterglow detection
  46. IPN triangulation of GRB 200412A
  47. Fermi GRB 200412A: Global MASTER-Net observations report
  48. GRB 200412B: Fermi GBM detection
  49. GRB 200412B: Fermi-LAT detection
  50. GRB 200412B: MASTER-Amur Optical Couterpart in Gagarin day!
  51. GRB 200412B: MASTER Optical Couterpart in Gagarin day!
  52. Konus-Wind observation of a bright burst from SGR 1935+2154
  53. Correction to GCN 27551 - Swift is observing GRB 200412*B*
  54. IceCube-200410A: Upper limits from a search for additional neutrino events in IceCube
  55. GRB 200412B: Tiled Swift observations
  56. GRB 200412A: Fermi GBM detection
  57. Fermi GRB 200412B: Global MASTER-Net observations report
  58. GRB 200412B: BALROG localization (Fermi Trigger 608375325 / GRB 200412381)
  59. GRB 200412B: Fermi GBM Final Real-time Localization
  60. GRB 200412A: BALROG localization (Fermi Trigger 608367436 / GRB 200412290)
  61. GRB 200411A: Swift-BAT refined analysis
  62. Fermi-LAT Gamma-ray Observations of IceCube-200410A
  63. GRB 200411A: Fermi GBM observation
  64. Swift GRB 200411A: Global MASTER-Net observations report
  65. IceCube-200410A: Upper limits from Fermi-GBM Observations
  66. GRB 200411A: Swift-XRT refined Analysis
  67. GRB 200411A: Swift/UVOT Upper Limits
  68. GRB 200411A: Enhanced Swift-XRT position
  69. IceCube-200410A: Possible associated excess in INTEGRAL SPI-ACS prompt observation
  70. GRB 200411A: Swift detection of a short burst
  71. GRB 200411A: Fermi GBM Final Real-time Localization
  72. IceCube-200410A - IceCube observation of a high-energy neutrino candidate event
  73. IceCube Alert 200410.97: Global MASTER-Net observations report
  74. GRB 200410A: Swift/UVOT Detection
  75. SGR 1935+2154: Fermi GBM observation
  76. Baksan Neutrino Observatory Alert 200410.82: Global MASTER-Net observations report
  77. Fermi trigger No 608204639: Global MASTER-Net observations report
  78. Baksan Neutrino Observatory Alert 200409.81: Global MASTER-Net observations report
  79. IPN Triangulation of a bright burst from SGR 1935+2154
  80. LIGO/Virgo S200225q: Swift XRT observations, 1 X-ray sources
  81. Konus-Wind observation of GRB 200327A
  82. LIGO/Virgo S200224ca: Swift XRT observations, 8 X-ray sources
  83. GRB 200410A: Swift-XRT refined Analysis
  84. GRB 200410A: Enhanced Swift-XRT position
  85. GRB 200409A: No detection of radio emission 5 hours post-burst
  86. GRB 200410A: Ondrejov D50 afterglow confirmation
  87. GRB 200409A: Swift-BAT refined analysis
  88. GRB 200410A: Swift detection of a burst with a possible optical counterpart
  89. Swift GRB200410.10: Global MASTER-Net observations report
  90. GRB 200405B: ATCA follow-up and ASKAP limits on pre-burst radio emission
  91. Baksan Neutrino Observatory Alert 200408.26: Global MASTER-Net observations report
  92. Fermi GBM Sub-Threshold Detection of GRB 200409A
  93. Baksan Neutrino Observatory Alert 200409.23: Global MASTER-Net observations report
  94. Swift GRB 200409A: Global MASTER-Net observations report
  95. GRB 200409A: Swift-XRT refined Analysis
  96. GRB 200409A: Enhanced Swift-XRT position
  97. GRB 200409A: Swift detection of a burst with an optical counterpart
  98. Fermi GRB 200407A: Global MASTER-Net observations report
  99. Fermi GRB 200407B: Global MASTER-Net observations report
  100. IPN triangulation of GRB 200407A (short)

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