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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"

12190 results found.

  1. Fermi GRB 200420A: Global MASTER-Net observations report
  2. GRB 200420A: Fermi GBM Final Real-time Localization
  3. Fermi trigger No 608935505: Global MASTER-Net observations report
  4. GRB 200412B: continued AbAO, Mondy, TSHAO, Terskol optical observations
  5. GRB 200416A: Swift/UVOT Detection
  6. GRB 200412B: Swift XRT confirmation of afterglow and UVOT upper limits
  7. GRB 200415A: Fermi-LAT localization update
  8. Konus-Wind observation of GRB 200415A (a magnetar Giant Flare in Sculptor Galaxy?)
  9. GRB 200416A: Swift-XRT refined Analysis
  10. GRB 200416A: Swift detection of a burst with an optical afterglow
  11. Fermi GRB 200415A: Global MASTER-Net observations report
  12. GRB 200415A: Fermi-LAT detection
  13. Konus-Wind observation of GRB 200412B
  14. GRB 200410A: Swift-BAT refined analysis
  15. Konus-Wind observation of GRB 200412A
  16. GRB 200412B: SAO RAS observations of OT
  17. GRB 200412B: Optical afterglow detection with 1.3m DFOT
  18. GRB 200412B: Swift-XRT afterglow detection
  19. IPN triangulation of GRB 200412A
  20. GRB 200412B: Fermi-LAT detection
  21. Konus-Wind observation of a bright burst from SGR 1935+2154
  22. Fermi-LAT Gamma-ray Observations of IceCube-200410A
  23. GRB 200411A: Swift-XRT refined Analysis
  24. GRB 200411A: Swift detection of a short burst
  25. IceCube-200410A - IceCube observation of a high-energy neutrino candidate event
  26. IceCube Alert 200410.97: Global MASTER-Net observations report
  27. SGR 1935+2154: Fermi GBM observation
  28. IPN Triangulation of a bright burst from SGR 1935+2154
  29. LIGO/Virgo S200225q: Swift XRT observations, 1 X-ray sources
  30. Konus-Wind observation of GRB 200327A
  31. LIGO/Virgo S200224ca: Swift XRT observations, 8 X-ray sources
  32. GRB 200410A: Ondrejov D50 afterglow confirmation
  33. Swift GRB200410.10: Global MASTER-Net observations report
  34. Baksan Neutrino Observatory Alert 200409.23: Global MASTER-Net observations report
  35. GRB 200409A: Swift-XRT refined Analysis
  36. GRB 200409A: Swift detection of a burst with an optical counterpart
  37. Fermi GRB 200407A: Global MASTER-Net observations report
  38. Fermi GRB 200407B: Global MASTER-Net observations report
  39. Baksan Neutrino Observatory Alert 200406.3: Global MASTER-Net observations report
  40. Fermi GRB 200403A: Global MASTER-Net observations report
  41. LIGO/Virgo S200316bj: Upper limits from Konus-Wind observations
  42. LIGO/Virgo S200311bg: Upper limits from Konus-Wind observations
  43. LIGO/Virgo S200302c: Upper limits from Konus-Wind observations
  44. LIGO/Virgo S200225q: Upper limits from Konus-Wind observations
  45. LIGO/Virgo S200224ca: Upper limits from Konus-Wind observations
  46. Fermi GRB 200402C: Global MASTER-Net observations report
  47. Fermi GRB 200402A: Global MASTER-Net observations report
  48. GRB 200325B: Optical upper limit
  49. Fermi GRB 200401A: Global MASTER-Net observations report
  50. GRB 200325B: Mondy continued observations
  51. GRB 200327A: Fermi GBM detection
  52. IPN triangulation of GRB 200327A (short)
  53. GRB 200327A: AGILE/MCAL observations
  54. GRB 200327A: Fermi GBM Final Real-time Localization
  55. GRB 200325B: Mondy, CrAO, AbAO afterglow confirmation and refined photometry of MASTER OT J111012.51+274912.8
  56. GRB 200326B: AstroSat LAXPC detection
  57. GRB 200325B: Mondy and CrAO observations, Master MASTER OT J111012.51+274912.8 confirmation
  58. Fermi trigger No 606918292: Global MASTER-Net observations report
  59. Fermi trigger No 606799116: Global MASTER-Net observations report
  60. GRB 200324A: Swift-XRT refined Analysis
  61. GRB 200324A: Tautenburg observations
  62. GRB 200324A: Swift detection of a burst
  63. Swift GRB200324.69: Global MASTER-Net observations report
  64. Fermi trigger No 606681997: Global MASTER-Net observations report
  65. LIGO/Virgo S200316bj: no counterpart candidate in SVOM/GWAC-F30 observations
  66. GRB 200320B: MAXI/GSC detection
  67. GRB 200320A: Fermi GBM Final Localization
  68. Chandra observations of GW170817 at 2.5 years since merger (All epochs 4 of 4)
  69. Fermi trigger No 606263732: Global MASTER-Net observations report
  70. LIGO/Virgo S200316bj : No significant candidates in TAROT - FRAM - GRANDMA observations.
  71. Konus-Wind observation of GRB 200313B
  72. LIGO/Virgo S200316bj: no counterpart candidate in SVOM/GWAC observations
  73. LIGO/Virgo S200316bj: No counterpart candidates in Fermi-LAT observations
  74. LIGO/Virgo S200213t: Continued Swift UVOT and XRT observations of ZTF20aamvmzj (AT2020cja)
  75. Konus-Wind observation of GRB 200313A
  76. Konus-Wind observation of GRB 200311A
  77. Fermi trigger No 606098435: Global MASTER-Net observations report
  78. LIGO/Virgo S200316bj: Coverage and upper limits from MAXI/GSC observations
  79. SGR Swift J1818.0-1607: Swift-BAT refined analysis
  80. SGR Swift J1818.0-1607: BOOTES-4/MET optical limit
  81. Fermi trigger No 605756501: Global MASTER-Net observations report
  82. Swift-BAT trigger 960986: Swift detection of a new SGR Swift J1818.0-1607
  83. Fermi trigger No 605632577: Global MASTER-Net observations report
  84. LIGO/Virgo S200311bg: No significant counterpart candidates in Fermi-LAT observations
  85. LIGO/Virgo S200311bg: Coverage and upper limits from MAXI/GSC observations
  86. GRB 200310A: MAXI/GSC detection
  87. Fermi trigger No 605309224: Global MASTER-Net observations report
  88. GRB 200306A: Swift-BAT refined analysis
  89. GRB 200306C: Swift-XRT refined Analysis
  90. GRB 200306C: VIRT optical upper limits
  91. GRB 200306A: Swift-XRT refined Analysis
  92. LIGO/Virgo S200302c: No notable candidates in GOTO imaging
  93. GRB 200306C: FRAM-ORM afterglow detection
  94. Swift GRB200306.95: Global MASTER-Net observations report
  95. GRB 200306C: Swift detection of a burst with an optical counterpart
  96. Swift GRB200306.95: Global MASTER-Net OT detection
  97. Swift GRB200306.95: Global MASTER-Net OT detection
  98. LIGO/Virgo S200302c : No significant candidates in FRAM - TAROT - GRANDMA observations.
  99. GRB 200306A: Swift detection of a burst
  100. Swift GRB200306.01: Global MASTER-Net observations report

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