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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"

11854 results found.

  1. GRB 200412B: Swift-XRT afterglow detection
  2. IPN triangulation of GRB 200412A
  3. GRB 200412B: Fermi-LAT detection
  4. Konus-Wind observation of a bright burst from SGR 1935+2154
  5. Fermi-LAT Gamma-ray Observations of IceCube-200410A
  6. GRB 200411A: Swift-XRT refined Analysis
  7. GRB 200411A: Swift detection of a short burst
  8. IceCube-200410A - IceCube observation of a high-energy neutrino candidate event
  9. IceCube Alert 200410.97: Global MASTER-Net observations report
  10. LIGO/Virgo S200225q: Swift XRT observations, 1 X-ray sources
  11. Konus-Wind observation of GRB 200327A
  12. LIGO/Virgo S200224ca: Swift XRT observations, 8 X-ray sources
  13. GRB 200410A: Ondrejov D50 afterglow confirmation
  14. Swift GRB200410.10: Global MASTER-Net observations report
  15. Baksan Neutrino Observatory Alert 200409.23: Global MASTER-Net observations report
  16. GRB 200409A: Swift-XRT refined Analysis
  17. GRB 200409A: Swift detection of a burst with an optical counterpart
  18. Fermi GRB 200407A: Global MASTER-Net observations report
  19. Fermi GRB 200407B: Global MASTER-Net observations report
  20. Baksan Neutrino Observatory Alert 200406.3: Global MASTER-Net observations report
  21. Fermi GRB 200403A: Global MASTER-Net observations report
  22. LIGO/Virgo S200316bj: Upper limits from Konus-Wind observations
  23. LIGO/Virgo S200311bg: Upper limits from Konus-Wind observations
  24. LIGO/Virgo S200302c: Upper limits from Konus-Wind observations
  25. LIGO/Virgo S200225q: Upper limits from Konus-Wind observations
  26. LIGO/Virgo S200224ca: Upper limits from Konus-Wind observations
  27. Fermi GRB 200402C: Global MASTER-Net observations report
  28. Fermi GRB 200402A: Global MASTER-Net observations report
  29. GRB 200325B: Optical upper limit
  30. Fermi GRB 200401A: Global MASTER-Net observations report
  31. GRB 200325B: Mondy continued observations
  32. GRB 200327A: Fermi GBM detection
  33. IPN triangulation of GRB 200327A (short)
  34. GRB 200327A: AGILE/MCAL observations
  35. GRB 200327A: Fermi GBM Final Real-time Localization
  36. GRB 200325B: Mondy, CrAO, AbAO afterglow confirmation and refined photometry of MASTER OT J111012.51+274912.8
  37. GRB 200326B: AstroSat LAXPC detection
  38. GRB 200325B: Mondy and CrAO observations, Master MASTER OT J111012.51+274912.8 confirmation
  39. Fermi trigger No 606918292: Global MASTER-Net observations report
  40. Fermi trigger No 606799116: Global MASTER-Net observations report
  41. GRB 200324A: Swift-XRT refined Analysis
  42. GRB 200324A: Tautenburg observations
  43. GRB 200324A: Swift detection of a burst
  44. Swift GRB200324.69: Global MASTER-Net observations report
  45. Fermi trigger No 606681997: Global MASTER-Net observations report
  46. LIGO/Virgo S200316bj: no counterpart candidate in SVOM/GWAC-F30 observations
  47. GRB 200320B: MAXI/GSC detection
  48. GRB 200320A: Fermi GBM Final Localization
  49. Chandra observations of GW170817 at 2.5 years since merger (All epochs 4 of 4)
  50. Fermi trigger No 606263732: Global MASTER-Net observations report
  51. LIGO/Virgo S200316bj : No significant candidates in TAROT - FRAM - GRANDMA observations.
  52. Konus-Wind observation of GRB 200313B
  53. LIGO/Virgo S200316bj: no counterpart candidate in SVOM/GWAC observations
  54. LIGO/Virgo S200316bj: No counterpart candidates in Fermi-LAT observations
  55. LIGO/Virgo S200213t: Continued Swift UVOT and XRT observations of ZTF20aamvmzj (AT2020cja)
  56. Konus-Wind observation of GRB 200313A
  57. Konus-Wind observation of GRB 200311A
  58. Fermi trigger No 606098435: Global MASTER-Net observations report
  59. LIGO/Virgo S200316bj: Coverage and upper limits from MAXI/GSC observations
  60. Fermi trigger No 605756501: Global MASTER-Net observations report
  61. Fermi trigger No 605632577: Global MASTER-Net observations report
  62. LIGO/Virgo S200311bg: No significant counterpart candidates in Fermi-LAT observations
  63. LIGO/Virgo S200311bg: Coverage and upper limits from MAXI/GSC observations
  64. GRB 200310A: MAXI/GSC detection
  65. Fermi trigger No 605309224: Global MASTER-Net observations report
  66. GRB 200306A: Swift-BAT refined analysis
  67. GRB 200306C: Swift-XRT refined Analysis
  68. GRB 200306C: VIRT optical upper limits
  69. GRB 200306A: Swift-XRT refined Analysis
  70. LIGO/Virgo S200302c: No notable candidates in GOTO imaging
  71. GRB 200306C: FRAM-ORM afterglow detection
  72. Swift GRB200306.95: Global MASTER-Net observations report
  73. GRB 200306C: Swift detection of a burst with an optical counterpart
  74. Swift GRB200306.95: Global MASTER-Net OT detection
  75. Swift GRB200306.95: Global MASTER-Net OT detection
  76. LIGO/Virgo S200302c : No significant candidates in FRAM - TAROT - GRANDMA observations.
  77. GRB 200306A: Swift detection of a burst
  78. Swift GRB200306.01: Global MASTER-Net observations report
  79. GRB 200228B: continued optical observations
  80. Konus-Wind observation of GRB200303A
  81. LIGO/Virgo S200302c: AstroSat CZTI upper limits
  82. GRB 200303A: Swift-XRT refined Analysis
  83. Swift GRB200303.11: Global MASTER-Net observations report
  84. Fermi trigger No 604895668: Global MASTER-Net observations report
  85. LIGO/Virgo S200302c: No significant counterpart candidates in Fermi-LAT observations
  86. LIGO/Virgo S200302c: No counterpart candidates in KAIT observations
  87. LIGO/Virgo S200302c: No counterpart candidates in HAWC observations
  88. LIGO/Virgo S200225q: AstroSat CZTI upper limits
  89. LIGO/Virgo S200219ac: AstroSat CZTI upper limits
  90. LIGO/Virgo S200302c: Coverage and upper limits from MAXI/GSC observations
  91. LIGO/Virgo S200225q : No significant candidates in TAROT - FRAM - GRANDMA observations.
  92. GRB 200228B: Swift-XRT refined Analysis
  93. GRB 200228B: KAIT Optical Upper Limit
  94. Fermi-LAT Gamma-ray Observations of IceCube-200227A
  95. GRB 200227A: Insight-HXMT/HE detection
  96. GRB 200227A: Fermi GBM observation
  97. LIGO/Virgo S200224ca : No significant candidates in TAROT - FRAM - GRANDMA observations
  98. IceCube-200227A: IceCube observation of a high-energy neutrino candidate event
  99. GRB 200227A: Swift detection of a burst
  100. GRB 200227A: Fermi GBM Final Real-time Localization

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