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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. 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"

3758 results found.

  1. GRB 201227A: GRAWITA VST-ESO PARANAL observations
  2. GRB 201227A: Swift-XRT observations
  3. Konus-Wind observation of GRB 201227A
  4. Baksan Neutrino Observatory Alert 201228.36: Global MASTER-Net observations report
  5. Fermi GRB 201228B: Global MASTER-Net observations report
  6. GRB 201228B: Fermi GBM Final Real-time Localization
  7. GRB 201228A: Fermi GBM Final Real-time Localization
  8. Fermi trigger No 630389391: Global MASTER-Net observations report
  9. Fermi GRB 201222B: Global MASTER-Net observations report
  10. GRB 201221D: Lowell Discovery Telescope afterglow observations
  11. GRB 201221E: Fermi GBM Final Real-time Localization
  12. Fermi GBM Sub-Threshold Detection of GRB 201221A
  13. Konus-Wind detection of GRB 201216C
  14. Baksan Neutrino Observatory Alert 201216.94: Global MASTER-Net observations report
  15. Fermi GRB 201216A: Global MASTER-Net observations report
  16. GRB 201215A: BALROG localization (Fermi Trigger 629706213 / GRB 201215266)
  17. GRB 201215A: Fermi GBM Final Real-time Localization
  18. Integral GRB201214.26: Global MASTER-Net observations report
  19. GRB 201208A: LCO observations
  20. GRB201130A: Zwicky Transient Facility Follow-Up of a Fermi Short GRB (Trigger 628407054)
  21. GRB 201128B: Swift/BAT-GUANO detection and arcminute localization
  22. IceCube Alert 201130.85: Global MASTER-Net observations report
  23. GRB 201130A: DDOTI Observations
  24. Fermi trigger No 628278856: Global MASTER-Net observations report
  25. GRB 201128A: DDOTI Observations
  26. GRB 200826A: TNG and LBT constraints on a supernova bump
  27. Fermi GRB 201121A: Global MASTER-Net observations report
  28. Fermi GRB 201120B: Global MASTER-Net observations report
  29. INTEGRAL Weak#8825: AROMA-N Optical Observation
  30. Konus-Wind detection of GRB 201116A
  31. Fermi trigger No 627198169: Global MASTER-Net observations report
  32. GRB 201114A: AstroSat CZTI detection
  33. GRB 201108A: Fermi GBM Final Real-time Localization
  34. ZTF20acozryr/AT2020yxz (GRB 201103B): Assy optical observations
  35. GRB 201104B: Kitab optical observations
  36. GRB 201103B (ZTF20acozryr/AT2020yxz): Nanshan/NEXT-0.6m optical observations
  37. ZTF20acozryr/AT2020yxz: Zwicky Transient Facility discovery of a fast optical transient with no associated GRB
  38. GRB 201029A: Swift-BAT refined analysis
  39. GRB 201024A: Redshift from GTC/OSIRIS
  40. Swift GRB201024.12: Global MASTER-Net observations report
  41. GRB 201020B: Nanshan/NEXT optical afterglow confirmation
  42. GRB 201020A: DOAO optical afterglow observations
  43. GRB 201020A: MITSuME Akeno optical observation
  44. IceCube-201014A: No significant detection in HAWC
  45. Fermi GRB 201016B: Global MASTER-Net observations report
  46. Fermi GRB 201007A: Global MASTER-Net observations report
  47. Baksan Neutrino Observatory Alert 201006.88: Global MASTER-Net observations report
  48. Fermi trigger No 623470566: Global MASTER-Net observations report
  49. Fermi trigger No 623493962: Global MASTER-Net observations report
  50. IceCube-200926A: JCMT/SCUBA2 observations
  51. IceCube-200929A: Upper limits from a search for additional neutrino events in IceCube
  52. GRB 200928B: AstroSat CZTI detection
  53. GRB 200928B: BALROG localization (Fermi Trigger 622991684 / GRB 200928552)
  54. GRB 200928B: Fermi GBM Final Real-time Localization
  55. GRB 200928A: Fermi GBM Final Localization
  56. Fermi GRB 200925A: Global MASTER-Net observations report
  57. Fermi GRB 200924A: Global MASTER-Net observations report
  58. GRB 200924B: Fermi GBM Final Localization
  59. Fermi trigger No 622618714: Global MASTER-Net observations report
  60. Fermi GRB 200923A: Global MASTER-Net observations report
  61. Fermi GRB 200922B: Global MASTER-Net observations report
  62. Fermi-GBM Sub-Threshold Detection of GRB 200917A
  63. GRB 200917A: Swift detection of a burst
  64. GRB 200916A: Fermi GBM Final Real-time Localization
  65. Fermi GRB 200914A: Global MASTER-Net observations report
  66. IceCube Alert 200914.00: Global MASTER-Net observations report
  67. Swift GRB200909.97: Global MASTER-Net observations report
  68. Fermi GRB 200907C: Global MASTER-Net observations report
  69. GRB 200907C: Fermi GBM Final Real-time Localization
  70. Fermi GRB 200906A: Global MASTER-Net observations report
  71. IPN triangulation of GRB 200903E
  72. Fermi GRB 200903B: Global MASTER-Net observations report
  73. GRB 200829A: Continued Nanshan/NEXT optical observations
  74. GRB 200826A
  75. Fermi trigger No 620402299: Global MASTER-Net observations report
  76. IPN triangulation of GRB 200826B
  77. Swift Trigger 992444: a possible GRB 200821A
  78. Fermi trigger No 619270776: Global MASTER-Net observations report
  79. IceCube200806A: No significant detection in HAWC
  80. GRB 200809B: MAXI/GSC detection
  81. GRB 200806A: CALET Gamma-Ray Burst Monitor detection
  82. IPN triangulation of GRB 200805A (short)
  83. Swift GRB 200806A: Global MASTER-Net observations report
  84. GRB 200806A: Swift detection of a burst
  85. Fermi GRB 200802A: Global MASTER-Net observations report
  86. GRB 200729A: IceCube neutrino search
  87. GRB 200729A: TNG NIR upper limits
  88. IceCube GCN Notice 134327_10548129 retraction
  89. Baksan Neutrino Observatory Alert 200726.66: Global MASTER-Net observations report
  90. GRB 200723A: GOTO candidate afterglow and host galaxy
  91. IPN triangulation of GRB 200716A
  92. GRB 200716B: BALROG localization (Fermi Trigger 616577673 / GRB 200716316)
  93. GRB 200716B: Fermi GBM Final Real-time Localization
  94. GRB 200714E: Fermi GBM observation
  95. Fermi GRB 200714D: Global MASTER-Net observations report
  96. Fermi GRB 200714A: Global MASTER-Net observations report
  97. GRB 200714C: Fermi GBM Final Real-time Localization
  98. Fermi-LAT-ANTARES 200407a Coincidence
  99. Trigger 980513: Swift detection of SGR Swift J1818.0-1607
  100. GRB 200629A: AstroSat CZTI detection

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