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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').

774 results found.

  1. GRB 190805B: Tiled Swift observations
  2. GRB 190804B: Swift-XRT observations
  3. GRB 190805B: MAXI/GSC detection
  4. MAXI GRB190804.33 Global MASTER-Net observations report
  5. GRB 190804B: Tiled Swift observations
  6. GRB 190804B: MAXI/GSC detection
  7. LIGO/Virgo S190728q: Coverage and upper limits from MAXI/GSC observations
  8. LIGO/Virgo S190727h: Coverage and upper limits from MAXI/GSC observations
  9. GRB 190719C: Swift/UVOT Upper Limits
  10. LIGO/Virgo S190720a: Coverage and upper limits from MAXI/GSC observations
  11. LIGO/Virgo S190718y: Coverage and upper limits from MAXI/GSC observations
  12. GRB 190714A: an X-ray flare from 2E 1624.6+1504/UCAC4 525-061488
  13. GRB 190708B: confirmation of the X-ray afterglow
  14. GRB 190714A: Tiled Swift observations
  15. GRB 190714A: MAXI/GSC detection
  16. GRB 190708B: Swift-XRT observations
  17. Konus-Wind observation of GRB 190708B
  18. GRB 190708B: Tiled Swift observations
  19. MAXI GRB190708.83 Global MASTER-Net observations report
  20. GRB 190708B: MAXI/GSC detection
  21. LIGO/Virgo S190707q: Coverage and upper limits from MAXI/GSC observations
  22. LIGO/Virgo S190706ai: Coverage and upper limits from MAXI/GSC observations
  23. GRB 190706A: MAXI/GSC detection
  24. LIGO/Virgo S190701ah: Coverage and upper limits from MAXI/GSC observations
  25. GRB 190701A: MAXI/GSC detection
  26. LIGO/Virgo S190630ag: Coverage and upper limits from MAXI/GSC observations
  27. LIGO/Virgo S190602aq: Coverage and upper limits from MAXI/GSC observations
  28. LIGO/Virgo S190521r Global MASTER-Net observations report
  29. LIGO/Virgo S190521r: Coverage and upper limits from MAXI/GSC observations
  30. IGO/Virgo S190521g: Coverage and upper limits from MAXI/GSC observations
  31. LIGO/Virgo S190519bj: MAXI/GSC Observations
  32. LIGO/Virgo S190517h: MAXI/GSC Observations
  33. LIGO/Virgo S190513bm: MAXI/GSC Observations
  34. LIGO/Virgo S190512at: MAXI/GSC Observations
  35. LIGO/Virgo S190510g: MAXI/GSC Observations
  36. LIGO/Virgo S190503bf: MAXI/GSC Observations
  37. LIGO/Virgo S190426c: MAXI/GSC Observations
  38. LIGO/Virgo S190425z: MAXI/GSC Observations
  39. LIGO/Virgo S190421ar: MAXI/GSC Observations
  40. Corrections: GRB 190404A (not 140404B ) and GRB 190404B (not 140404C)
  41. LIGO/Virgo S190412m: MAXI/GSC Observations
  42. LIGO/Virgo S190408an: MAXI/GSC Observations
  43. GRB 190404C: MITSuME Akeno and Okayama optical upper limits
  44. Konus-Wind observation of GRB 190404B
  45. CORRECTED TARGET NAME: GRB 190408A: MAXI/GSC detection
  46. GRB 140408A: MAXI/GSC detection
  47. GRB 190404C: Swift-XRT afterglow detection
  48. GRB 190404B: CALET Gamma-Ray Burst Monitor detection
  49. GRB 190404C: Swift-XRT observations
  50. GRB190404C: GROWTH-India discovery of optical counterpart
  51. GRB 190404B: Tiled Swift observations
  52. GRB 140404C: MAXI/GSC detection
  53. GRB 140404B: MAXI/GSC detection
  54. GRB190305A: MASTER Global Robotic Net optical observation
  55. GRB 190305A: Swift-XRT afterglow detection
  56. GRB 190305A: CALET Gamma-Ray Burst Monitor detection
  57. GRB 190306A: Swift-XRT observations
  58. Konus-Wind observation of GRB 190305A
  59. GRB 190306A: Tiled Swift observations
  60. GRB 190306A: MAXI/GSC detection
  61. IPN Triangulation of GRB 190305A
  62. GRB 190305A: Swift-XRT observations
  63. GRB 190305A: Insight-HXMT/HE detection
  64. GRB 190305A: MAXI/GSC detection
  65. Trigger 890732: Swift detection of MAXI J1631-479
  66. Trigger 888312: Swift detection of 4U 1901+03
  67. GRB 190204A: CALET Gamma-Ray Burst Monitor detection
  68. Konus-Wind observation of GRB 190204A
  69. GRB 190204A: AstroSat CZTI detection
  70. GRB 190204A: MAXI/GSC detection
  71. Fermi GBM trigger 570825115/190202772 is not a GRB
  72. Fermi GBM trigger 570716645/190201517 is not a GRB
  73. Fermi GBM trigger 570659556/190131856 is not a GRB
  74. GRB 190129A: CALET Gamma-Ray Burst Monitor detection
  75. GRB 190129A: Fermi GBM detection
  76. GRB 190129A: MAXI/GSC detection
  77. Trigger 886496: Another Swift trigger on MAXI J1348-630
  78. Trigger 886486: Swift detection of MAXI J1631-479
  79. Trigger 886266: Another Swift trigger on MAXI J1348-630
  80. INTEGRAL triggers from 8205 to 8211 are due to MAXI J1348-630, NOT to a GRB
  81. Swift Trigger 885960: A third Swift trigger on MAXI J1348-630
  82. Trigger 885845: A second Swift trigger on MAXI J1348-630
  83. Trigger 885807: Swift detection of MAXI J1348-630
  84. Trigger 885456: Swift detection of MAXI J1631-479
  85. Trigger 884906: Swift detection of MAXI J1631-479
  86. Trigger 882561: Swift detection of MAXI J1631-479
  87. GRB 181228A: KAIT Optical Upper Limit
  88. GRB 181222A: AstroSat CZTI detection
  89. Konus-Wind observation of GRB 181222A
  90. GRB 181222A: CALET Gamma-Ray Burst Monitor detection
  91. GRB 181222A: Fermi GBM observation
  92. GRB 181222A: MAXI/GSC detection
  93. GRB 181011A: MITSuME Akeno and Okayama optical upper limits
  94. GRB 181011A: Global MASTER Net optical inspection
  95. GRB 181011A: CALET Gamma-Ray Burst Monitor detection
  96. IPN Triangulation of GRB 181011A (long)
  97. GRB 181011A: MAXI/GSC detection
  98. Konus-Wind observation of GRB 180923A
  99. GRB 180923B - GBM Correction to GCN 23263
  100. GRB 180923A: CALET Gamma-Ray Burst Monitor detection

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