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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').

269 results found.

  1. Fermi trigger No 736197684: Global MASTER-Net observations report
  2. GRB 240303B: Fermi GBM Detection
  3. Integral GRB240115.70: Global MASTER-Net observations report
  4. Fermi trigger No 725592555: Global MASTER-Net observations report
  5. GRB 231115A: MASTER optical observations
  6. Fermi GRB 231030B: Global MASTER-Net observations report
  7. Fermi trigger No 715552087: Global MASTER-Net observations report
  8. Fermi GRB 230827A: Global MASTER-Net observations report
  9. Fermi GRB 230818A: Global MASTER-Net observations report
  10. Fermi trigger No 712927418: Global MASTER-Net observations report
  11. Fermi trigger No 711805358: Global MASTER-Net observations report
  12. Fermi trigger No 710117592: Global MASTER-Net observations report
  13. Fermi GRB 230628D: Global MASTER-Net observations report
  14. LIGO/Virgo S230622e: Global MASTER-Net observations report
  15. LIGO/Virgo S230620au: Global MASTER-Net observations report
  16. LIGO/Virgo S230616aa: Global MASTER-Net observations report
  17. Swift GRB 230618A: Global MASTER-Net observations report
  18. LIGO/Virgo S230608as: Global MASTER-Net observations report
  19. Fermi GRB 230603A: Global MASTER-Net observations report
  20. LIGO/Virgo S230529ay: Global MASTER-Net observations report
  21. LIGO/Virgo S230525a: Global MASTER-Net observations report
  22. IceCube Alert 230524.47: Global MASTER-Net observations report
  23. Fermi trigger No 706610076: Global MASTER-Net observations report
  24. LIGO/Virgo S230520ae: Global MASTER-Net observations report
  25. Fermi trigger No 704365743: Global MASTER-Net observations report
  26. GRB 230420A: MITSuME Akeno optical observation
  27. GRB 230325A: Swift/UVOT Upper Limits
  28. Integral GRB221218.34: Global MASTER-Net observations report
  29. GRB 221120A: GTC Confirmation of an Underlying Galaxy
  30. GRB220611A: Gemini Optical Afterglow Confirmation
  31. Fermi GRB 220512A: Global MASTER-Net observations report
  32. Konus-Wind detection of GRB 220403C
  33. GRB 220310C: Swift-XRT observations
  34. MAXI GRB220310.02: Global MASTER-Net observations report
  35. MAXI GRB211218.04: Global MASTER-Net observations report
  36. Fermi GRB 211130A: Global MASTER-Net observations report
  37. GRB 211105A: MASTER optical inspection
  38. GRB 211024A: MITSuME Akeno optical observation
  39. Swift trigger 1078701: MITSuME Akeno optical upper limits
  40. Fermi trigger No 654854799: Global MASTER-Net observations report
  41. Swift GRB 210919A: Global MASTER-Net observations report
  42. Swift GRB 210901A: Global MASTER-Net observations report
  43. Swift GRB210818.68: Global MASTER-Net observations report
  44. Swift GRB 210818A: Global MASTER-Net observations report
  45. Fermi GRB 210813A: Global MASTER-Net observations report
  46. Fermi GRB 210807C: Global MASTER-Net observations report
  47. Fermi trigger No 649524889: Global MASTER-Net observations report
  48. Swift GRB 210730A: Global MASTER-Net observations report
  49. Fermi trigger No 647120009: Global MASTER-Net observations report
  50. GRB 210323B: Fermi GBM observation
  51. Fermi trigger No 645047470: Global MASTER-Net observations report
  52. Swift GRB 210610B: Global MASTER-Net observations report
  53. Fermi trigger No 644155206: Global MASTER-Net observations report
  54. Swift GRB210514.71: Global MASTER-Net observations report
  55. Fermi trigger No 640695289: Global MASTER-Net observations report
  56. Swift GRB210403.35: Global MASTER-Net observations report
  57. GRB 210209A: Swift/UVOT Upper Limits
  58. GRB 210124B: AstroSat CZTI detection
  59. GRB 210104A: AROMA-N Optical Afterglow Detection
  60. GRB 201221A: Konus-Wind detection and joint Konus-Wind + Swift-BAT spectral analysis
  61. IceCube-201209A: No neutrino counterpart candidates in ANTARES search
  62. Swift GRB 201029A: Global MASTER-Net observations report
  63. SGR 1830-0645: Swift/UVOT Upper Limits
  64. Fermi trigger No 624121589: Global MASTER-Net observations report
  65. IceCube Alert 200926.33: Global MASTER-Net observations report
  66. GRB 200920B: AGILE/MCAL detection of a burst
  67. Integral GRB200914.53: Global MASTER-Net observations report
  68. Fermi GRB 200914A: Global MASTER-Net observations report
  69. IceCube Alert 200914.00: Global MASTER-Net observations report
  70. Fermi trigger No 612988790: Global MASTER-Net observations report
  71. Fermi GRB 200524A: Global MASTER-Net observations report
  72. IceCube Alert 200523.10: Global MASTER-Net observations report
  73. GRB 200502A: AstroSat CZTI detection
  74. IceCube Alert 200425.98: Global MASTER-Net observations report
  75. GRB 200205B: Swift/UVOT Detection
  76. Fermi trigger No 601677816: Global MASTER-Net observations report
  77. Fermi trigger No 601363105: Global MASTER-Net observations report
  78. LIGO/Virgo S200105ae: Global MASTER-Net observations report
  79. IceCube Alert 200101.46: Global MASTER-Net observations report
  80. Swift GRB191226.02: Global MASTER-Net observations report
  81. GRB 191123A: Swift-XRT refined Analysis
  82. GRB 191123A: Swift/UVOT detection
  83. GRB 191101A: Swift/UVOT Upper Limits
  84. GRB 191031A: COATLI Optical Observations
  85. Swift GRB191011.19: Global MASTER-Net observations report
  86. Baksan Neutrino Observatory Alert 190928.37: Global MASTER-Net observations report
  87. Integral GRB190919.99: Global MASTER-Net observations report
  88. LIGO/Virgo S190814bv: MASTER prediscovery and postdiscovery observations DECam candidate DG19wxnjc/AT2019npv field
  89. Baksan Neutrino Observatory Alert 190817.35 Global MASTER-Net observations report
  90. LIGO/Virgo S190814bv Global MASTER-Net observations report
  91. FRB 190806: MASTER optical observation
  92. Fermi trigger No 586896678 Global MASTER-Net observations report
  93. GRB 190731A: no OT detected by MASTER
  94. IceCube Alert 190712.05 Global MASTER-Net observations report
  95. Fermi trigger No 584465880 Global MASTER-Net observations report
  96. Fermi trigger No 584404689 Global MASTER-Net observations report
  97. MAXI GRB190708.83 Global MASTER-Net observations report
  98. LIGO/Virgo S190701ah: Coverage and upper limits from MAXI/GSC observations
  99. Fermi trigger No 583111521 Global MASTER-Net observations report
  100. Swift GRB190624.86 Global MASTER-Net observations report

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