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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').

559 results found.

  1. GRB 240419B: Swift-BAT refined analysis
  2. LIGO/Virgo/KAGRA S240422ed: Early X-ray Upper Limits from EP-WXT for the LVK Sky Localization Region
  3. LIGO/Virgo/KAGRA S240422ed: NOT J-band upper limit on the Swift/XRT source S240422ed_X61
  4. LIGO/Virgo/KAGRA S240422ed: WINTER J-band upper limits on the Swift/XRT source S240422ed_X61
  5. LIGO/Virgo/KAGRA S240422ed: GW-MMADS DECam upper limits on the Swift/XRT source S240422ed_X61
  6. Swift GRB 240419B: Global MASTER-Net observations report
  7. GRB 240414A: Swift-BAT refined analysis
  8. LIGO/Virgo/KAGRA S240413p: Global MASTER-Net observations report
  9. Fermi GRB 240408A: Global MASTER-Net observations report
  10. Konus-Wind detection of LXT 240402A/GRB 240402B
  11. Konus-Wind detection of GRB 240303B
  12. GRB 240222A: Swift/UVOT Upper Limits
  13. GRB 240109A: Swift-BAT refined analysis
  14. GRB 231215A: radio detection with the VLA
  15. GRB 231129A: Swift-BAT refined analysis
  16. GRB 231129A: BOOTES-5/JGT optical upper limit
  17. GRB 231118A: Swift-BAT refined analysis
  18. GRB 231111A: Swift-BAT refined analysis
  19. LIGO/Virgo/KAGRA S231029ai: Global MASTER-Net observations report
  20. IceCube Alert 231027.18: Global MASTER-Net observations report
  21. GRB 230919A: AstroSat CZTI detection
  22. GRB 230911C: Swift-BAT refined analysis
  23. GRB 230826A: Swift-BAT refined analysis
  24. GRB 230827A: Swift/BAT-GUANO detection of a burst outside the coded FOV
  25. Fermi GRB 230827A: Global MASTER-Net observations report
  26. Swift GRB230825.75: Global MASTER-Net observations report
  27. Fermi GRB 230814A: Global MASTER-Net observations report
  28. Swift GRB230728.12: Global MASTER-Net observations report
  29. Fermi-LAT gamma-ray observations of IceCube-230725A
  30. IceCube-230725A - IceCube observation of a high-energy neutrino candidate track-like event
  31. LIGO/Virgo S230622e: Global MASTER-Net observations report
  32. LIGO/Virgo S230615be: Global MASTER-Net observations report
  33. LIGO/Virgo/KAGRA S230518h: GECKO tiling observations with KMTNet
  34. GRB 230430A: AstroSat CZTI detection
  35. IPN triangulation of GRB 230418A (short)
  36. Fermi GRB 230402A: Global MASTER-Net observations report
  37. Fermi GRB 230227A: Global MASTER-Net observations report
  38. Fermi GRB 230215A: Global MASTER-Net observations report
  39. GRB 221231A: Fermi GBM Observation
  40. GRB 230101A: AstroSat CZTI detection
  41. Fermi GRB 221223A: Global MASTER-Net observations report
  42. GRB 221216A: Swift-XRT refined Analysis
  43. Fermi trigger No 687190301: Global MASTER-Net observations report
  44. GRB 220831A: ATCA 5/9 GHz radio observations
  45. GRB 220711B: Fermi GBM Detection
  46. GRB 220624A: Fermi GBM Detection
  47. Fermi GRB 220623B: Global MASTER-Net observations report
  48. GRB 220623A: Swift-XRT observations
  49. Konus-Wind detection of an intermediate flare from SGR 1935+2154 on June 16
  50. Swift GRB220521.97: Global MASTER-Net observations report
  51. GRB 220514B: MAXI/GSC detection
  52. Fermi-LAT Gamma-ray Observations of IceCube-220509A
  53. MAXI GRB220506.27: Global MASTER-Net observations report
  54. IceCube Alert 220501.95: Global MASTER-Net observations report
  55. GRB 220319A: Mondy optical uper limit
  56. GRB 220315A: MASTER Global Robotic Net optical observations
  57. Konus-Wind detection of GRB 220310A
  58. Fermi trigger No 668410535: Global MASTER-Net observations report
  59. Swift GRB 220306B: Global MASTER-Net observations report
  60. Konus-Wind observation of GRB 220219B
  61. GRB 220210A: BOOTES-5/JGT optical afterglow candidate
  62. GRB 220130A: Fermi GBM Observation
  63. Konus-Wind detection of GRB 220107A
  64. Konus-Wind detection of GRB 210928A
  65. Swift GRB 210919A: Global MASTER-Net observations report
  66. Konus-Wind detection of GRB 210905A
  67. Integral GRB210829.17: Global MASTER-Net observations report
  68. Integral GRB210829.14: Global MASTER-Net observations report
  69. GRB 210807C: Fermi GBM detection
  70. Konus-Wind detection of GRB 210702A
  71. Fermi trigger No 646194855: Global MASTER-Net observations report
  72. Swift GRB210618.07: Global MASTER-Net observations report
  73. Swift Detection of probable new Swift SGR J1555.2-5402
  74. Fermi GRB 210528A: Global MASTER-Net observations report
  75. GRB 210521A: MAXI/GSC detection
  76. GRB 210514A: update on the BAT trigger time and burst duration
  77. Swift Trigger 1045571 is not a GRB
  78. GRB 210419A: Swift-BAT refined analysis
  79. GRB 210410A: Swift-XRT refined Analysis
  80. Fermi trigger No 639199407: Global MASTER-Net observations report
  81. GRB 210403A: Swift-BAT refined analysis
  82. GRB 210318B: Swift-BAT refined analysis
  83. GRB 210204A: AstroSat CZTI Detection
  84. Fermi GRB 210120A: Global MASTER-Net observations report
  85. Fermi trigger No 631602681: Global MASTER-Net observations report
  86. GRB 210104A: GWAC-F60A optical afterglow observations
  87. GRB 201223A: Swift/UVOT Detection
  88. Konus-Wind detection of GRB 201216C
  89. Trigger 1007266: Swift detection of 1A 0535+262
  90. Swift Trigger 1006917 is Be/X-ray binary pulsar 1A 0535+262
  91. IceCube Alert 201014.09: Global MASTER-Net observations report
  92. GRB 201004A: Fermi GBM Final Localization
  93. Fermi trigger No 622618714: Global MASTER-Net observations report
  94. IPN triangulation of GRB 200916B (short)
  95. GRB 200903A: Fermi GBM detection
  96. Swift Trigger 992444 is due to detector noise
  97. Swift Trigger 990358 is due to detector noise
  98. Swift Trigger 989458 is due to detector noise
  99. Fermi GRB 200723A: Global MASTER-Net observations report
  100. GRB 200630A: Swift-BAT refined analysis

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