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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').
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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.

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subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

645 results found.

  1. LIGO/Virgo/KAGRA S240413p: Global MASTER-Net observations report
  2. Swift Trigger 1220736: detection of 4U 1543-62.
  3. Fermi GRB 240408A: Global MASTER-Net observations report
  4. Konus-Wind detection of LXT 240402A/GRB 240402B
  5. Konus-Wind detection of GRB 240303B
  6. GRB 240109A: Swift-BAT refined analysis
  7. GRB 231215A: radio detection with the VLA
  8. GRB 231129A: Swift-BAT refined analysis
  9. GRB 231129A: BOOTES-5/JGT optical upper limit
  10. GRB 231118A: Swift-BAT refined analysis
  11. GRB 231111A: Swift-BAT refined analysis
  12. LIGO/Virgo/KAGRA S231029ai: Global MASTER-Net observations report
  13. IceCube Alert 231027.18: Global MASTER-Net observations report
  14. GRB 230911C: Swift-BAT refined analysis
  15. GRB 230826A: Swift-BAT refined analysis
  16. GRB 230827A: Swift/BAT-GUANO detection of a burst outside the coded FOV
  17. Fermi GRB 230827A: Global MASTER-Net observations report
  18. Swift GRB230825.75: Global MASTER-Net observations report
  19. Fermi GRB 230814A: Global MASTER-Net observations report
  20. Swift GRB230728.12: Global MASTER-Net observations report
  21. LIGO/Virgo S230622e: Global MASTER-Net observations report
  22. LIGO/Virgo S230615be: Global MASTER-Net observations report
  23. LIGO/Virgo/KAGRA S230518h: GECKO tiling observations with KMTNet
  24. GRB 230430A: AstroSat CZTI detection
  25. IPN triangulation of GRB 230418A (short)
  26. Fermi GRB 230402A: Global MASTER-Net observations report
  27. Trigger 1160641: Swift detection of 4U 1630-472 (a.k.a. SWIFT J1633.8-4724A)
  28. Fermi GRB 230227A: Global MASTER-Net observations report
  29. Fermi GRB 230215A: Global MASTER-Net observations report
  30. GRB 221231A: Fermi GBM Observation
  31. GRB 230101A: AstroSat CZTI detection
  32. Fermi GRB 221223A: Global MASTER-Net observations report
  33. GRB 221216A: Swift-XRT refined Analysis
  34. Fermi trigger No 687190301: Global MASTER-Net observations report
  35. GRB 220831A: ATCA 5/9 GHz radio observations
  36. GRB 220711B: Fermi GBM Detection
  37. GRB 220624A: Fermi GBM Detection
  38. Fermi GRB 220623B: Global MASTER-Net observations report
  39. GRB 220623A: Swift-XRT observations
  40. Konus-Wind detection of an intermediate flare from SGR 1935+2154 on June 16
  41. Swift GRB220521.97: Global MASTER-Net observations report
  42. GRB 220514B: MAXI/GSC detection
  43. Fermi-LAT Gamma-ray Observations of IceCube-220509A
  44. MAXI GRB220506.27: Global MASTER-Net observations report
  45. IceCube Alert 220501.95: Global MASTER-Net observations report
  46. GRB 220319A: Mondy optical uper limit
  47. GRB 220315A: MASTER Global Robotic Net optical observations
  48. Konus-Wind detection of GRB 220310A
  49. Fermi trigger No 668410535: Global MASTER-Net observations report
  50. Swift GRB 220306B: Global MASTER-Net observations report
  51. Konus-Wind observation of GRB 220219B
  52. GRB 220210A: BOOTES-5/JGT optical afterglow candidate
  53. GRB 220130A: Fermi GBM Observation
  54. Konus-Wind detection of GRB 220107A
  55. Konus-Wind detection of GRB 210928A
  56. Swift GRB 210919A: Global MASTER-Net observations report
  57. Konus-Wind detection of GRB 210905A
  58. Integral GRB210829.17: Global MASTER-Net observations report
  59. Integral GRB210829.14: Global MASTER-Net observations report
  60. GRB 210807C: Fermi GBM detection
  61. Trigger 1062273: Swift detection of 4U 1700-377
  62. Konus-Wind detection of GRB 210702A
  63. Fermi trigger No 646194855: Global MASTER-Net observations report
  64. Swift GRB210618.07: Global MASTER-Net observations report
  65. Swift-BAT Trigger 1055000/GRB210612.54: MASTER optical source observation
  66. Swift-BAT Trigger 1055000: Swift detection of an outburst from 4U 1543-47
  67. Swift Detection of probable new Swift SGR J1555.2-5402
  68. Fermi GRB 210528A: Global MASTER-Net observations report
  69. GRB 210521A: MAXI/GSC detection
  70. GRB 210514A: update on the BAT trigger time and burst duration
  71. Swift trigger 1047857 is 4U 1700-377
  72. Swift Trigger 1045571 is not a GRB
  73. GRB 210419A: Swift-BAT refined analysis
  74. GRB 210410A: Swift-XRT refined Analysis
  75. Fermi trigger No 639199407: Global MASTER-Net observations report
  76. GRB 210403A: Swift-BAT refined analysis
  77. GRB 210318B: Swift-BAT refined analysis
  78. GRB 210204A: AstroSat CZTI Detection
  79. GECAM detection of a burst possibly from the X-ray burster 4U 0614+09 or GRB 210124A
  80. Fermi GRB 210120A: Global MASTER-Net observations report
  81. Fermi trigger No 631602681: Global MASTER-Net observations report
  82. GRB 210104A: GWAC-F60A optical afterglow observations
  83. Konus-Wind detection of GRB 201216C
  84. IceCube Alert 201014.09: Global MASTER-Net observations report
  85. GRB 201004A: Fermi GBM Final Localization
  86. Fermi trigger No 622618714: Global MASTER-Net observations report
  87. IPN triangulation of GRB 200916B (short)
  88. GRB 200903A: Fermi GBM detection
  89. Swift Trigger 992444 is due to detector noise
  90. Swift Trigger 990358 is due to detector noise
  91. Swift Trigger 989458 is due to detector noise
  92. Fermi GRB 200723A: Global MASTER-Net observations report
  93. GRB 200630A: Swift-BAT refined analysis
  94. GRB 200529A: Swift-BAT refined analysis
  95. GRB 200528A: Swift-BAT refined analysis
  96. Konus-Wind detection of short/hard GRB 200521A
  97. GRB 200519A: Swift-BAT refined analysis
  98. SGR 1935+2154: AstroSat CZTI detection
  99. IceCube-200425A: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  100. GRB 200412B: continued AbAO, Mondy, TSHAO, Terskol optical observations

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