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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"

3136 results found.

  1. IceCube Alert 240307.32: Global MASTER-Net observations report
  2. GRB 240306A: AstroSat CZTI detection
  3. GRB 240305C: AstroSat CZTI detection of a short burst
  4. Improved IPN triangulation of GRB 240227A (short)
  5. Swift Trigger 1218701: Yes, we triggered on Swift J151857.0-572147 again
  6. Fermi GRB 240229A: Global MASTER-Net observations report
  7. GRB 240225C: AstroSat CZTI detection
  8. GRB 240225B: AstroSat CZTI detection
  9. Transient EPW20240219aa: 7DT Optical Upper Limits
  10. Transient EPW20240219aa: upper limit in gamma-ray range from SPI-ACS/INTEGRAL observations
  11. Insight-HXMT/HE Sub-Threshold Detection of Transient EPW20240219aa
  12. Transient EPW20240219aa: Liverpool Telescope non-detection and limiting magnitude
  13. Fermi GBM Sub-Threshold Detection of EPW20240219aa as a likely GRB
  14. EPW20240219aa is Likely a GRB Event
  15. Fermi trigger No 729914426: Global MASTER-Net observations report
  16. GRB 240209A: Wendelstein Optical Observations
  17. Fermi trigger No 729152364: Global MASTER-Net observations report
  18. GRB 240205B: AstroSat CZTI detection
  19. Fermi trigger No 729012023: Global MASTER-Net observations report
  20. GRB 240204A: AstroSat CZTI detection
  21. GRB 240205B: Skynet Optical Afterglow Observations
  22. Fermi trigger No 728749569: Global MASTER-Net observations report
  23. IceCube Alert 240204.38: Global MASTER-Net observations report
  24. GRB 240201A: AstroSat CZTI detection
  25. GRB 240125A: AstroSat CZTI detection of a short burst
  26. GRB 240124B: AstroSat CZTI detection
  27. GRB 240123C: AstroSat CZTI detection
  28. IPN triangulation of GRB 240123C (short)
  29. GRB 240123A: SAO RAS optical observations
  30. Fermi GRB 240123B: Global MASTER-Net observations report
  31. GRB 240122A: GOTO optical counterpart candidate
  32. GRB 240119A: AstroSat CZTI detection of a short burst
  33. GRB 240118D: AstroSat CZTI detection
  34. GRB 240117A: AstroSat CZTI detection
  35. IPN triangulation of GRB 240112A (long)
  36. GRB 240115B: AstroSat CZTI detection
  37. Fermi trigger No 726773850: Global MASTER-Net observations report
  38. Fermi GRB 240112D: Global MASTER-Net observations report
  39. Fermi trigger No 726774492: Global MASTER-Net observations report
  40. GRB 240110A: AstroSat CZTI detection
  41. GRB 240107A: AstroSat CZTI detection
  42. GRB 240107A: MAXI/GSC detection
  43. Fermi trigger No 726194053: Global MASTER-Net observations report
  44. GRB 240106A: Fermi GBM Final Real-time Localization
  45. IPN triangulation of GRB 240101C (short)
  46. GRB 240102C: AstroSat CZTI detection
  47. GRB 240101C: AstroSat CZTI detection
  48. GRB 240101B: MarSEC Observatory, Vicenza, Italy, UPPER LIMIT
  49. Swift GRB231230.06: Global MASTER-Net observations report
  50. LAT GRB231222.31: Global MASTER-Net observations report
  51. IceCube-231211A: GRANDMA observations of PKS2047+098
  52. GRB 231216A: Nanshan/HMT optical upper limit
  53. GRB 231215A: GRBAlpha detection
  54. Swift GRB231216.77: Global MASTER-Net observations report
  55. GRB 231216A: Swift detection of a burst
  56. GRB 231215A: AstroSat CZTI detection
  57. GRB 231214A: AstroSat CZTI detection
  58. GRB231214A: BOOTES-6/DPRT optical upper limit
  59. IceCube Alert 231211.03: Global MASTER-Net observations report
  60. GRB 231210B: detection of the optical counterpart with the LCOGT 40cm telescope at Sutherland Observatory
  61. GRB 231208A: AstroSat CZTI detection of a faint burst
  62. Fermi trigger No 723581802: Global MASTER-Net observations report
  63. GRB 231204A: AstroSat CZTI detection
  64. GRB 231204A: Fermi GBM Final Real-time Localization
  65. Fermi trigger No 723279695: Global MASTER-Net observations report
  66. GRB 231129C: AstroSat CZTI detection
  67. GRB 231127A: AstroSat CZTI detection
  68. GRB 231125A: AstroSat CZTI detection of a short burst
  69. GRB 231123A: AstroSat CZTI detection
  70. Fermi trigger No 722400249: Global MASTER-Net observations report
  71. GRB 231122B: AstroSat CZTI detection
  72. Fermi trigger No 722349867: Global MASTER-Net observations report
  73. Fermi trigger No 722039659: Global MASTER-Net observations report
  74. GRB 231118A: AstroSat CZTI detection
  75. GRB 231117A: AstroSat CZTI detection of a bright short burst
  76. Fermi GRB 231114A: Global MASTER-Net observations report
  77. GRB 231110A: AstroSat CZTI detection
  78. GRB 231109A: Fermi GBM Final Localization
  79. Fermi trigger No 721204446: Global MASTER-Net observations report
  80. Fermi GRB 231108A: Global MASTER-Net observations report
  81. GRB 231106A: AstroSat CZTI detection
  82. Fermi GRB 231103A: Global MASTER-Net observations report
  83. GRB 231104A: AstroSat CZTI detection
  84. GRB 231030B: AstroSat CZTI detection
  85. GRB 231028A: AstroSat CZTI detection
  86. Fermi trigger No 720224759: Global MASTER-Net observations report
  87. GRB 231028A: Swift detection of a burst
  88. IceCube Alert 231027.18: Global MASTER-Net observations report
  89. LIGO/Virgo/KAGRA S231025t: Global MASTER-Net observations report
  90. LIGO/Virgo/KAGRA S231025a: Global MASTER-Net observations report
  91. GRB 231024A: LCOGT and ZTF detections of the GOTO optical counterpart candidate
  92. GRB 231020A: AstroSat CZTI detection
  93. GRB 231020B: AstroSat CZTI detection
  94. Fermi GRB 231020A: Global MASTER-Net observations report
  95. GRB 231019A: Fermi GBM Final Real-time Localization
  96. GRB 231015A: AstroSat CZTI detection
  97. GRB 231018A: Fermi GBM Final Real-time Localization
  98. GRB 231012A: Fermi GBM Final Real-time Localization
  99. AT2023sva / GRB230916B: GIT observations of the afterglow
  100. LIGO/Virgo/KAGRA S230922g: DECam GW-MMADS candidates

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