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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').
Advanced Search

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"

4713 results found.

  1. Fermi trigger No 701883729: Global MASTER-Net observations report
  2. GRB 230328B: GRBAlpha detection
  3. GRB 230328B: Nanshan/NEXT 2nd optical observation
  4. GRB 230328B NUTTelA-TAO / BSTI Early Measurements
  5. GRB 230328B: Liverpool Telescope afterglow detection
  6. GRB 230328B: GIT optical follow-up
  7. GRB 230328B: Nanshan/NEXT optical upper limit
  8. GRB 230328B: AstroSat CZTI detection
  9. GRB 230328B: Mondy, AbAO and Kitab optical observations
  10. GRB 230328B: Mondy optical afterglow confirmation
  11. Fermi GRB 230328A: Global MASTER-Net observations report
  12. GRB 230325A: Swift-BAT refined analysis
  13. GRB 230325A: Swift detection of a burst
  14. Fermi trigger No 701313046: Global MASTER-Net observations report
  15. Fermi trigger No 701321709: Global MASTER-Net observations report
  16. Swift GRB 230322B: Global MASTER-Net observations report
  17. GRB 230320B: GRBAlpha detection
  18. Fermi trigger No 701071944: Global MASTER-Net observations report
  19. GRB 230320B: Swift/BAT-GUANO detection outside the coded FOV
  20. Fermi GRB 230320A: Global MASTER-Net observations report
  21. Fermi GRB 230321A: Global MASTER-Net observations report
  22. Fermi trigger No 701058254: Global MASTER-Net observations report
  23. GRB 230321B: AstroSat CZTI detection
  24. GRB 230320B: AstroSat CZTI detection
  25. GRB 230314A: TURBO Optical Upper Limit
  26. Trigger 1160641: Swift detection of 4U 1630-472 (a.k.a. SWIFT J1633.8-4724A)
  27. Fermi trigger No 700976129: Global MASTER-Net observations report
  28. Fermi GRB 230316A: Global MASTER-Net observations report
  29. GRB 230304D: AstroSat CZTI detection
  30. IPN triangulation of GRB 230304B
  31. GRB 230313A: AstroSat CZTI detection
  32. GRB 230307A: Far off-axis NuSTAR detection of the GRB
  33. Fermi GRB 230314A: Global MASTER-Net observations report
  34. GRB 230307A: ATCA radio detection
  35. VZLUSAT-2 detection of SGR 1806-20
  36. GRB 230307A: INTEGRAL upper limit on Hard X-ray afterglow
  37. AMON Coincidence Alert from the sub-threshold IceCube-HAWC search NuEm-230313A
  38. Fermi GRB 230313A: Global MASTER-Net observations report
  39. GRB 230307A: soft X-ray detection with LEIA
  40. GRB 230309A: AstroSat CZTI detection of a bright long GRB
  41. Swift GRB230311.85: Global MASTER-Net observations report
  42. Swift GRB230311.83: Global MASTER-Net observations report
  43. Further improved IPN localization for GRB 230307A
  44. Swift GRB230311.81: Global MASTER-Net observations report
  45. GRB 230307A: SOAR/Goodman detection of the possible host galaxy
  46. Swift GRB230311.84: Global MASTER-Net observations report
  47. Swift GRB230311.82: Global MASTER-Net observations report
  48. TESS Detection of the Optical Afterglow of GRB230307A
  49. GRB 230310A: AstroSat CZTI detection
  50. GRB 230307A: GECKO optical observations and detections of the afterglow
  51. GRB 230307A: MAXI/GSC upper limit
  52. GRB 230307A: Gemini-South Confirmation of the Optical Afterglow
  53. Fermi GRB 230310A: Global MASTER-Net observations report
  54. GRB 230307A: AGILE/MCAL analysis
  55. GRB 230307A: ATLAS information on the ULTRACAM optical afterglow candidate
  56. GRB 230307A: Possible optical afterglow
  57. GRB 230307A: ASO-S/HXI detection
  58. GRB 230228A: NUTTelA-TAO / BSTI Optical Limits
  59. GRB 230308A: AGILE/MCAL detection
  60. GRB 230307A: Upper limits from a neutrino search with IceCube
  61. Fermi GRB 230307A: Global MASTER-Net observations report
  62. GRB 230307A: VZLUSAT-2 detection
  63. Fermi GRB 230308A: Global MASTER-Net observations report
  64. GRB 230307A: Detection by GRBAlpha
  65. GRB 230305A: Detection by GRBAlpha
  66. GRB 230307A: AstroSat CZTI detection
  67. GRB 230307A: possibly the second highest GRB energy fluence ever identified
  68. GRB 230307A: AGILE/MCAL detection
  69. GRB 230307A: Fermi GBM Observation of a very bright burst
  70. Solar Orbiter STIX observation of GRB 230307A
  71. IceCube-230306A: Upper limits from a search for additional neutrino events in IceCube
  72. Fermi-LAT gamma-ray observations of IceCube-230306A
  73. GRB 230307A: GECAM detection of an extremely bright burst
  74. Fermi trigger No 699811746: Global MASTER-Net observations report
  75. IceCube-230306A - IceCube observation of a high-energy neutrino candidate
  76. IceCube Alert 230306.46: Global MASTER-Net observations report
  77. GRB 230304C: AstroSat CZTI detection
  78. GRB 230304B: AstroSat CZTI detection
  79. GRB 230304A: AstroSat CZTI detection
  80. GRB 230304B: Detection by GRBAlpha
  81. Fermi GRB 230301B: Global MASTER-Net observations report
  82. Fermi trigger No 699294715: Global MASTER-Net observations report
  83. GRB 230228A: OSN optical upper limit
  84. GRB 230227A: Fermi GBM Final Real-time Localization
  85. Fermi trigger No 699029364: Global MASTER-Net observations report
  86. GRB 230216A Mondy Observations
  87. IceCube-230220A: Upper limits from a search for additional neutrino events in IceCube
  88. GRB 230216B: CALET Gamma-Ray Burst Monitor detection
  89. GRB 230216B: AstroSat CZTI detection
  90. Fermi trigger No 697904388: Global MASTER-Net observations report
  91. Fermi trigger No 697403223: Global MASTER-Net observations report
  92. Fermi trigger No 697396830: Global MASTER-Net observations report
  93. Fermi Gamma-ray Burst Monitor triggers due to recent activity of RX J0440.9+4431 (LS V +44 17)
  94. GRB 230205A: SVOM/C-GFT optical upper limit
  95. GRB 230205A: OHP/T193 optical observations
  96. GRB 230204B: Detection by GRBAlpha
  97. IceCube-230201A: BOOTES-4/MET Optical Upper Limits
  98. Fermi trigger No 697208885: Global MASTER-Net observations report
  99. GRB 230201B: TURBO Optical Upper Limits
  100. Fermi Gamma-ray Burst Monitor trigger 230203275 / 697098930 is not a GRB

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