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GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. 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.

Advanced Search Examples (click to copy):

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

24581 results found.

  1. GRB 230227A: Fermi GBM Final Real-time Localization
  2. Fermi trigger No 699029364: Global MASTER-Net observations report
  3. IceCube-230220A: Upper limits from a search for additional neutrino events in IceCube
  4. GRB 230222A: Fermi GBM Final Real-time Localization
  5. Fermi-LAT gamma-ray observations of IceCube-230220A
  6. GRB 230217A: Swift-BAT refined analysis
  7. Fermi GRB 230220B: Global MASTER-Net observations report
  8. GRB 230217A: 6 GHz VLA observations
  9. GRB 230220B: Fermi GBM Final Real-time Localization
  10. GRB 230217A: Gemini-South Optical Observation
  11. IceCube-230217A: Upper limits from a search for additional neutrino events in IceCube
  12. IceCube-230220A - IceCube observation of a high-energy neutrino candidate
  13. GRB 230217A: Fermi GBM observation
  14. IceCube-230217A: BOOTES-4/MET Optical Observations
  15. Fermi-LAT gamma-ray observations of IceCube-230217A
  16. Konus-Wind detection of GRB 230217A
  17. GRB 230217A: Swift-XRT observations
  18. Fermi trigger No 698427992: Global MASTER-Net observations report
  19. IceCube Alert 230217.87: Global MASTER-Net observations report
  20. GRB 230218A: Fermi GBM Final Real-time Localization
  21. GRB 230217A: AGILE/MCAL detection
  22. GRB 230216A: SVOM/C-GFT optical upper limit
  23. GRB 230217A: Swift detection of a short burst
  24. GRB 230217A: Fermi GBM Final Real-time Localization
  25. IceCube-230217A - IceCube observation of a high-energy neutrino candidate track-like event
  26. GRB 230216A: Swift-BAT refined analysis
  27. GRB 230216A: Swift-XRT refined Analysis
  28. Swift GRB 230216A: Global MASTER-Net observations report
  29. GRB 230216A: AKO Upper Limit
  30. GRB 230216A: Swift detection of a burst
  31. Fermi GRB 230215A: Global MASTER-Net observations report
  32. GRB 230215A: Fermi GBM Final Real-time Localization
  33. GRB 230209B: AGILE detection
  34. GRB 230209B: Fermi GBM Observation
  35. IPN triangulation of GRB 230209B
  36. Outburst from LS V +44 17 / RX J0440.9+4431: Transient detection by GRBAlpha
  37. Fermi trigger No 697926015: Global MASTER-Net observations report
  38. Fermi trigger No 697904388: Global MASTER-Net observations report
  39. GRB 230211A: Fermi GBM Final Real-time Localization
  40. GRB 230209B: Swift/BAT-GUANO detection outside the coded FOV
  41. Fermi trigger No 697678542: Global MASTER-Net observations report
  42. Swift Trigger 1153670 is probably not a GRB
  43. GRB 230210A: Fermi GBM Final Real-time Localization
  44. Fermi GRB 230209B: Global MASTER-Net observations report
  45. GRB 230209B: Fermi GBM Final Real-time Localization
  46. GRB 230209A: Fermi GBM Final Real-time Localization
  47. GRB 230207B: Detection by GRBAlpha
  48. GRB 230204B: MASTER early OT detection
  49. GRB 230208A: Fermi GBM Final Real-time Localization
  50. GRB 230207B: Swift/BAT-GUANO detection outside the coded FOV
  51. ZTF23aabmzlp/AT2023azs: Neil Gehrels Swift Observatory X-ray observations
  52. GRB 230207B: AGILE detection of a burst
  53. Fermi GRB 230207A: Global MASTER-Net observations report
  54. GRB 230207A: Fermi GBM Final Real-time Localization
  55. GRB 230204B: LCOGT Optical Upper Limits
  56. Fermi trigger No 697403223: Global MASTER-Net observations report
  57. Fermi trigger No 697396830: Global MASTER-Net observations report
  58. GRB 230204B: Fermi GBM detection
  59. Fermi Gamma-ray Burst Monitor triggers due to recent activity of RX J0440.9+4431 (LS V +44 17)
  60. GRB 230205A: LCOGT Optical Upper Limits
  61. GRB 230204B: 3.6m DOT optical observation
  62. GRB 230205A: SVOM/C-GFT optical upper limit
  63. GRB 230205A: OHP/T193 optical observations
  64. GRB 230204B: VLT/X-shooter redshift
  65. GRB 230205A: Swift-BAT refined analysis (T90 = 2.3 s)
  66. GRB 230204A: Swift-BAT refined analysis
  67. GRB 230205A: Swift-XRT refined Analysis
  68. GRB 230204B: Detection by GRBAlpha
  69. GRB 230204B: AGILE detection
  70. GRB 230205A: Swift detection of a burst
  71. IceCube-230201A: BOOTES-4/MET Optical Upper Limits
  72. GRB 230204B: GIT discovery of the likely optical afterglow
  73. GRB 230204B: Swift/BAT-GUANO detection outside the coded FOV
  74. GRB 230204A/Swift J1552.8-5055: LCOGT Optical Counterpart Candidate
  75. Fermi trigger No 697208885: Global MASTER-Net observations report
  76. Fermi trigger No 697098930: Global MASTER-Net observations report
  77. IceCube-230201A: Upper limits from a search for additional neutrino events in IceCube
  78. ZTF23aabmzlp/AT2023azs: Lulin 1m LOT optical observations
  79. GRB 221216A: Swift-BAT refined analysis
  80. ZTF23aabmzlp/AT2023azs: VLA radio detection
  81. IceCube Alert 230201.26: Global MASTER-Net observations report
  82. Fermi GRB 230201B: Global MASTER-Net observations report
  83. Fermi-LAT gamma-ray observations of IceCube-230201A
  84. GRB 230201B: Fermi GBM Final Real-time Localization
  85. GRB 230126A: Detection by VZLUSAT-2
  86. Fermi GRB 230201A: Global MASTER-Net observations report
  87. IceCube-230201A - IceCube observation of a high-energy neutrino candidate track-like event
  88. GRB 230201A: Fermi GBM Final Real-time Localization
  89. ZTF23aabmzlp/AT2023azs: 1.3m DFOT optical observations
  90. GRB 230130A: Fermi GBM Final Real-time Localization
  91. ZTF23aaarlti/AT2023avj: VLA radio detection
  92. GRB 230129A: Fermi GBM Final Real-time Localization
  93. GRB 230128A: Fermi GBM Final Real-time Localization
  94. ZTF23aabmzlp/AT2023azs: Zwicky Transient Facility discovery of a fast optical transient
  95. IceCube-230122A: BOOTES-2/TELMA Optical Upper Limit
  96. ZTF and LT Observations of AT2023avj, a Candidate Optical Afterglow
  97. GRB 230126A: Fermi GBM Final Real-time Localization
  98. GRB 230124A: Fermi GBM Observation
  99. AMON Coincidence Alert from the sub-threshold IceCube-HAWC search NuEm-230125A
  100. GRB 230124A: Swift/BAT-GUANO detection outside the coded FOV

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