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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"

39401 results found.

  1. Fermi GRB 230207A: Global MASTER-Net observations report
  2. GRB 230207A: Fermi GBM Final Real-time Localization
  3. GRB 230204B: LCOGT Optical Upper Limits
  4. GRB 230204B: Swift/UVOT Upper Limits
  5. Fermi trigger No 697403223: Global MASTER-Net observations report
  6. Fermi trigger No 697396830: Global MASTER-Net observations report
  7. GRB 230205A: Swift/UVOT Upper Limits
  8. GRB 230204B: Fermi GBM detection
  9. GRB 230205A: LCOGT Optical Upper Limits
  10. GRB 230204B: Swift-XRT afterglow detection
  11. GRB 230204B: 3.6m DOT optical observation
  12. GRB 230205A: SVOM/C-GFT optical upper limit
  13. GRB 230205A: OHP/T193 optical observations
  14. GRB 230204B: VLT/X-shooter redshift
  15. GRB 230205A: Swift-BAT refined analysis (T90 = 2.3 s)
  16. GRB 230204A: Swift-BAT refined analysis
  17. GRB 230204B: ATLAS detection of the optical afterglow and a projected location in a nearby galaxy group
  18. GRB 230205A: Swift-XRT refined Analysis
  19. GRB 230204B: Swift ToO observations
  20. GRB 230205A: Enhanced Swift-XRT position
  21. GRB 230205A: BOOTES-5/JGT early optical upper limit
  22. GRB 230204B: Detection by GRBAlpha
  23. GRB 230204B: AGILE detection
  24. GRB 230205A: Swift detection of a burst
  25. IceCube-230201A: BOOTES-4/MET Optical Upper Limits
  26. GRB 230204B: GIT discovery of the likely optical afterglow
  27. GRB 230204B: AstroSat CZTI detection
  28. GRB 230204B: Swift/BAT-GUANO detection outside the coded FOV
  29. GRB 230204A: Swift/UVOT Upper Limits
  30. GRB 230204B: MAXI/GSC detection
  31. GRB 230204A: Swift-XRT refined Analysis
  32. GRB 230204A/Swift J1552.8-5055: LCOGT Optical Counterpart Candidate
  33. Fermi trigger No 697208885: Global MASTER-Net observations report
  34. GRB 230204A: Enhanced Swift-XRT position
  35. GRB 230204A: Swift detection of a possible burst (or possible transient Swift J1552.8-5055)
  36. GRB 230201B: TURBO Optical Upper Limits
  37. Fermi Gamma-ray Burst Monitor trigger 230203275 / 697098930 is not a GRB
  38. Fermi trigger No 697098930: Global MASTER-Net observations report
  39. GRB 221216A: Swift-BAT refined analysis
  40. IceCube Alert 230201.26: Global MASTER-Net observations report
  41. Fermi GRB 230201B: Global MASTER-Net observations report
  42. Fermi-LAT gamma-ray observations of IceCube-230201A
  43. GRB 230201B: Fermi GBM Final Real-time Localization
  44. GRB 230126A: Detection by VZLUSAT-2
  45. Fermi GRB 230201A: Global MASTER-Net observations report
  46. IceCube-230201A - IceCube observation of a high-energy neutrino candidate track-like event
  47. GRB 221009A: radio afterglow detection with the EVN
  48. GRB 230201A: Fermi GBM Final Real-time Localization
  49. ZTF23aaarlti/AT2023avj: Assy continued optical observations
  50. ZTF23aabmzlp/AT2023azs: Mondy and AbAO optical observations
  51. AT2023avj: X-ray Detection with Swift/XRT
  52. ZTF23aabmzlp/AT2023azs: 1.3m DFOT optical observations
  53. GRB 230129A: AstroSat CZTI detection
  54. GRB 230128A: AstroSat CZTI detection
  55. GRB 230130A: Fermi GBM Final Real-time Localization
  56. GRB 230129A: Fermi GBM Final Real-time Localization
  57. GRB 230128A: Fermi GBM Final Real-time Localization
  58. ZTF23aabmzlp/AT2023azs: GIT confirmation of the likely afterglow
  59. ZTF23aabmzlp/AT2023azs: Zwicky Transient Facility discovery of a fast optical transient
  60. AT2023avj ZTF Candidate: Assy optical observations
  61. GRB 230126A: Fermi GBM Final Real-time Localization
  62. Trigger 1150965: Swift detection of LS V +44 17
  63. GRB 230124A: Fermi GBM Observation
  64. GRB 230124A: Swift/BAT-GUANO detection outside the coded FOV
  65. GRB 230114B: Detection by VZLUSAT-2
  66. GRB 230123A: LCOGT Optical Upper Limits
  67. Fermi GRB 230124A: Global MASTER-Net observations report
  68. GRB 230124A: Fermi GBM Final Real-time Localization
  69. GRB 230123A: Swift-BAT refined analysis
  70. GRB 230122A: Swift/BAT-GUANO detection
  71. Fermi-LAT gamma-ray observations of IceCube-230122A
  72. GRB 230123A: Swift/UVOT Upper Limits
  73. GRB 230123A: Swift-XRT refined Analysis
  74. GRB 230123A: Enhanced Swift-XRT position
  75. GRB 230123A: Zadko observatory - Gingin optical observations
  76. GRB 230116C: Swift-XRT observations
  77. GRB 230123A: Swift detection of a burst
  78. IceCube Alert 230122.16: Global MASTER-Net observations report
  79. GRB 230116B: Fermi GBM observation
  80. Trigger 1150107: Swift detection of LS V +44 17
  81. GRB 230120A: AstroSat CZTI detection
  82. IPN triangulation of GRB 230116B (short)
  83. GRB 230119A: CALET Gamma-Ray Burst Monitor detection
  84. GRB 230116D: 3.6m DOT optical upper limit
  85. GRB 230119A: Fermi GBM Final Real-time Localization
  86. Fermi GRB 230118A: Global MASTER-Net observations report
  87. GRB 230118A: Fermi GBM Final Real-time Localization
  88. GRB 230116D: Swift-BAT refined analysis
  89. GRB 230116C: Swift-BAT refined analysis
  90. GRB 230116D: SAO RAS further observations
  91. GRB 230116D: SAO RAS photometry
  92. GRB 230116D: KGO RC-25 optical observations
  93. GRB 230116D: Sintez-Newton/CrAO optical observations
  94. GRB 230116D: LCOGT Optical Upper Limit
  95. GRB 230116D: SAO RAS redshift
  96. Fermi trigger No 695569700: Global MASTER-Net observations report
  97. GRB 230116D: Swift-XRT refined Analysis
  98. Fermi GRB 230117A: Global MASTER-Net observations report
  99. GRB 230117A: Fermi GBM Final Real-time Localization
  100. GRB 230116D: GIT optical follow-up

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