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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"

28227 results found.

  1. GRB 240114A: MAXI/GSC detection
  2. GRB 240112C: Swift/UVOT Detection
  3. GRB 240112C: Fermi GBM Detection
  4. GRB 240112C: Swift-XRT refined Analysis
  5. GRB 240112E: Fermi GBM Final Localization
  6. GRB 240112D: Fermi GBM Final Real-time Localization
  7. GRB 240112C: Swift detection of a burst with an optical counterpart
  8. GRB 240112B: Fermi GBM Final Real-time Localization
  9. GRB 240112A: GECAM detection of a burst
  10. GRB 240110A: AstroSat CZTI detection
  11. Fermi-LAT detection of increased gamma-ray activity of blazar PKS 0446+11, located inside the IceCube-240105A error region
  12. GRB 240108A: Glowbug gamma-ray detection
  13. GRB 231214A: ATCA Radio Upper Limits
  14. GRB 240106B: Glowbug gamma-ray detection
  15. GRB 240106A: Glowbug gamma-ray detection
  16. GRB 240109B: Fermi GBM Final Real-time Localization
  17. Konus-Wind detection of GRB 240101C
  18. GRB 231215A: radio detection with the VLA
  19. GRB 230812B: further radio observations with the VLA
  20. GRB 240107A: AstroSat CZTI detection
  21. GRB 240109A: Swift detection of a short burst
  22. IceCube-240105A: JCMT SCUBA2 Detection of Two Bright Submillimeter Sources
  23. GRB 240106A: GRBAlpha detection
  24. GRB 240107A: MAXI/GSC detection
  25. GRB 240106B: Fermi GBM Final Real-time Localization
  26. GRB 240106A: Fermi GBM Final Real-time Localization
  27. IPN triangulation of GRB 240101C (short)
  28. GRB 240101A: 1.3m DFOT optical observations
  29. IceCube-240105A - IceCube observation of a high-energy neutrino candidate track-like event
  30. GRB 240102A: 1.3m DFOT optical upper limit
  31. GRB 240101B: 1.3m DFOT optical upper limit
  32. GRB 240101C: Swift/BAT-GUANO detection of a short burst
  33. GRB 240102C: AstroSat CZTI detection
  34. GRB 240101C: AstroSat CZTI detection
  35. GRB 240102A: Swift/UVOT Upper Limits
  36. GRB 240102A: Enhanced Swift-XRT position
  37. GRB 240101B: Swift-XRT refined Analysis
  38. GRB 240102A: Swift-XRT refined Analysis
  39. GRB 240102A: LCOGT Optical Upper Limits
  40. GRB240102A: BOOTES-6/DPRT optical upper limit
  41. GRB 240102B: Fermi GBM Final Real-time Localization
  42. GRB 240101B: MarSEC Observatory, Vicenza, Italy, UPPER LIMIT
  43. GRB 240102A: Swift detection of a burst
  44. GRB 240101A: Terskol Zeiss-2000 optical observations
  45. GRB 240101C: GRBAlpha detection
  46. GRB 240101B: Swift/UVOT Upper Limits
  47. GRB 240101A: Swift/UVOT Upper Limits
  48. GRB 240101A: Swift-XRT refined Analysis
  49. GRB 240101B: Enhanced Swift-XRT position
  50. GRB 240101B: KAIT Optical Upper Limit
  51. GRB 240101A: KAIT Optical Upper Limit
  52. GRB 240101A: Enhanced Swift-XRT position
  53. GRB 240101C: Fermi GBM Final Localization
  54. GRB 240101B: Swift detection of a burst
  55. GRB 240101A: Swift detection of a burst
  56. GRB 231230A: Swift-XRT refined Analysis
  57. GRB 231230A: GOTO optical upper limits
  58. GRB 231230A: Enhanced Swift-XRT position
  59. GRB 231230A: Swift/UVOT Upper Limits
  60. GRB 231230A: NOT optical upper limits
  61. GRB 231230A: Prompt enhanced Swift-XRT position
  62. GRB 231230A: Swift detection of a burst
  63. GRB 231230A: Fermi GBM Final Real-time Localization
  64. GRB 231210B: BOOTES-7 optical upper limit
  65. IPN triangulation of GRB 231224A (short)
  66. GRB 231224A: Fermi GBM Final Real-time Localization
  67. GRB 231222B: GRBAlpha detection
  68. GRB 231222B: Swift-XRT afterglow detection
  69. GRB 231222B: Fermi GBM Detection
  70. GRB 231222B: Fermi-LAT detection
  71. GRB 231222A: Tiled Swift observations
  72. IceCube-231211A: GRANDMA observations of PKS2047+098
  73. GRID detection of GRB 231215A
  74. GRB 231222A: Fermi GBM Final Real-time Localization
  75. GRB 231220A: Swift-XRT follow-up observations
  76. GRB 231220A: Swift ToO observations
  77. GRB 231220A: Swift/BAT-GUANO arcminute localization of a long burst
  78. GRB 231220A: Fermi GBM Final Real-time Localization
  79. GRB 231210B: new optical transient detected with the Greenhill Observatory University of Tasmania within the BAT-Swift enhanced position
  80. GRB 231219A: Fermi GBM Final Real-time Localization
  81. GRID detection of GRB 231205B
  82. GRID detection of GRB 231205A
  83. GRB 231216A: GAD Observatory, La Spezia, Italy upper limit
  84. GRB 231216A: optical upper limits from the INAF Asiago Observatory
  85. GRB 231216A: 10.4 m GTC optical upper limit
  86. GRB 231215A: AMI-LA radio detection
  87. GRB 231216A: Nanshan/HMT optical upper limit
  88. GRB 231216A: LCOGT Optical Upper Limits
  89. GRB 231216A: Swift-XRT refined analysis correction
  90. GRB 231216A: Swift-XRT refined Analysis
  91. GRB 231216A: AST3-3 YaoAn Optical Upper Limit
  92. GRB 231216A: REM NIR upper limits
  93. GRB 231216A: Swift/UVOT Upper Limits
  94. GRB 231216A: R-band observations from T120 at Observatoire de Haute-Provence
  95. GRB 231216A: GIT optical upper limit
  96. GRB 231216A: NOT optical upper limits
  97. GRB 231216A: BOOTES-2/TELMA optical upper limit
  98. GRB 231215A: GRBAlpha detection
  99. GRB 231216A: Swift detection of a burst
  100. Konus-Wind detection of GRB 231215A

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