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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').

17435 results found.

  1. GRB 240112C: Swift/UVOT Detection
  2. GRB 240112C: Fermi GBM Detection
  3. GRB 240112C: Swift-XRT refined Analysis
  4. GRB 240112C: SAO RAS optical observations
  5. Swift GRB 240112C: Global MASTER-Net observations report
  6. GRB 240109A: Swift-BAT refined analysis
  7. GRB 240112C: Swift detection of a burst with an optical counterpart
  8. GRB 240112A: GECAM detection of a burst
  9. GRB 240109A: Fermi GBM Observation
  10. GRB 231214A: ATCA Radio Upper Limits
  11. Konus-Wind detection of GRB 240101C
  12. Swift GRB240109.17: Global MASTER-Net observations report
  13. GRB 240109A: Swift detection of a short burst
  14. LIGO/Virgo/KAGRA S240104bl: Upper limits from Swift/BAT-GUANO
  15. IPN triangulation of GRB 240101C (short)
  16. GRB GRB240101C: Fermi GBM observation
  17. GRB 240101A: 1.3m DFOT optical observations
  18. GRB 240102A: 1.3m DFOT optical upper limit
  19. GRB 240101B: 1.3m DFOT optical upper limit
  20. GRB 240101C: Swift/BAT-GUANO detection of a short burst
  21. GRB 231220A: Swift-UVOT upper limit
  22. GRB 240102A: Swift-BAT refined analysis
  23. GRB 240102A: Swift/UVOT Upper Limits
  24. GRB 231230A: Swift-BAT refined analysis
  25. GRB 240101A: Swift-BAT refined analysis
  26. GRB 240101B: Swift-BAT refined analysis
  27. GRB 240102A: Enhanced Swift-XRT position
  28. GRB 240101B: Swift-XRT refined Analysis
  29. GRB 240102A: Swift-XRT refined Analysis
  30. GRB 240102A: LCOGT Optical Upper Limits
  31. GRB240102A: BOOTES-6/DPRT optical upper limit
  32. GRB 240101B: MarSEC Observatory, Vicenza, Italy, UPPER LIMIT
  33. GRB 240102A: Swift detection of a burst
  34. GRB 240101A: Terskol Zeiss-2000 optical observations
  35. GRB 240101B: Swift/UVOT Upper Limits
  36. GRB 240101A: Swift/UVOT Upper Limits
  37. GRB 240101A: Swift-XRT refined Analysis
  38. GRB 240101B: Enhanced Swift-XRT position
  39. GRB 240101B: KAIT Optical Upper Limit
  40. GRB 240101A: KAIT Optical Upper Limit
  41. GRB 240101A: Enhanced Swift-XRT position
  42. Swift GRB240101.85: Global MASTER-Net observations report
  43. GRB 240101B: Swift detection of a burst
  44. GRB 240101A: Swift detection of a burst
  45. GRB231230A: Fermi GBM Observation
  46. GRB 231230A: Swift-XRT refined Analysis
  47. GRB 231230A: GOTO optical upper limits
  48. GRB 231230A: Enhanced Swift-XRT position
  49. GRB 231230A: Swift/UVOT Upper Limits
  50. GRB 231230A: Prompt enhanced Swift-XRT position
  51. GRB 231230A: Swift detection of a burst
  52. Swift GRB231230.06: Global MASTER-Net observations report
  53. GRB 231210B: BOOTES-7 optical upper limit
  54. Swift Triggers 1205103, 1205104, 1205107 and 1205110 are not astrophysical events
  55. LIGO/Virgo/KAGRA S231224e: Upper limits from Swift/BAT-GUANO
  56. GRB 231222B: Swift-XRT afterglow detection
  57. GRB 231222B: Fermi-LAT detection
  58. GRB 231222A: Tiled Swift observations
  59. GRID detection of GRB 231215A
  60. GRB 231220A: Swift-XRT follow-up observations
  61. GRB 231220A: Swift ToO observations
  62. GRB 231220A: Swift/BAT-GUANO arcminute localization of a long burst
  63. GRB 231210B: new optical transient detected with the Greenhill Observatory University of Tasmania within the BAT-Swift enhanced position
  64. GRID detection of GRB 231205B
  65. GRB 231216A: GAD Observatory, La Spezia, Italy upper limit
  66. GRB 231214B: Fermi GBM observation
  67. GRB 231216A: 10.4 m GTC optical upper limit
  68. GRB 231216A: Nanshan/HMT optical upper limit
  69. GRB 231216A: LCOGT Optical Upper Limits
  70. GRB 231216A: Osservatorio Astronomico Nastro Verde upper limit
  71. GRB 231216A: Swift-XRT refined analysis correction
  72. GRB 231215A: Osservatorio Astronomico Nastro Verde upper limit
  73. GRB 231216A: Swift-XRT refined Analysis
  74. GRB 231216A: AST3-3 YaoAn Optical Upper Limit
  75. GRB 231216A: REM NIR upper limits
  76. GRB 231216A: Swift/UVOT Upper Limits
  77. GRB 231216A: Swift-BAT refined analysis
  78. GRB 231215A: Swift-BAT refined analysis
  79. GRB 231214A: Swift-BAT refined analysis
  80. GRB 231216A: R-band observations from T120 at Observatoire de Haute-Provence
  81. GRB 231216A: GIT optical upper limit
  82. GRB 231216A: BOOTES-2/TELMA optical upper limit
  83. GRB 231215A: GRBAlpha detection
  84. Swift GRB231216.77: Global MASTER-Net observations report
  85. GRB 231216A: Swift detection of a burst
  86. Konus-Wind detection of GRB 231215A
  87. GRB 231215A: NOT optical observations
  88. GRB 231214A: Swift/UVOT Upper Limits
  89. GRB 231205B: VZLUSAT-2 detection
  90. GRB 231215A: Fermi GBM observation
  91. GRB 231215A: CALET Gamma-Ray Burst Monitor detection
  92. GRB 231215A: Swift/UVOT Detection
  93. GRB 231215A: Swift-XRT refined Analysis
  94. GRB 231215A: BOOTES-4/MET optical detection
  95. GRB 231215A: AKO Optical Upper Limit
  96. GRB 231215A: AGILE detection
  97. GRB 231214A: Fermi GBM observation
  98. Konus-Wind detection of GRB 231210B
  99. GRB 231215A: Enhanced Swift-XRT position
  100. GRB 231214A: REM optical/NIR upper limits

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