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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').

17099 results found.

  1. GRB 240102A: 1.3m DFOT optical upper limit
  2. GRB 240101B: 1.3m DFOT optical upper limit
  3. GRB 240101C: Swift/BAT-GUANO detection of a short burst
  4. GRB 231220A: Swift-UVOT upper limit
  5. GRB 240102A: Swift-BAT refined analysis
  6. GRB 240102A: Swift/UVOT Upper Limits
  7. GRB 231230A: Swift-BAT refined analysis
  8. GRB 240101A: Swift-BAT refined analysis
  9. GRB 240101B: Swift-BAT refined analysis
  10. GRB 240102A: Enhanced Swift-XRT position
  11. GRB 240101B: Swift-XRT refined Analysis
  12. GRB 240102A: Swift-XRT refined Analysis
  13. GRB 240102A: LCOGT Optical Upper Limits
  14. GRB240102A: BOOTES-6/DPRT optical upper limit
  15. GRB 240101B: MarSEC Observatory, Vicenza, Italy, UPPER LIMIT
  16. GRB 240102A: Swift detection of a burst
  17. GRB 240101A: Terskol Zeiss-2000 optical observations
  18. GRB 240101B: Swift/UVOT Upper Limits
  19. GRB 240101A: Swift/UVOT Upper Limits
  20. GRB 240101A: Swift-XRT refined Analysis
  21. GRB 240101B: Enhanced Swift-XRT position
  22. GRB 240101B: KAIT Optical Upper Limit
  23. GRB 240101A: KAIT Optical Upper Limit
  24. GRB 240101A: Enhanced Swift-XRT position
  25. Swift GRB240101.85: Global MASTER-Net observations report
  26. GRB 240101B: Swift detection of a burst
  27. GRB 240101A: Swift detection of a burst
  28. GRB231230A: Fermi GBM Observation
  29. GRB 231230A: Swift-XRT refined Analysis
  30. GRB 231230A: GOTO optical upper limits
  31. GRB 231230A: Enhanced Swift-XRT position
  32. GRB 231230A: Swift/UVOT Upper Limits
  33. GRB 231230A: Prompt enhanced Swift-XRT position
  34. GRB 231230A: Swift detection of a burst
  35. Swift GRB231230.06: Global MASTER-Net observations report
  36. GRB 231210B: BOOTES-7 optical upper limit
  37. Swift Triggers 1205103, 1205104, 1205107 and 1205110 are not astrophysical events
  38. LIGO/Virgo/KAGRA S231224e: Upper limits from Swift/BAT-GUANO
  39. GRB 231222B: Swift-XRT afterglow detection
  40. GRB 231222B: Fermi-LAT detection
  41. GRB 231222A: Tiled Swift observations
  42. GRID detection of GRB 231215A
  43. GRB 231220A: Swift-XRT follow-up observations
  44. GRB 231220A: Swift ToO observations
  45. GRB 231220A: Swift/BAT-GUANO arcminute localization of a long burst
  46. GRB 231210B: new optical transient detected with the Greenhill Observatory University of Tasmania within the BAT-Swift enhanced position
  47. GRID detection of GRB 231205B
  48. GRB 231216A: GAD Observatory, La Spezia, Italy upper limit
  49. GRB 231214B: Fermi GBM observation
  50. GRB 231216A: 10.4 m GTC optical upper limit
  51. GRB 231216A: Nanshan/HMT optical upper limit
  52. GRB 231216A: LCOGT Optical Upper Limits
  53. GRB 231216A: Osservatorio Astronomico Nastro Verde upper limit
  54. GRB 231216A: Swift-XRT refined analysis correction
  55. GRB 231215A: Osservatorio Astronomico Nastro Verde upper limit
  56. GRB 231216A: Swift-XRT refined Analysis
  57. GRB 231216A: AST3-3 YaoAn Optical Upper Limit
  58. GRB 231216A: REM NIR upper limits
  59. GRB 231216A: Swift/UVOT Upper Limits
  60. GRB 231216A: Swift-BAT refined analysis
  61. GRB 231215A: Swift-BAT refined analysis
  62. GRB 231214A: Swift-BAT refined analysis
  63. GRB 231216A: R-band observations from T120 at Observatoire de Haute-Provence
  64. GRB 231216A: GIT optical upper limit
  65. GRB 231216A: BOOTES-2/TELMA optical upper limit
  66. GRB 231215A: GRBAlpha detection
  67. Swift GRB231216.77: Global MASTER-Net observations report
  68. GRB 231216A: Swift detection of a burst
  69. Konus-Wind detection of GRB 231215A
  70. GRB 231215A: NOT optical observations
  71. GRB 231214A: Swift/UVOT Upper Limits
  72. GRB 231205B: VZLUSAT-2 detection
  73. GRB 231215A: Fermi GBM observation
  74. GRB 231215A: CALET Gamma-Ray Burst Monitor detection
  75. GRB 231215A: Swift/UVOT Detection
  76. GRB 231215A: Swift-XRT refined Analysis
  77. GRB 231215A: BOOTES-4/MET optical detection
  78. GRB 231215A: AKO Optical Upper Limit
  79. GRB 231215A: AGILE detection
  80. GRB 231214A: Fermi GBM observation
  81. Konus-Wind detection of GRB 231210B
  82. GRB 231215A: Enhanced Swift-XRT position
  83. GRB 231214A: REM optical/NIR upper limits
  84. GRB 231215A: GROWTH-India optical follow-up
  85. GRB 231215A : Nanshan/HMT optical observations
  86. GRB 231215A: AstroSat CZTI detection
  87. GRB 231215A : MITSuME Akeno optical afterglow candidate detection
  88. GRB 231214A: Swift-XRT refined Analysis
  89. GRB 231215A: Mondy optical bright afterglow detection
  90. GRB 231214A: AstroSat CZTI detection
  91. GRB 231215C: MASTER OT detection
  92. Swift GRB231215.41: Global MASTER-Net observations report
  93. GRB 231215A: Swift-XRT observations
  94. GRB 231215A: Swift detection of a burst
  95. GRB 231214A: Fermi-LAT detection
  96. GRB 231214A: Enhanced Swift-XRT position
  97. GRB 231214B: Swift/BAT-GUANO detection of a burst
  98. GRB231214A: BOOTES-6/DPRT optical upper limit
  99. Swift GRB231214.85: Global MASTER-Net observations report
  100. GRB 231214A: Swift detection of a burst

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