Monitoring the Microarcsecond Quasar J1819+3845

  • J. Dennett-Thorpe
  • A. G. De Bruyn


We present the results of a year-long monitoring campaign on J1819+3845. We interpretthe results of this WSRT campaign to infer critical source parameters such as source lifetimeand structure on tens of microarcseconds. The long lifetime of the source at such high brightnesstemperatures requires continuous energy injection or exotic emission processes. We have previouslyinterpreted the extreme scintillation of J1819+ 3845 as due to a relatively nearby (~ 20 pc) scatteringscreen. We show this screen has a velocity w.r.t. the LSR of ~ 25 km s-1, as measured by thechanging scintillation properties throughout the year: the ‘velocity parallax’.


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Copyright information

© Springer Science+Business Media Dordrecht 2001

Authors and Affiliations

  • J. Dennett-Thorpe
    • 1
  • A. G. De Bruyn
    • 2
  1. 1.Kapteyn InstituteGroningenThe Netherlands
  2. 2.ASTRONDwingelooThe Netherlands

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