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تسجيل مستخدم جديدJet-environment interactions in FRI radio galaxies
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R. A. Laing
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There is now unequivocal evidence that the jets in FR I radio galaxies are initially relativistic, decelerating flows. On the assumption that they are axisymmetric and intrinsically symmetrical (a good approximation close to the nucleus), we can make models of their geometry, velocity, emissivity and field structure whose parameters can be determined by fitting to deep VLA observations. Mass entrainment - either from stellar mass loss within the jet volume or via a boundary layer at the jet surface - is the most likely cause for deceleration. This idea is quantitatively consistent with the velocity field and geometry inferred from kinematic modelling and the external gas density and pressure profiles derived from X-ray observations. The jets must initially be very light, perhaps with an electron-positron composition.
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(ABRIDGED) We present here the results from new Very Long Baseline Array observations at 1.6 and 5 GHz of 19 galaxies of a complete sample of 21 UGC FRI radio galaxies. New Chandra data of two sources, viz., UGC00408 and UGC08433, are combined with t
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