Constraints on bent beams in narrow angle tail radio sources

Abstract

The physics of bent radio luminous plasma beams is discussed and constraintson the momentum and energy flux are examined. Expressions for the bulk velocity,particle density, Mach number, and efficiency of conversion of bulk kinetic andinternal energy into radio luminosity are given. VLA data on the intensityratios of opposing jets in a sample of narrow angle tail (NAT) sources are usedto set an upper limit of 0.2c to the bulk velocity of the beams/plasmons. Within the context of models for NATs, order-of-magnitude constraints are placed on the bulk velocities, particle densities, efficiencies, and mass loss rates of the beams/ plasmons in 19 NATs.