MILDLY RELATIVISTIC, BALLISTIC CORKSCREW JETS AS ROTATED SPIRALS

Relativistic, corkscrew jets are produced by some Galactic compact objects (notably, the SS433 outflow) and by some of the central monsters of quasars or AGN. As the result of arrival time-delay effects, the projections of the outflow locus onto the observed plane of the sky are remarkably different for the (blueshifted) jet and the (redshifted) counterjet. In terms of a ballistic, precessing jet model, we show that for a range of outflow parameters these relativistic effects correspond to apparent changes in: the orientation angle of the precession axis, the opening angle of the precession cone and the flow velocity. This description is appropriate for outflows with v/c ≤ 0 . 5. azul). En t´erminos de un modelo de jet precesante bal´ıstico, mostramos que para un intervalo de par´ametros del flujo estos efectos relativistas corresponden a cambios aparentes en: la orientacion del eje de precesi´on, el ´angulo de apertura del cono de precesi´on y la velocidad del flujo. Esta descripci´on es apropiada para flujos con v/c ≤ 0 . 5.