Non-constant superluminal velocities in AGN.

摘要: Large apparent superluminal velocities are observed in nuclear jets Active Galaxies, indicating the presence of relativistic almost along line sight. If flow is well collimated, as suggested by large scale radio structure, inferred alignment leads to difficulties with source statistics. Here a modification usual beam model proposed, which jet assumed contain azimuthal (swirling) flow. Perturbation analysis used show that unstable Kelvin-Helmholtz helical standing wave, wavelength increases without bound limit vanishing swirl. This instability may cause cylindrical follow path space, thereby reducing implied source, and providing natural interpretation non-constant velocities.