Are Quasar Jets Matter or Poynting Flux Dominated?

Marek Sikora; Greg M. Madejski; Jean-Pierre Lasota; Mitchell C. Begelman

doi:10.1063/1.2141855

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Are Quasar Jets Matter or Poynting Flux Dominated?

Marek Sikora·Greg M. Madejski·Jean-Pierre Lasota·Mitchell C. Begelman

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Abstract

If quasar jets are accelerated by magnetic fields but terminate as matter dominated, where and how does the transition occur between the Poynting-dominated and matter-dominated regimes? To address this question, we study constraints which are imposed on the jet structure by observations at different spatial scales. We demonstrate that observational data are consistent with a scenario where the acceleration of a jet occurs within 10^{3-4} R_g. In this picture, the non-thermal flares -- important defining attributes of the blazar phenomenon - are produced by strong shocks formed in the region where the jet inertia becomes dominated by matter. Such shocks may be formed due to collisions between the portions of a jet accelerated to different velocities, and the acceleration differentiation is very likely to be related to global MHD instabilities.

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Marek Sikora, Greg M. Madejski, Jean-Pierre Lasota, Mitchell C. Begelman. 2005-09-22. Are Quasar Jets Matter or Poynting Flux Dominated?. https://doi.org/10.1063/1.2141855

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