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The Equatorial Outflow of SS433

Z. Paragi·I. Fejes·R. C. Vermeulen·R. T. Schilizzi·R. E. Spencer·A. M. Stirling
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Abstract

We present VLBI imaging results for SS433 from the period 1995-2000. An equatorial emission region is detected and confirmed in 7 experiments at 1.6 and 5 GHz. The structure of the region changes with time on scales of weeks to months. The nature of emission is unknown, but it is certainly non-thermal, maybe optically thin synchrotron. The spectrum however might be attenuated by a thermal population of electrons. There were previous indications for an equatorial outflow from the system. We do detect outward motion of a radio component, and estimate a speed of 1200/sin(i) km/s. Theoretical work and IR observations suggest that the mass-loss rate in SS433 is much higher in this region than in the jets. We suggest that the high-mass microquasars might all have equatorial outflows; in fact, it is the dominant form of mass-loss in these systems.

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Z. Paragi, I. Fejes, R. C. Vermeulen, R. T. Schilizzi, R. E. Spencer, A. M. Stirling. 2002-07-03. The Equatorial Outflow of SS433. https://arxiv.org/abs/astro-ph/0207061

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