Hydrodynamic Collimation of Yso Jets
نویسندگان
چکیده
We present the results of numerical hydrodynamic models for the collimation of outflows from young stellar objects. We show that the presence of a toroidal environment can lead to efficient formation of jets and bipolar outflows from initially uncollimated central winds. The interaction between the wind and the environment leads to two types of collimation, one which is dominated by radiative cooling effects, and one which works when cooling is less efficient. We describe the two types of jets as they appear in the simulations and we suggest a description for the long term evolution of these structures in more realistic time-dependent wind sources.
منابع مشابه
Outflow collimation in young stellar objects
In this paper we explore the effect of radiative losses on purely hydrodynamic jet collimation models applicable to Young Stellar Objects (YSOs). In our models aspherical bubbles form from the interaction of a central YSO wind with an aspherical circumprotostellar density distribution. Building on a previous non-radiative study (Frank & Mellema 1996) we demonstrate that supersonic jets are a na...
متن کاملYSO Jets and Molecular Outflows: Tracing the History of Star Formation
Collimated outflows from Young Stellar Objects (YSOs) can be seen as tracers of the accretion powered systems which drive them. In this paper I review some theoretical and observational aspects of YSO outflows through the prism of questions relating to the protostellar source. The issue I address is: can collimated outflows be used as “fossils” allowing the history of protostellar evolution to ...
متن کاملEffects of Cooling on the Propagation of Magnetized Jets
We present multi-dimensional simulations of magnetized radiative jets appropriate to Young Stellar Objects. Magnetized jets subject to collisionally excited radiative losses have not, as yet, received extensive scrutiny. The purpose of this letter is to articulate the propagation dynamics of radiative MHD jets in the context of the extensive jet literature. Most importantly, we look for morphol...
متن کاملHydrodynamical Models of Outflow Collimation in YSOs
– 2 – In this paper we explore the physics of time-dependent hydrodynamic collimation of jets from Young Stellar Objects (YSOs). Using parameters appropriate to YSOs we have carried out high resolution hydrodynamic simulations modeling the interaction of a central wind with an environment characterized by a toroidal density distribution which has a moderate opening angle of θ ρ ≈ 90 o The resul...
متن کاملDiscovery of synchrotron emission from a YSO jet
Synchrotron emission at radio wavelengths is commonly found in relativistic jets from active galactic nuclei (AGNs) and microquasars and allows the study of the magnetic field in these kind of jets. In contrast, the radio emission from jets from young stellar objecs (YSOs) is usually of very different nature: thermal free-free emission, which does not provide direct information about their magn...
متن کامل