Laboratory simulation of astrophysical jets within facilities of plasma focus type

Abstract

A laboratory simulation of astrophysical processes is one of the intensively developed areas of plasma physics. A new series of experiments has been launched recently on the Plasma Focus type facility in NRC Kurchatov Institute. The main goal is to study the mechanisms of the jet stabilization, due to which it can propagate at distances much greater than their transverse dimensions. The experiments with stationary gas filling revealed regimes in which a narrowly collimated plasma jet was formed, the head of which was no wider than several centimeters at jet propagation distances of up to 100 cm. The PF-1000 (IFPiLM, Warsaw, Poland) and KPF-4 (SFTI, Sukhum, Abkhazia) experiments are aimed at creating profiled initial gas distributions to control the conditions of plasma jet propagation in the ambient plasma. Estimations of the dimensionless parameters, i.e. the Mach, Reynolds, and Peclet numbers which were achieved during the experiments, showed that the PF-facilities can be used for the YSO jets modelling. The future experiments, which can allow one to understand the nature of the stable plasma ejections observed in many astrophysical sources, are discussed.

Properties of toroidal magnetic fields in axial plasma flow on the PF-1000U plasma focus facility

“…Indications were also found that current closure occurs on the periphery of the flow itself (Krauz et al 2019). Finally, the morphology of the areas of interaction between the plasma ejections and the working gases filling the chamber was indeed close to the structure of the characteristic regions observed both in non-relativistic (Herbig-Haro objects) and relativistic (so-called radio lobes) astrophysical objects (Beskin et al 2017a;Krauz et al 2017Krauz et al , 2018. Therefore, it seems extremely important to conduct further detailed studies to clarify the role of the external environment and the details of the structure in the areas of interaction with the external environment.…”

“…Devices of the 'plasma focus' (PF) type (Filippov, Filippova & Vinogradov 1962;Mather 1965) appear to be very promising to achieve this goal. PF facilities are known as sources of intense plasma flows, which are widely used in various fields, including the modelling of astrophysical processes (Mourenas et al 2003;Beskin et al 2017a;Krauz, Beskin & Velikhov 2018).…”

“…2017 a ; Krauz et al. 2017, 2018). Therefore, it seems extremely important to conduct further detailed studies to clarify the role of the external environment and the details of the structure in the areas of interaction with the external environment.…”

The Collimated Propagation Causes of Astrophysical and Laboratory Jets

“…For laboratory modeling of the jet propagation in the vicinity of a young star, both the spatial scale of the stream and the presence of the ambient environment are essential factors. It is possible to implement these conditions with the PF-3 facility ("plasma focus," Kurchatov Institute) [10,11], which makes it possible to simulate the interaction of astrophysical jets with the surrounding matter in the laboratory. In this case, due to the rather large size of the resulting jets, we can measure not only the thermodynamic and kinematic characteristics, but also, using magnetic probes, the magnitude and structure of magnetic fields.…”

Internal Structure of the Jets from Young Stars Simulated at Plasma Focus Facilities

“…One more promising direction of laboratory research on jets is associated with the plasma focus technology. These studies were begun several years ago at the National Research Center "Kurchatov Institute" at the PF-3 facility (Krauz et al 2015(Krauz et al , 2018Mitrofanov et al 2017) and were then continued at the Institute of Plasma Physics and Laser Fusion (the PF-1000 facility,Warsaw) and the KPF-4 "Phoenix" facility at the Sukhum Physical-Technical Institute . A large volume of data concerning the internal structure of the plasma jet was also accumulated here.…”