Exploring astrophysics-relevant magnetohydrodynamics with pulsed-power laboratory facilities

Abstract

Laboratory facilities employing high pulsed currents and voltages, and called generally "pulsed-power facilities", allow experimenters to produce a variety of hydrodynamical structures replicating, often in a scalable fashion, a broad range of dynamical astrophysical phenomena. Among these are: astrophysical jets and outflows, astrophysical blast waves, magnetized radiatively dominated flows and, more recently, aspects of simulated accretion disks. The magnetic field thought to play significant role in most of the aforementioned objects is naturally present and controllable in pulsed-power environments. The size of the objects produced in pulsed-power experiments ranges from a centimeter to tens of centimeters, thereby allowing the use of a variety of diagnostic techniques. In a number of situations astrophysical morphologies can be replicated down to the finest structures. The configurations and their parameters are highly reproducible; one can vary them to isolate the most important phenomena and thereby help in developing astrophysical models. This approach has emerged as a useful tool in the quest to better understand magnetohydrodynamical effects in astronomical environments. The present review summarizes the progress made during the last decade and is designed to help readers identify and, perhaps, implement new experiments in this growing research area. Techniques used for generation and characterization of the flows are described. 1 Retired 2 CONTENTS I. Introduction II. Jets and outflows-weak magnetic field A. Generating plasma streams and plasma jets with wire arrays. B. Hypersonic, radiatively cooled hydrodynamic jets and their interaction with the ambient medium C. Hydrodynamic interaction of the jets with a side wind D. Highly-collimated jets produced by ablation of the central area of a metal foil III. Jets and outflows-significant magnetic field A. Magnetically-dominated tower jets B. Formation of energetic ions in a magnetic cavity C. Possible role of axial magnetic field B. Episodic events and internal shocks E. Magnetic arches and their stability F. MHD equilibria stabilized by the shear flow IV. Rotating plasmas-on the way to imitating the accretion discs V. Shock waves A. General comments B. Blast waves and radiative precursors C. Shocks in the colliding streams D. Introducing magnetic field E. Interaction of magnetized streams with clumps and globules VI. Non-MHD effects A. Hall and other two-fluid effects B. Generation of energetic particles C.

Interactions of magnetized plasma flows in pulsed-power driven experiments

“…When using an external magnetic field for this task, there must be sufficient time for the field to penetrate into and couple to the plasma before the intended interactions of the flow take place [7,8].…”

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

“…Despite the similarity of the Mather-type PF geometry to coaxial plasma accelerators (Marshall guns), the mechanism for generating plasma flow is more like the mechanism observed in conical wire arrays (Lebedev et al . 2019). A plasma flow is formed in the pinch region with a diameter of approximately 1 cm and 5–10 cm long.…”

“…In particular, significant progress was achieved on the MAGPIE facility (Imperial College London, UK). In the series of experiments performed at this facility, the rotation effects detected in protostellar jets were modelled in the laboratory, the interaction of high-speed radiation-cooled jets with the environment were modelled and possible mechanisms of the jet formation have been elucidated among other results (Lebedev, Frank & Ryutov 2019). Interesting results were also obtained on a high-power laser in the LULI laboratory (Ecole Polytechnique, Paris, France), where it was shown that applying a poloidal magnetic field can provide effective collimation of the plasma flow (Albertazzi et al 2014).…”

“…Then the pinch is destroyed as a result of the development of magnetohydrodynamic (MHD) instabilities, and the appearance of anomalous resistance leads to a jump in voltage (figure 1c) and to a redistribution of current into the interelectrode region, mainly in the proximity to the insulator. Despite the similarity of the Mather-type PF geometry to coaxial plasma accelerators (Marshall guns), the mechanism for generating plasma flow is more like the mechanism observed in conical wire arrays (Lebedev et al 2019). A plasma flow is formed in the pinch region with a diameter of approximately 1 cm and 5-10 cm long.…”

Analytic Model for the Time-dependent Electromagnetic Field of an Astrophysical Jet

“…Astrophysical jets have been simulated in laboratory experiments using pulsed power technology by Hsu & Bellan (2002), Lebedev et al (2005), You et al (2005), Gourdain & Seyler (2014), and Lavine & You (2019). Experiments simulating astrophysical jets using pulsed power have been reviewed by Lebedev et al (2019), and experimental observations have been reproduced using 3D MHDnumerical codes by Ciardi et al (2007), Huarte-Espinosa et al (2013), and Zhai et al (2014). Li et al (2016) have simulated astrophysical jets in a laboratory experiment that used a high-power laser.…”