This talk will be a review of the principle space and astrophysical plasma relevant experiments undertaken at Wisconsin Plasma Physics Laboratory (WiPPL) since the last IPELS meeting. WiPPL is a collaborative user facility, operating the Big Red Ball (BRB) and the Madison Symmetric Torus (MST) out of the Physics Department at the University of Wisconsin, hosting users from around the world. I...
Ambipolar electric fields are often observed in compressed plasma layers throughout the near-Earth space environment and have been shown to be important for plasma flows, wave generation, broadband turbulence, and dissipation mechanisms. When an ambipolar electric field self-consistently forms perpendicular to a background magnetic field, EรB velocity shear is generated. Shear-driven...
The standard magnetorotational instability (SMRI) has been regarded as the most promising instability responsible for the turbulence required to explain the fast accretion observed across the Universe. However, unlike other fundamental plasma processes such as Alfvรฉn waves and magnetic reconnection, which have been subsequently detected and studied in space and the laboratory, SMRI remains...
The number of satellites launched into low Earth orbit (LEO) is increasing at an exponential rate. Launches support deployment of multi-satellite constellations for many applications. In situ experiments with the Canadian Swarm-E Satellite have been conducted to better locate the positions of satellites and space debris for prevention of collisions.
Currently, there are about 27,000 known...
During transient instabilities in a 2โeV, highly collisional MHD-driven plasma jet experiment, evidence of a 6โkeV electron tail was observed via x-ray measurements. The cause for this unexpected high energy tail is explored using numerical simulations of the Rutherford scattering of a large number of electrons and ions in the presence of a uniform electric field that is abruptly turned on as...
Magnetic reconnection is a ubiquitous fundamental process in space and astrophysical plasmas that rapidly converts magnetic energy into some combination of flow energy, thermal energy, and non-thermal energetic particles. Over the past decade, a new experimental platform has been developed to study magnetic reconnection using strong coil currents powered by high power lasers at low plasma...
Mini-magnetospheres are ion-scale structures that are ideal for studying the kinetic-scale physics of collisionless space plasmas. Such ion-scale magnetospheres can be found on local regions of the Moon, associated with the interaction of the solar wind with the lunar crustal magnetic field. In this work, we report on the experimental study of magnetic reconnection in laser-driven lunar-like...
In two toroidal plasma merging experiments with high guide field ($B_{t}$ >> $B_{p}$), the ion heating energy by magnetic reconnection is shown to scale with the reconnecting magnetic energy ($B_{rec}^{2}$/2$\mu_{0}$) where $B_{rec}$~$B_{p}$. This $B_{rec}^{2}$- scaling of ion heating energy by reconnection can be understood by the fact that in the reconnection downstream the ion energy is...
In a prototypical two-dimensional antiparallel reconnection geometry, we experimentally verify a well- known Petshek-type reconnection layer of double wedge structure and explained by two-fluid dynamics. In a two-fluid reconnection layer, as electrons and ions move into the reconnection layer with different paths, the magnetized electrons penetrate deep into the reconnection layer generating a...
Shock waves are ubiquitous in astrophysical, space and laboratory plasmas and often include an embedded, dynamically significant magnetic field. This magnetic field modifies the RH shock jump conditions, and allows dissipation mechanisms specific to magneto-hydrodynamics, such as Ohmic heating, to contribute to shock shaping. In fact, low Mach number shocks can be shaped exclusively by...
Alfvรฉnic turbulence is pervasive in the solar wind and thought to be common in space and astrophysical plasmas. The solar wind has allowed us to learn much about this turbulence, however, there are many open questions about how it works and shapes these systems. Lab experiments provide a controlled environment to test the basic physics of such turbulence. Here, we present an experiment on the...
We have recently introduced a new concept for rocket thrusters that exploit the mechanism behind solar flares, where magnetic energy is converted to kinetic energy through the process of magnetic reconnection. Inspired by the studies of fundamental processes in helicity injection experiments in NSTX, computer simulations (in both single and two-fluid extended MHD models) were used for the...
The Universe was born without magnetic fields, yet in the modern Universe dynamically important magnetic fields are ubiquitous. The standard model of magnetogenesis explains this with small-scale dynamo (SSD) amplification of weak primordial fields to the levels we see today, followed by larger-scale coherence generated through large-scale dynamos (LSDs). This model, however, faces challenges...
Electron-scale physics is often the key ingredient that helps to disentangle complex plasma measurements. In this talk, I highlight the synergies between in-situ observations, simulation models and laboratory experiments, characterizing the role that localized plasma processes can have in regulating the large-scale dynamics and evolution of a macroscopic system. I focus on modeling the kinetic...
We found by three-dimensional global radiation magnetohydrodynamic simulations that during the hard-to-soft state transition observed in stellar mass black hole candidates and in active galactic nuclei, toroidal magnetic field is amplified around the interface between the hard X-ray emitting hot accretion flow near the black hole and the radiatively cooled outer disk. Since the magnetic...
The presence of charged dust particles in the space environment is well-known. From observations of structures in the dust tails of comets and the Voyager observations of radial structures (โspokesโ) in Saturnโs rings, the role of charged dust in the solar system has been the subject of intense study for decades. More recently, the presence of flowing magnetized dust clouds has been...
Steep pressure gradients in a magnetized plasma can induce a variety of spontaneous low frequency excitations such as drift-Alfven waves and vortices. We present results from basic experiments on energy and particle transport in magnetized plasmas with multiple heat sources in close proximity [1]. The experiments were carried out at the upgraded Large Plasma Device (LAPD) operated by the Basic...
In earlier papers (Sauer and Sydora, 2015, 2016) it has been shown that an electron current in a plasma is directly linked to the formation of Langmuir oscillations at the electron plasma frequency ฯ_e. The current may arise due to a relative drift between electrons and protons or by a drifting electron population. No kind of beam instability should be involved. The excitation of ...
The Juno satellite is the first satellite in polar orbit around Jupiter, leading to unprecedented coverage of Jupiterโs magnetosphere. During the Juno extended mission, the satellite samples the polar regions of Jupiter at altitudes of less than 0.5 Jovian radii. Observations from Juno have indicated very low densities, as low as 10โ3 cmโ3, on polar cap field lines at Jupiter (Sulaiman et...
Collisionless low Mach number shocks are abundant in astrophysical and space plasma environments, exhibiting complex wave activity and wave-particle interactions. In this paper, we present 2D Particle-in-Cell simulations of quasi-perpendicular nonrelativistic (Vsh=(5500-22000) km/s) low Mach number shocks, with a specific focus on studying electrostatic waves in the shock ramp and the...
The magnetic Rayleigh Taylor instability (MRTI) is ubiquitous in a wide range of astrophysical and laboratory systems. However, the evolution and the dynamics of MRTI is not fully understood. Magnetic fields play a crucial role in the instability dynamics of these systems. Towards understanding the interplay between gravity and magnetic forces on the evolution of instability, we study MRTI...
Although turbulent dynamo processes can amplify magnetic fields to the strength observed in astrophysical situations, how seed magnetic fields are generated in the first place is still a mystery. We show that by analyzing the evolution of canonical vorticity that the canonical battery effect is responsible for seed magnetogenesis. The process generalizes popular magnetogenesis mechanisms,...
We carried out a high-resolution simulation of the solar convection zone and, for the first time, reproduced the solar-like differential rotation without using any manipulation.
The sun rotates differentially with the fast equator and the slow poles, called solar-like differential rotation (DR). The DR is thought to be maintained by the turbulent thermal convection in the convection zone, but...
