atoms Review Interrelationship between Lab, Space, Astrophysical, Magnetic Fusion, and Inertial Fusion Plasma Experiments Mark E. Koepke Department of Physics and Astronomy, West Virginia University, Morgantown, WV 26506-6315, USA; [email protected]; Tel.: +1-304-293-4912 Received: 1 December 2018; Accepted: 3 February 2019; Published: 11 March 2019 Abstract: The objectives of this review are to articulate geospace, heliospheric, and astrophysical plasma physics issues that are addressable by laboratory experiments, to convey the wide range of laboratory experiments involved in this interdisciplinary alliance, and to illustrate how lab experiments on the centimeter or meter scale can develop, through the intermediary of a computer simulation, physically credible scaling of physical processes taking place in a distant part of the universe over enormous length scales. The space physics motivation of laboratory investigations and the scaling of laboratory plasma parameters to space plasma conditions, having expanded to magnetic fusion and inertial fusion experiments, are discussed. Examples demonstrating how laboratory experiments develop physical insight, validate or invalidate theoretical models, discover unexpected behavior, and establish observational signatures for the space community are presented. The various device configurations found in space-related laboratory investigations are outlined. Keywords: laboratory plasma; astrophysical plasma; fusion plasma; lasers; stars; extragalactic objects; spectra; spectroscopy; scaling laws 1. Introduction Many advances in understanding geospace, heliospheric, and astrophysical plasma phenomena are linked to insight derived from theoretical modeling and/or laboratory plasma experiments [1–3]. Geospace plasma physics includes space weather during periods of magnetic storms, substorms, and geomagnetic quiet; nonlinear plasma behavior such as structure evolution in turbulence and particle transport, fluid and kinetic instabilities, wave–particle interactions, ionospheric-magnetospheric-auroral coupling; solar-wind interaction with magnetospheres; and solar-corona heating. Heliospheric physics is concerned with investigating the interaction of the Sun’s heliosphere with the local interstellar medium, as well as with the origin and evolution of the Sun and solar wind, the magnetospheres of the Earth and outer planets, and low-energy cosmic rays. High-energy (HE) and high-energy-density (HED) astrophysics is the study of electromagnetic radiation, from ultra-energetic cosmic phenomena ranging from black holes to the Big Bang, and of ionized matter at ultra-high pressure (~1 Mbar to 1000 Gbar, i.e., 1 million to 1 trillion Earth-surface atmospheres of pressure), density, and temperature (i.e., stored energy in matter >1010 J/m3, e.g., solid-density material at 10,000 K (~1 eV)) for which observations are made in the extreme-ultraviolet (EUV), X-ray, and gamma-ray bands. Examples of places where these HED conditions occur are in Earth’s, Jupiter’s, and Sun’s core and inside igniting Inertial Confinement Fusion (ICF) implosions (~250 Gbar). Figure1 illustrates the wide ranges of density and temperature naturally occurring in geospace, in the heliosphere, and in astrophysical environments and artificially occurring in larger magnetic and inertial fusion devices, as well as in smaller university-scale laboratory devices. Atoms 2019, 7, 35; doi:10.3390/atoms7010035 www.mdpi.com/journal/atoms Atoms 2019, 7, 35 2 of 10 Atoms 2018, 6, x FOR PEER REVIEW 2 of 9 (a) (b) FigureFigure 1. 1. TypicalTypical parameters parameters of of lab lab an andd nature’s nature’s plasmas: plasmas: Cartesian Cartesian representation representation of of density density and and temperaturetemperature range range associated associated with with (a ()a heliospheric) heliospheric (10 (102 –2 –10109 9K)K) [2] [2 and] and (b ()b astrophysical) astrophysical (10 (102 –2 –10101414 K)K) plasmaplasma [4]. [4]. Upper-right Upper-right region region corresponds corresponds to to pu pushingshing parameters parameters toward toward nuclear nuclear fusion fusion ignition. ignition. 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AdvancesAdvances for for which which (a) (a) lab lab experiments experiments helped helped explain explain phenomena phenomena and and processes, processes, (b) (b) lab lab data data influencedinfluenced the the interpretation interpretation of of space space data, data, and and (c) (c) laboratory laboratory validation validation of of atomic atomic and and molecular molecular spectroscopicspectroscopic processes processes contributed contributed to telescopictelescopic probingprobing of of distant distant events events are are itemized itemized in Sectionsin sections2–4 . 2–4.As identifiedAs identified in the in Plasma the Plasma 2010 report2010 report of the Nationalof the National Academies Academies [5], six critical[5], six plasma critical processesplasma processesdefine the define research the frontier.research frontier. • Explosive instability in plasmas • Explosive instability in plasmas • Multiphase plasma dynamics • •Multiphase Particle acceleration plasma dynamics and energetic particles in plasmas • •Particle Turbulence acceleration and transport and energetic in plasmas particles in plasmas • Magnetic self-organization in plasmas Atoms 2019, 7, 35 3 of 10 • Turbulence and transport in plasmas • Magnetic self-organization in plasmas Atoms 2018, 6, x FOR PEER REVIEW 3 of 9 • Correlations in plasmas • Correlations in plasmas High High Density Energy Laser-Driven, Heavy-Ion, Magneto-Inertial Shocks and Enhanced-Performance Extreme Fields Equation of State andTransport Materials Planets--Stars--Black Holes Planets--Stars--Black HEDLP/IFE Warm Warm Dense Realm of Plasma Matter Science Frontiers Lab Astro Low Temperature