William Henry Matthaeus | |
---|---|
Nationality | American |
Education | University of Pennsylvania (B.A.) Old Dominion University (M.A.) College of William and Mary (M.S., Ph.D.) |
Awards | |
Scientific career | |
Fields | Plasma physics |
Thesis | Nonlinear Evolution of the Magnetohydrodynamic Sheet Pinch (1979) |
Doctoral advisor | David Campbell Montgomery |
Website | web |
William Henry Matthaeus (born 1951) is an American astrophysicist and plasma physicist. He is known for his research on turbulence in magnetohydrodynamics (MHD) (e.g. numerical simulations and kinetic theory) [1] [2] [3] [4] and astrophysical plasmas (e.g. solar wind and its fluctuations), [5] [6] [7] [8] [9] [10] for which he was awarded the 2019 James Clerk Maxwell Prize for Plasma Physics. [11]
Matthaeus graduated from the University of Pennsylvania with a bachelor's degree in physics and philosophy in 1973 on a scholarship from the Mayor of Philadelphia. In 1975, he received an M.A. in physics at Old Dominion University in Norfolk, Virginia, and then received an M.S. in physics and Ph.D in physics at the College of William and Mary in 1977 and 1979 respectively. [11] His thesis was on "Nonlinear Evolution of the Magnetohydrodynamic Sheet Pinch" and he was supervised by David Campbell Montgomery. [12] Since 1983, he has been affiliated with the Bartol Research Institute and is currently Unidel Professor of Physics and Astronomy at the University of Delaware. [13]
Matthaeus is involved in the Swarthmore Spheromak experiment and since 2004 has been significantly involved in the Parker Solar Probe, launched in 2018, [14] to study the corona of the sun. He has been director of NASA's Delaware Space Grant since 2016. [15]
In the 1990s, Matthaeus applied the Lattice Boltzmann method to magnetohydrodynamics [16] and in 1992, published a well-cited paper showing that it was possible to recover the Navier-Stokes equation by using the Lattice Boltzmann method. [17]
In 1985, Matthaeus received the James B. MacElwane Award from the American Geophysical Union [18] and became its fellow. He was then elected a fellow of the American Physical Society in 1998. [19]
In 2019, he received the James Clerk Maxwell Prize for Plasma Physics for "pioneering research into the nature of turbulence in space and astrophysical plasmas, which has led to major advances in understanding particle transport, dissipation of turbulent energy, and magnetic reconnection ". [11]
Magnetohydrodynamics is a model of electrically conducting fluids that treats all interpenetrating particle species together as a single continuous medium. It is primarily concerned with the low-frequency, large-scale, magnetic behavior in plasmas and liquid metals and has applications in numerous fields including geophysics, astrophysics, and engineering.
In plasma physics, an Alfvén wave, named after Hannes Alfvén, is a type of plasma wave in which ions oscillate in response to a restoring force provided by an effective tension on the magnetic field lines.
In plasma physics, magnetic helicity is a measure of the linkage, twist, and writhe of a magnetic field. In ideal magnetohydrodynamics, magnetic helicity is conserved. When a magnetic field contains magnetic helicity, it tends to form large-scale structures from small-scale ones. This process can be referred to as an inverse transfer in Fourier space.
Magnetic reconnection is a physical process occurring in electrically conducting plasmas, in which the magnetic topology is rearranged and magnetic energy is converted to kinetic energy, thermal energy, and particle acceleration. Magnetic reconnection involves plasma flows at a substantial fraction of the Alfvén wave speed, which is the fundamental speed for mechanical information flow in a magnetized plasma.
Cluster II is a space mission of the European Space Agency, with NASA participation, to study the Earth's magnetosphere over the course of nearly two solar cycles. The mission is composed of four identical spacecraft flying in a tetrahedral formation. As a replacement for the original Cluster spacecraft which were lost in a launch failure in 1996, the four Cluster II spacecraft were successfully launched in pairs in July and August 2000 onboard two Soyuz-Fregat rockets from Baikonur, Kazakhstan. In February 2011, Cluster II celebrated 10 years of successful scientific operations in space. In February 2021, Cluster II celebrated 20 years of successful scientific operations in space. As of March 2023, its mission has been extended until September 2024. The China National Space Administration/ESA Double Star mission operated alongside Cluster II from 2004 to 2007.
In magnetohydrodynamics (MHD), shocks and discontinuities are transition layers where properties of a plasma change from one equilibrium state to another. The relation between the plasma properties on both sides of a shock or a discontinuity can be obtained from the conservative form of the MHD equations, assuming conservation of mass, momentum, energy and of .
An ionization instability is any one of a category of plasma instabilities which is mediated by electron-impact ionization. In the most general sense, an ionization instability occurs from a feedback effect, when electrons produced by ionization go on to produce still more electrons through ionization in a self-reinforcing way.
Adolfo Figueroa Viñas is the first Puerto Rican astrophysicist at the National Aeronautics and Space Administration (NASA) and is an expert in solar and space plasma physics at the Heliophysics Science Division. As a staff scientist his research interests include studying plasma kinetic physics and magnetohydrodynamics of the solar wind, heliosphere, shock waves, MHD and kinetic simulation of plasma instabilities, and turbulent processes associated with space, solar and astrophysical plasmas.
Magnetohydrodynamic turbulence concerns the chaotic regimes of magnetofluid flow at high Reynolds number. Magnetohydrodynamics (MHD) deals with what is a quasi-neutral fluid with very high conductivity. The fluid approximation implies that the focus is on macro length-and-time scales which are much larger than the collision length and collision time respectively.
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Hartmut Zohm is a German plasma physicist who is known for his work on the ASDEX Upgrade machine. He received the 2014 John Dawson Award and the 2016 Hannes Alfvén Prize for successfully demonstrating that neoclassical tearing modes in tokamaks can be stabilized by electron cyclotron resonance heating, which is an important design consideration for pushing the performance limit of the ITER.
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Guy Laval is a French physicist, professor at the École polytechnique and member of the French Academy of Sciences.
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Toshiki Tajima is a Japanese theoretical plasma physicist known for pioneering the laser wakefield acceleration technique with John M. Dawson in 1979. The technique is used to accelerate particles in a plasma and was experimentally realized in 1994, for which Tajima received several awards such as the Nishina Memorial Prize (2006), the Enrico Fermi Prize (2015), the Robert R. Wilson Prize (2019), the Hannes Alfvén Prize (2019) and the Charles Hard Townes Award (2020).
Hudong Chen is a physicist.
James Wynne "Jim" Dungey (1923–2015) was a British space scientist who was pivotal in establishing the field of space weather and made significant contributions to the fundamental understanding of plasma physics.