University of Minnesota
School of Physics & Astronomy
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Robert Lysak

Professor (Minnesota Institute for Astrophysics)

AMUNDH 383 (office), 625-1323
lysak @ physics.umn.edu • http://ham.space.umn.edu/~bobcurriculum vitae

Lysaknew.jpg

Director of Graduate Studies, School of Physics and Astronomy, 1995-2001. Editor, Symposium on “Alfvénic Structures: From the Sun to the Magnetosphere,” Advances in Space Research, 2001; Member, National Academy of Sciences, Solar and Space Physics Survey; Panel on Magnetosphere-Ionosphere-Atmosphere, 2001; Chapman Conference Chair, American Geophysical Union, 2002-2006; Convener, Winckler Symposium: Fast time variations of auroral particle participation, Minneapolis, April, 2004; Convener, Symposium on “Electrodynamics of Aurora,” 2005 IAGA Scientific Assembly, Toulouse, France, July, 2005; Convener, Symposium on “Nonlinear and Kinetic Physics of ULF and VLF Waves,” AGU Fall Meeting, San Francisco, 2005; Best Dissertation Award Committee, Graduate School, 2005-08. Graduate School Fellowship Committee, member; 2006-08; co-chair, 2008-10; co-editor, Magnetospheric ULF Waves: Synthesis and New Directions, AGU Monograph 169, 2006; Co-convener, Symposium on “Ionosphere-Magnetosphere Coupling and Auroral Particle Acceleration, 36th COSPAR Scientific Assembly; Beijing, China, July, 2006; Co-director, School on “Turbulence and Waves in Space Plasmas,” International School of Space Science, L’Aguila, Italy, September, 2007. Main Scientific Organizer, Symposium on “Ionosphere-Magnetosphere Coupling: The Role of Alfvén Waves in Auroral Processes,” 37th COSPAR Scientific Assembly, Montreal, July, 2008; American Geophysical Union Fellow, 2011; Member, Geospace Environmental Modeling Steering Committee, 2010-present; Senior Editor, Journal of Geophysical Research-Space Physics, 2010-2013.

Summary of Interests
Theoretical Space Plasma Physics, especially magnetospheric physics; auroral particle acceleration; dynamics of ultra-low-frequency (ULF) waves in the magnetosphere, especially kinetic Alfven waves; magnetosphere-ionosphere coupling; dynamics of field-ali

About My Work

My research emphasizes a fundamental theoretical understanding of the dynamics of plasmas in the Earth's magnetosphere, as well as in other planetary magnetospheres, the solar wind, and other astrophysical environments. I am particularly interested in the dynamics of the Earth's auroral regions. In these regions, strong currents flow along the magnetic field ("field-aligned currents") that are dissipated in the ionosphere and by accelerating the particles that produce the aurora. Changes in these current systems are mediated by waves called Alfven waves, which correspond to transverse fluctuations of the geomagnetic field. Although Alfven waves were first studied using magnetohydrodynamic (MHD) theory, I have approached them using a more complete kinetic theory; thus, these waves are sometimes called kinetic Alfven waves. Such waves can directly accelerate electrons into the ionosphere to produce the aurora. In addition, we are studying the ways in which these waves can evolve into quasi-static parallel electric fields that are known to be associated with discrete auroral arcs. These studies lead to an overall understanding of ultra-low-frequency (ULF) waves in the magnetosphere, especially the eigenmodes that can form due to the inhomogeneous nature of the magnetospheric plasma. Parallel electric fields are also necessary for the process called magnetic reconnection, which refers to the reorganization of the magnetic topology in thin current sheets. We study the dynamics of these processes as well. ULF waves are also important in Jupiter's magnetosphere, where they are driven by the motion of Jupiter's moon Io. Alfven waves may also be responsible for processes in the solar corona, such as solar flares, coronal mass ejections, and the heating of the corona to millions of degrees.

This work also benefits from collaboration with Senior Researcher Dr. Yan Song. Her work emphasizes the fundamental theory of particle acceleration and magnetic reconnection, emphasizing a dynamical approach that improves upon the quasi-steady descriptions often used to discuss these phenomena.

Lysak revised Figure 2.jpg

(a) Electric and (b) magnetic field perturbations for a numerical model of waves trapped in the ionospheric Alfven resonator (IAR) in an overall perpendicular density gradient. Interference between upgoing and downgoing waves leads to structuring of these waves, and the resonances of the IAR modes can be seen in the results (Lysak and Song, 2011).

Selected Publications

Lysak, R. L., Y. Song, M. D. Sciffer, and C. L. Waters (2015), Propagation of Pi2 pulsations in a dipole model of the magnetosphere, J. Geophys. Res. Space Physics, 120, DOI:10.1002/2014JA020625

Lysak, R. L., Comment on “Improved basis set for low frequency plasma waves” by P. M. Bellan, J. Geophys. Res. Space Physics, 118, doi: 10.1002/jgra.50315 (2013)

Waters, C. L., R. L. Lysak and M. D. Sciffer, On the coupling of fast and shear Alfvén wave modes by the ionospheric Hall conductance, Earth, Planets, Space., 65, 385-396 (2013)

R. L. Lysak, C. L. Waters, and M. D. Sciffer, Modeling of the ionsopheric Alfvén resonator in dipolar geometry, J. Geophys. Res. Space Physics, 118, doi: 10.1002/jgra.50090 (2013)

Lysak, R. L., and Y. Song, Development of parallel electric fields at the plasma sheet boundary layer, J. Geophys. Res., 116, A00K14, doi:10.1029/2010JA016424 (2011)

Woodroffe, J. R., and R. L. Lysak, Ultra-low frequency wave coupling in the ionospheric Alfvén resonator: Characteristics and implications for the interpretation of ground magnetic fields, J. Geophys. Res., 117, A03223, doi:10.1029/2011JA017057 (2012)

N. Lin, H. Frey, S. Mende, F. Mozer, R. Lysak, Y. Song and V. Angelopoulos, Statistical study of substorm timing sequence, J. Geophys. Res., 114, A12204, doi: 10.1029/2009JA14381, 2009

R. L. Lysak, Y. Song, and T. W. Jones, Propagation of Alfvén waves in the magnetotail during substorms, Ann. Geophys., 27, 2237, 2009

R. L. Lysak and Y. Song, Propagation of kinetic Alfvén waves in the ionospheric Alfvén resonator in the presence of density cavities, Geophys. Res. Lett., 35, L20101, doi:10.1029/2008GL035728, 2008

R. L. Lysak, On the dispersion relation for the kinetic Alfvén wave in an inhomogeneous plasma, Phys. Plasmas, 15, 062901, 2008

Lysak, R. L., and A. Yoshikawa, Resonant cavities and waveguides in the ionosphere and atmosphere, Magnetospheric ULF Waves, K. Takahashi et al. (eds.), AGU Monograph Series, American Geophysical Union, Washington, p. 289, 2006. [abstract] [download Lysak waveguide paper final.pdf]

R. L. Lysak and Y. Song, Magnetosphere-ionosphere coupling by Alfvén waves: Beyond current continuity, Advances in Space Research, 38(8), 713, 2006 [abstract] [download Lysak cospar 2006 paper.pdf]

Su, Y., S. T. Jones, R. E. Ergun, F. Bagenal, S. E. Parker, P. A. Delamere, and R. L. Lysak,, Io-Jupiter interaction: Alfvén wave propagation and ionospheric Alfvén resonator,, J. Geophys. Res., 111, A06211, doi: 10.1029/2005JA011252

rgun, R. E., Y.-J. Su, L. Andersson, F. Bagenal, P. A. Delamere, R. L. Lysak, and R. J. Strangeway, S bursts and the Jupiter ionospheric Alfvén resonator, J. Geophys. Res., 111, A06212, doi: 10.1029/2005JA011253 (2006)

Y. Song and R. L. Lysak, The displacement current and the generation of parallel electric fields, Phys. Rev. Lett., 96, 145002, 2006 [abstract] [download PRL displacement.pdf]

R. L. Lysak and Y. Song, Non-local interactions between electrons and Alfvén waves on auroral field lines, J. Geophys. Res., 110, A10S06, doi:10.1029/2004JA010803, 2005 [abstract]

Lysak, R. L., Magnetosphere-ionosphere coupling by Alfvén waves at mid-latitudes, J. Geophys. Res., 109, A07201, doi:10.1029/2004JA010454, 2004

Lysak, R. L., and Y. Song, Nonlocal kinetic theory of Alfvén waves on dipolar field lines, J. Geophys. Res., 108(A8), 1327, doi:10.1029/2003JA009859, 2003

Lysak, R. L., and Y. Song, Kinetic theory of the Alfvén wave acceleration of auroral electrons, J. Geophys. Res., 108(A4), 8005, doi:10.1029/2002JA009406, 2003.

Lysak, R. L., and Y. Song, Energetics of the ionospheric feedback interaction, J. Geophys. Res., 107(A8), 10.1029/2001JA000308, 2002.

Lysak, R. L., and Y. Song, A three-dimensional model of the propagation of Alfvén waves through the auroral ionosphere: First results, Adv. Space Research, 28, 813, 2001

Education

B.S., Michigan State University, 1975.
Ph.D., University of California, Berkeley, 1980.