HR: 0830h
AN: SP41A-07 [Abstracts]
TI: Investigation of Solar Coronal Heating Using a Time Dependent MHD Model with Full Conductivity Tensor
AU: * Kazeminezhad, F
EM: farzad@isr.us
AF: Institute for Scientific Research, Inc., 2500 Fairmont Avenue, Suite 734, Fairmont, WV 26555-2720
AU: Goodman, M L
EM: mgoodman@isr.us
AF: Institute for Scientific Research, Inc., 2500 Fairmont Avenue, Suite 734, Fairmont, WV 26555-2720
AB:
The transition region and lower corona is investigated using a newly developed time dependent MHD model that includes gravity and a self consistently computed conductivity tensor that depends on temperature, magnetic field, and density. The model is
tested by its ability to preserve FAL equilibrium profiles, and to generate MHD waves with dispersion relations similar to
those predicted by linear theory for the general types of MHD waves. The model is then used to examine solar atmospheric
heating by Pedersen and magnetic field aligned current dissipation. Numerical experiments are conducted in which MHD waves
are launched from either the transition region upward, or from the lower corona downward. Results from parametric studies of
the evolution of these waves as a function of wavelength and amplitude are presented. In particular, the heating rate due to
wave dissipation is compared with the FAL cooling rate, and with analytic results presented in M. Goodman [1,2]. %
. The relative importance of physical dissipation due to the conductivity tensor, and
numerical dissipation is estimated using Von Neumann stability analysis (VNSA) and numerical experiments with and without
physical dissipation. It is then attempted to extrapolate from the simulation data the waves which could potentially lead to
the correct heating rate, assumed to be the FAL net radiative loss rate. Realistic solar atmospheric data is used throughout
the numerical investigations. This work was supported in part by NSF grant ATM-0242820 to the Institute for Scientific
Research.
DE: 7500 SOLAR PHYSICS, ASTROPHYSICS, AND ASTRONOMY
DE: 7507 Chromosphere
DE: 7509 Corona
DE: 7546 Transition region
SC: Solar Physics Division - AAS [SP]
MN: 2005 Joint Assembly