The effects of velocity shear on the resonance absorption of MHD surface waves: Cold plasma

Journal Article · Thu Aug 01 04:00:00 EDT 1991 · Journal of Geophysical Research; (United States)

DOI:https://doi.org/10.1029/91JA01407· OSTI ID:5155744

Yang, Guang; Hollweg, J V ^[1]

---

1. Univ. of New Hampshire, Durham (United States)

Magnetohydrodymnamic (MHD) surface waves may decay via a process called resonance absorption, which is a candidate for solar coronal heating. Recently, Hollweg, Yang, Cadez and Gakovic studied the effects of velocity shear on the rate of resonance absorption of incompressible MHD surface waves. The authors extend the theory to a compressible but cold plasma, which is the case more applicable to the solar corona. They find that the rate of resonance absorption can be either increased or decreased significantly by velocity shear. They also find that there can exist resonances which lead to instability of the surface mode at values of the velocity shear below the Kelvin-Helmholtz threshold. However, the resonance instability usually occurs when the density ratio across the surface is less than about 0.1. The resonant instability may therefore not be important in the solar corona, though resonance absorption remains an atractive possibility for coronal heating.

• OSTI ID: 5155744
• Journal Information: Journal of Geophysical Research; (United States), Journal Name: Journal of Geophysical Research; (United States) Vol. 96:A8; ISSN 0148-0227; ISSN JGREA
• Country of Publication: United States
• Language: English

Related Subjects

640104* -- Astrophysics & Cosmology-- Solar Phenomena
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ABSORPTION
ATMOSPHERES
COLD PLASMA
DATA ANALYSIS
FLUID FLOW
HEATING
HELMHOLTZ INSTABILITY
HYDROMAGNETIC WAVES
INCOMPRESSIBLE FLOW
INSTABILITY
PLASMA
PLASMA HEATING
PLASMA INSTABILITY
PLASMA MACROINSTABILITIES
RESONANCE ABSORPTION
SHEAR
SOLAR ATMOSPHERE
SOLAR CORONA
STELLAR ATMOSPHERES
STELLAR CORONAE
VELOCITY