Solar wind-magnetosphere energy input functions

Conference · Tue Jan 01 04:00:00 EST 1985

DOI:https://doi.org/10.1007/978-94-009-4722-1_7· OSTI ID:5749040

Bargatze, L F; McPherron, R L; Baker, D N

A new formula for the solar wind-magnetosphere energy input parameter, P/sub i/, is sought by applying the constraints imposed by dimensional analysis. Applying these constraints yields a general equation for P/sub i/ which is equal to rho V/sup 3/l/sub CF//sup 2/F(M/sub A/,theta) where, rho V/sup 3/ is the solar wind kinetic energy density and l/sub CF//sup 2/ is the scale size of the magnetosphere's effective energy ''collection'' region. The function F which depends on M/sub A/, the Alfven Mach number, and on theta, the interplanetary magnetic field clock angle is included in the general equation for P/sub i/ in order to model the magnetohydrodynamic processes which are responsible for solar wind-magnetosphere energy transfer. By assuming the form of the function F, it is possible to further constrain the formula for P/sub i/. This is accomplished by using solar wind data, geomagnetic activity indices, and simple statistical methods. It is found that P/sub i/ is proportional to (rho V/sup 2/)/sup 1/6/VBG(theta) where, rho V/sup 2/ is the solar wind dynamic pressure and VBG(theta) is a rectified version of the solar wind motional electric field. Furthermore, it is found that G(theta), the gating function which modulates the energy input to the magnetosphere, is well represented by a ''leaky'' rectifier function such as sin/sup 4/(theta/2). This function allows for enhanced energy input when the interplanetary magnetic field is oriented southward. This function also allows for some energy input when the interplanetary magnetic field is oriented northward. 9 refs., 4 figs.

• Research Organization: California Univ., Los Angeles (USA). Dept. of Earth and Space Sciences; California Univ., Los Angeles (USA). Inst. of Geophysics and Planetary Physics; Los Alamos National Lab., NM (USA)
• DOE Contract Number: W-7405-ENG-36
• OSTI ID: 5749040
• Report Number(s): LA-UR-85-1303; CONF-850277-3; ON: DE85010761
• Country of Publication: United States
• Language: English

Related Subjects

640203* -- Atmospheric Physics-- Magnetospheric Phenomena-- (-1987)
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
DYNAMICS
EARTH ATMOSPHERE
ENERGY DENSITY
ENERGY TRANSFER
FLUID MECHANICS
HYDRODYNAMICS
INTERPLANETARY MAGNETIC FIELDS
MAGNETIC FIELDS
MAGNETOHYDRODYNAMICS
MAGNETOSPHERE
MATHEMATICAL MODELS
MECHANICS
SOLAR ACTIVITY
SOLAR WIND
STATISTICAL MODELS