A Hall MHD model to study energetic charged particle events produced during fluctuations in the interplanetary magnetic field intensity

2008 ◽  
Vol 56 (7) ◽  
pp. 913-916
Author(s):  
F.C. Huang ◽  
Z.W. Ma ◽  
Z.M. Sheng
Keyword(s):  
Magnetic Field ◽  
Charged Particle ◽  
Interplanetary Magnetic Field ◽  
Field Intensity ◽  
Magnetic Field Intensity ◽  
Mhd Model ◽  
Hall Mhd ◽  
Energetic Charged Particle

Cosmic ray modulations related to the interplanetary magnetic field intensity

1983 ◽  
Vol 88 (A4) ◽  
pp. 2973 ◽  
Author(s):  
S. P. Duggal ◽  
M. A. Pomerantz ◽  
R. K. Schaefer ◽  
C. H. Tsao
Keyword(s):  
Magnetic Field ◽  
Interplanetary Magnetic Field ◽  
Field Intensity ◽  
Magnetic Field Intensity ◽  
Cosmic Ray

Macro- and micro-structure of the interplanetary magnetic field

1968 ◽  
Vol 46 (10) ◽  
pp. S962-S965 ◽  
Author(s):  
Leonard F. Burlaga ◽  
Norman F. Ness
Keyword(s):  
Magnetic Field ◽  
Interplanetary Magnetic Field ◽  
Field Intensity ◽  
Magnetic Field Intensity ◽  
Ecliptic Plane ◽  
Micro Structure ◽  
Discontinuous Change ◽  
Radial Gradient ◽  
Directional Distributions ◽  
The Magnetic Field

A radial gradient of the interplanetary magnetic field between 0.81 and 1.0 AU has been observed in agreement with Parker's model. The average magnitude of the magnetic field component perpendicular to the ecliptic plane was zero during 1966.Discontinuities in the direction of the magnetic field were observed when viewing on a scale of one hour; directional distributions are presented which describe the topology of these discontinuities. It was found that sometimes a large, discontinuous change in the field direction was accompanied by a dip in the field intensity; the measured minimum magnetic field intensity agrees with the value calculated from the hypothesis that the dip was the result of magnetic field annihilation. At least two of these "D-sheets" appear to be transitional regions associated with tangential discontinuities.

scholarly journals Multi-point ground-based ULF magnetic field observations in Europe during seismic active periods in 2004 and 2005

2008 ◽  
Vol 8 (3) ◽  
pp. 501-507 ◽  
Author(s):  
G. Prattes ◽  
K. Schwingenschuh ◽  
H. U. Eichelberger ◽  
W. Magnes ◽  
M. Boudjada ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Field Intensity ◽  
Seismic Activity ◽  
Magnetic Field Intensity ◽  
Field Measurements ◽  
Fluxgate Magnetometer ◽  
Vertical Magnetic Field ◽  
Earthquake Epicenter ◽  
Electromagnetic Noise ◽  
Horizontal Magnetic Field

Abstract. We present the results of ground-based Ultra Low Frequency (ULF) magnetic field measurements observed from June to August 2004 during the Bovec earthquake on 12 July 2004. Further we give information about the seismic activity in the local observatory region for an extended time span 2004 and 2005. ULF magnetic field data are provided by the South European Geomagnetic Array (SEGMA) where the experience and heritage from the CHInese MAGnetometer (CHIMAG) fluxgate magnetometer comes to application. The intensities of the horizontal H and vertical Z magnetic field and the polarization ratio R of the vertical and horizontal magnetic field intensity are analyzed taking into consideration three SEGMA observatories located at different close distances and directions from the earthquake epicenter. We observed a significant increase of high polarization ratios during strong seismic activity at the observatory nearest to the Bovec earthquake epicenter. Apart from indirect ionospheric effects electromagnetic noise could be emitted in the lithosphere due to tectonic effects in the earthquake focus region causing anomalies of the vertical magnetic field intensity. Assuming that the measured vertical magnetic field intensities are of lithospheric origin, we roughly estimate the amplitude of electromagnetic noise in the Earths crust considering an average electrical conductivity of <σ>=10−3 S/m and a certain distance of the observatory to the earthquake epicenter.

Numerical Investigations on Rotatry Micropolar Fluid in Hydromagnetics Permeated with Suspended Particles Saturating Porous Medium

2021 ◽  
pp. 57-69
Author(s):  
Pushap Lata Sharma ◽  
Sumit Gupta
Keyword(s):  
Magnetic Field ◽  
Porous Medium ◽  
Field Intensity ◽  
Magnetic Field Intensity ◽  
Suspended Particles ◽  
Rotation Parameter ◽  
Wave Number ◽  
Stationary Convection ◽  
Micropolar Fluids ◽  
Medium Permeability

This paper deals with the convection of micropolar fluids heated and soluted from below in the presence of suspended particles (fine dust) and uniform vertical rotation and uniform vertical magnetic field in a porous medium. Using the Boussinesq approximation, the linearized stability theory and normal mode analysis, the exact solutions are obtained for the case of two free boundaries. It is found that the presence of the suspended particles number density, the rotation parameter, stable solute, magnetic field intensity and medium permeability bring oscillatory modes which were non–existent in their absence. It is found that the presence of coupling between thermal and micropolar effects, rotation parameter, solute parameter and suspended particles may introduce overstability in the system. Graphs have been plotted by giving numerical values to the parameters accounting for rotation parameter , magnetic field solute parameter, the dynamic microrotation viscosity and coefficient of angular viscosity to depict the stability characteristics, for both the cases of stationary convection and overstability. It is found that Rayleigh number for the case of overstability and stationary convection increases with increase in rotation parameter, as well as with magnetic field intensity, solute parameter and decreases with increase in micropolar coefficients and medium permeability, for a fixed wave number, implying thereby the stabilizing effect of rotation parameter, magnetic field intensity ,solute parameter and destabilizing effect of micropolar coefficients and medium permeability on the thermosolutal convection of micropolar fluids.

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