Fig. 6
From: Magnetic excitation of a granular gas as a bulk thermostat
Magnetic force–direction distributions. a Definitions of an angle difference (θres) between magnetic force–directions in cases A (without interaction) and B (with interaction) and a magnetic force angle in the fixed coordinate system in lab frame (θz, φx−y). The θres shows a deviation of the force–direction affected by the magnetic interactions between particles. An external magnetic field–direction at a particle position is the same as a direction of the magnetic force applied to the particle in case A. The θres is the difference between the external magnetic field–direction and the magnetic force–direction in case B. The θz is determined as a zenith angle from the z axis, and the φx−y is used as an azimuth angle from the x axis. b Distributions of the angle difference (θres), and c, d the magnetic force–directions in case A and case B (θz, φx−y). The magnetic forces applied at the first round of magnetic excitations are analyzed (at 0.01 s), and at the state, the particles move for inappreciable distances since the initial state in which the particles are distributed randomly
