Measurements of dipole moments and a Q-patch model of collisionally charged grains

Abstract

Identical glass spheres of 434 ± 17 μ m diameter are charged in collisions among each other. At slow speed some form dimers under microgravity and oscillate within the electrical field of a capacitor. The dipole moments deduced from these oscillations are large. They cannot be explained by the net charges measured for each grain (up to ±3 × 10 ^5 e ) and show no significant dependence on the net charge in the given range. This requires a highly non-homogeneous charge distribution on the grain surface. We simulate heterogeneous charging with a Q-patch charging model in agreement to the experimental data.

Keywords

• electrical dipole moment
• static charge
• triboelectric effect
• experimental measurements
• computer simulation
• Q-patch model