Dust in the Edgeworth-Kuiper belt zone

TL;DR

This paper models the orbital evolution of dust particles in the Edgeworth-Kuiper belt, highlighting the significant impact of variable solar wind and radiation forces on dust lifetime and distribution.

Contribution

It introduces a comprehensive model including solar wind variability and electromagnetic radiation effects, revealing their influence on dust particle lifetimes in the belt.

Findings

Variable solar wind increases dust lifetime by over 30 times.

Electromagnetic radiation pressure significantly affects dust dynamics.

Dust distribution insights apply to other stellar systems.

Abstract

Orbital evolution of spherical interplanetary dust particles in the Edgeworth-Kuiper belt zone is treated for semimajor axes 30-50 AU. Besides solar gravity, also solar electromagnetic and corpuscular radiation, and, fast interstellar gas flow are important forces influencing motion of the particles. The solar electromagnetic radiation is represented by the Poynting-Robertson effect and the solar corpuscular radiation corresponds to the solar wind. Time-variability of the non-radial solar wind can significantly increase dust lifetime in the zone. The average time for the particle stay in the zone is more than 30-times greater than the conventional case of constant (time independent) radial solar wind offers, for the particles of tens micrometers in size. This holds for the most realistic material properties of the particles: $\bar{Q}'_{pr} =$ 1, where $\bar{Q}'_{pr}$ is the dimensionless efficiency factor for electromagnetic radiation pressure. If $\bar{Q}'_{pr} =$ 1/2, then the average time of the particle stay in the zone is only 4-times the conventional value. The approach used in the paper illustrates the relevance of the solar wind action in comparison with the Poynting-Robertson effect. The results have an important consequence for our understanding of the structure of dust distribution in the Edgeworth-Kuiper belt zone, and, also, of dust belts in other stellar systems.