Runaway growth of fractal dust grains

TL;DR

This paper explores the growth and properties of fractal dust grains with large surface areas, focusing on the implications of constant volume-area ratios for dust formation in AGB stars.

Contribution

It introduces the mathematical analysis of fractal dust grains with constant volume-area ratios and discusses their potential impact on understanding dust and wind formation in AGB stars.

Findings

Fractal grains have large surface areas enhancing condensation.

Constant volume-area ratio grains model rough or aggregated surfaces.

Implications for dust formation processes in AGB stars.

Abstract

Fractal grains have large surface area, which leads to more efficient condensation. The special limit case where the volume-area ratio is constant (corresponding to, e.g., a very rough grain surface or non-compacts aggregates) is particularly interesting, as well as convenient, from a mathematical point of view. If dust grains from AGB stars have `rough surfaces', it may have important implications for our understanding of dust and wind formation in AGB stars.