2020/08/31 by Leire Beitia-Antero, L. Beitia-Antero, Ana I. Gómez de Castro +3
Earth and Planetary Sciences · Physics and Astronomy · #Astrophysics #Astrophysics and Star Formation Studies #Atmospheric Ozone and Climate #Chemical physics #Cosmic dust #Galaxy #Interstellar medium #Ion #Ionization #Magnetic field #Molecular cloud #Physics #Population #Star formation #Stars #Stellar, planetary, and galactic studies #astro-ph.GA
paper · pdf · doi:10.3847/1538-4357/abcda1
16 pages, 14 figures, accepted for publication in ApJ
arxiv created 2020/11/24 · openalex publication_date 2021/02/01 · arxiv updated 2021/02/24 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/06
Abstract The path to understanding star formation processes begins with the study of the formation of molecular clouds. The outskirts of these clouds are characterized by low column densities that allow the penetration of ultraviolet radiation, resulting in a nonnegligible ionization fraction and the charging of the small dust grains that are mixed with the gas; this diffuse phase is then coupled to the ambient magnetic field. Despite the general assumption that dust and gas are tightly correlated, several observational and theoretical studies have reported variations in the dust-to-gas ratio toward diffuse and cold clouds. In this work, we present the implementation of a new charged particles module for analyzing the dust dynamics in molecular cloud envelopes. We study the evolution of a single population of small charged grains (0.05 μ m) in the turbulent, magnetized molecular cloud envelope using this module. We show that variations in the dust-to-gas ratio arise due to the coupling of the grains with the magnetic field, forming elongated dust structures decoupled from the gas. This emphasizes the importance of considering the dynamics of charged dust when simulating the different phases of the interstellar medium, especially for star formation studies.