RT Journal Article T1 Formation of dust filaments in the diffuse envelopes of molecular clouds A1 Beitia Antero, Leire A1 Gómez de Castro, Ana I. A1 Vallejo Chavarino, Juan C. AB 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 non-negligible 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 µm) 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. PB IOP Publishing Ltd SN 0004-637X YR 2021 FD 2021-02 LK https://hdl.handle.net/20.500.14352/8001 UL https://hdl.handle.net/20.500.14352/8001 LA eng NO © 2021. The American Astronomical Society. We want to thank an anonymous referee for many helpful comments and suggestions that have helped to improve this manuscript. L. B.- A. acknowledges Universidad Complutense de Madrid and Banco Santander for the grant “Personal Investigador en Formación CT17/17-CT18/17”. This work has been partially funded by the Ministry of Economy and Competitiviness of Spain through grants MINECOESP2015-68908-R and MINECO-ESP2017-87813-R. L. B.-A. also wants to acknowledge I. Prada for useful discussion about how to build the dust maps and with the usage of the python image analysis packages. This research has made use of NASA’s Astrophysics Data System. NO Ministerio de Economía y Competitividad (MINECO) NO Universidad Complutense de Madrid /Banco de Santander DS Docta Complutense RD 30 abr 2024