Cosmic-Ray Acceleration from Turbulence in Molecular Clouds - Kölner UniversitätsPublikationsServer

Gaches, Brandt A. L., Walch, Stefanie ORCID: 0000-0001-6941-7638 and Lazarian, A. (2021). Cosmic-Ray Acceleration from Turbulence in Molecular Clouds. Astrophys. J. Lett., 917 (2). BRISTOL: IOP PUBLISHING LTD. ISSN 2041-8213

Full text not available from this repository.

DOI:10.3847/2041-8213/ac1b2f

Abstract

Low-energy cosmic rays, in particular protons with energies below 1 GeV, are significant drivers of the thermochemistry of molecular clouds. However, these cosmic rays are also greatly impacted by energy losses and magnetic field transport effects in molecular gas. Explaining cosmic-ray ionization rates of 10(-16) s(-1) or greater in dense gas requires either a high external cosmic-ray flux, or local sources of MeV-GeV cosmic-ray protons. We present a new local source of low-energy cosmic rays in molecular clouds: first-order Fermi acceleration of protons in regions undergoing turbulent reconnection in molecular clouds. We show from energetic-based arguments there is sufficient energy within the magnetohydrodynamic turbulent cascade to produce ionization rates compatible with inferred ionization rates in molecular clouds. As turbulent reconnection is a volume-filling process, the proposed mechanism can produce a near-homogeneous distribution of low-energy cosmic rays within molecular clouds.

Item Type:

Journal Article

Creators:

Creators	Email	ORCID	ORCID Put Code
Gaches, Brandt A. L.	UNSPECIFIED	UNSPECIFIED	UNSPECIFIED
Walch, Stefanie	UNSPECIFIED	orcid.org/0000-0001-6941-7638	UNSPECIFIED
Lazarian, A.	UNSPECIFIED	UNSPECIFIED	UNSPECIFIED