A MAGNETIC RIBBON MODEL for STAR-FORMING FILAMENTS

Authors

Sayantan Auddy, The University of Western Ontario
Shantanu Basu, The University of Western OntarioFollow
Takahiro Kudoh, Nagasaki University

Document Type

Article

Publication Date

11-1-2016

Journal

Astrophysical Journal

Volume

831

Issue

1

URL with Digital Object Identifier

10.3847/0004-637X/831/1/46

Abstract

We develop a magnetic ribbon model for molecular cloud filaments. These result from turbulent compression in a molecular cloud in which the background magnetic field sets a preferred direction. We argue that this is a natural model for filaments and is based on the interplay between turbulence, strong magnetic fields, and gravitationally driven ambipolar diffusion, rather than pure gravity and thermal pressure. An analytic model for the formation of magnetic ribbons that is based on numerical simulations is used to derive a lateral width of a magnetic ribbon. This differs from the thickness along the magnetic field direction, which is essentially the Jeans scale. We use our model to calculate a synthetic observed relation between apparent width in projection versus observed column density. The relationship is relatively flat, similar to observations, and unlike the simple expectation based on a Jeans length argument.