Magnetic Ribbons: A Minimum Hypothesis Model for Filaments
  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 use our model to calculate a
synthetic observed relation between apparent width in projection versus
observed column density. The relationship is relatively flat, in rough
agreement with the observations, and unlike the simple expectation based on a
Jeans length argument.
