Abstract
Observations of the CO J=1–0 line are commonly used as a tracer for molecular material in clouds. The ratio of the H2 column density to the integrated intensity of this line, X, is often taken to be constant, despite theoretical and observational uncertainty. We have tried to identify how this ratio depends on cloud parameters, testing a simple theoretical argument suggesting its invariance with respect to density. The apparent constancy can be understood if clouds are clumpy on scales of Av ≈ 1–2 mag.
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© 1994 Springer Science+Business Media Dordrecht
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Taylor, S.D., Williams, D.A., Hartquist, T.W. (1994). Modelling The Constancy of X . In: Dyson, J.E., Carling, E.B. (eds) Kinematics and Dynamics of Diffuse Astrophysical Media. Springer, Dordrecht. https://doi.org/10.1007/978-94-011-0926-0_26
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DOI: https://doi.org/10.1007/978-94-011-0926-0_26
Publisher Name: Springer, Dordrecht
Print ISBN: 978-94-010-4399-1
Online ISBN: 978-94-011-0926-0
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