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arXiv · astro-ph/9904184

A Contracting, Turbulent, Starless Core in the Serpens Cluster

Jonathan P. Williams·Philip C. Myers
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Abstract

We present combined single-dish and interferometric CS(2--1) and N2H+(1--0) observations of a compact core in the NW region of the Serpens molecular cloud. The core is starless according to observations from optical to millimeter wavelengths and its lines have turbulent widths and ``infall asymmetry''. Line profile modeling indicates supersonic inward motions v_in>0.34 km/s over an extended region L>12000AU. The high infall speed and large extent exceeds the predictions of most thermal ambipolar diffusion models and points to a more dynamical process for core formation. A short (dynamic) timescale, ~1e5 yr=L/v_in, is also suggested by the low N2H+ abundance ~1e-10.

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Jonathan P. Williams, Philip C. Myers. 1999-04-14. A Contracting, Turbulent, Starless Core in the Serpens Cluster. https://doi.org/10.1086/312065

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