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A High Resolution Study of the Slowly Contracting, Starless Core L1544

Jonathan P. Williams·Philip C. Myers·David J. Wilner·James Di Francesco
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Abstract

We present interferometric observations of N2H+(1--0) in the starless, dense core L1544 in Taurus. Red-shifted self-absorption, indicative of inward motions, is found toward the center of an elongated core. The data are fit by a non-spherical model consisting of two isothermal, rotating, centrally condensed layers. Through a hybrid global-individual fit to the spectra, we map the variation of infall speed at scales ~1400AU and find values ~0.08 km/s around the core center. The inward motions are small in comparison to thermal, rotational, and gravitational speeds but are large enough to suggest that L1544 is very close to forming a star.

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Jonathan P. Williams, Philip C. Myers, David J. Wilner, James Di Francesco. 1999-01-06. A High Resolution Study of the Slowly Contracting, Starless Core L1544. https://doi.org/10.1086/311895

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