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arXiv · 1106.2545

Confirmation of the VeLLO L1148-IRS: Star Formation at very low (Column) Density

J. Kauffmann·F. Bertoldi·T. L. Bourke·P. C. Myers·C. W. Lee·T. L. Huard
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Abstract

We report the detection of a compact (of order 5 arcsec; about 1800 AU projected size) CO outflow from L1148-IRS. This confirms that this Spitzer source is physically associated with the nearby (about 325 pc) L1148 dense core. Radiative transfer modeling suggests an internal luminosity of 0.08 to 0.13 L_sun. This validates L1148-IRS as a Very Low Luminosity Object (VeLLO; L < 0.1 L_sun). The L1148 dense core has unusually low densities and column densities for a star-forming core. It is difficult to understand how L1148-IRS might have formed under these conditions. Independent of the exact final mass of this VeLLO (which is likely < 0.24 M_sun), L1148-IRS and similar VeLLOs might hold some clues about the isolated formation of brown dwarfs.

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J. Kauffmann, F. Bertoldi, T. L. Bourke, P. C. Myers, C. W. Lee, T. L. Huard. 2011-06-13. Confirmation of the VeLLO L1148-IRS: Star Formation at very low (Column) Density. https://doi.org/10.1111/j.1365-2966.2011.19205.x

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