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arXiv · 1207.3843

The Envelope and Embedded Disk around the Class 0 Protostar L1157-mm: Dual-wavelength Interferometric Observations and Modeling

Hsin-Fang Chiang·Leslie W. Looney·John J. Tobin
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Abstract

We present dual-wavelength observations and modeling of the nearly edge-on Class 0 young stellar object L1157-mm. Using the Combined Array for Research in Millimeter-wave Astronomy, a nearly spherical structure is seen from the circumstellar envelope at the size scale of 10^2 to 10^3 AU in both 1 mm and 3 mm dust emission. Radiative transfer modeling is performed to compare data with theoretical envelope models, including a power-law envelope model and the Terebey-Shu-Cassen model. Bayesian inference is applied for parameter estimation and information criteria is used for model selection. The results prefer the power-law envelope model against the Terebey-Shu-Cassen model. In particular, for the power-law envelope model, a steep density profile with an index of ~2 is inferred. Moreover, the dust opacity spectral index (beta) is estimated to be ~0.9, implying that grain growth has started at L1157-mm. Also, the unresolved disk component is constrained to be < 40 AU in radius and < 4-25 M_Jup in mass. However, the estimate of the embedded disk component relies on the assumed envelope model.

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Hsin-Fang Chiang, Leslie W. Looney, John J. Tobin. 2012-07-16. The Envelope and Embedded Disk around the Class 0 Protostar L1157-mm: Dual-wavelength Interferometric Observations and Modeling. https://doi.org/10.1088/0004-637x/756/2/168

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