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High Resolution $λ$ = 2.7 mm Observations of L1551 IRS5: A Protobinary System?

Leslie W. Looney·Lee G. Mundy·W. J. Welch
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Abstract

We present sub-arcsecond resolution imaging of the $λ$ = 2.7 mm continuum emission from the young, embedded system L1551 IRS5 using the nine-element, high-resolution configuration of the BIMA array. The observed emission arises from two compact sources separated by $0\farcs$35, coinciding with the two sources seen at $λ$ = 2 cm and $λ$ = 1.3 cm. When the high resolution data is combined with data from two compact configurations, L1551 IRS5 is argued to consist of a protobinary system separated by $\sim$50 AU with individual circumstellar disks, a circumbinary structure, and a large-scale envelope. The characteristic masses of the components are: 0.024 M$_{\sun}$ for the northern circumstellar disk, 0.009 M$_{\sun}$ for the southern circumstellar disk, 0.04 M$_{\sun}$ for the circumbinary material, and 0.28 M$_{\sun}$ for the envelope.

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Leslie W. Looney, Lee G. Mundy, W. J. Welch. 1997-05-27. High Resolution $λ$ = 2.7 mm Observations of L1551 IRS5: A Protobinary System?. https://doi.org/10.1063/1.52777

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