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

Abstract

We present sub-arcsecond resolution imaging of the $\lambda$ = 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 $\lambda$ = 2 cm and $\lambda$ = 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.