Proper motions of L1551 IRS 5 binary system using 7 mm VLA observations

Abstract

We analyzed high angular resolution observations of the Very Large Array archive at a wavelength of 7 mm of the L1551 IRS 5 binary system. Six sets of observations,five with the A configuration and one with the B configuration, were used, covering a time span of about 15 years. With these multi-epoch data, we estimated the absolute and relative proper motions of the binary system, which are about 25.1 mas/yr (~ 16.7 km/s considering a distance of 140 pc) and 4.2 mas/yr, respectively. Finally, based on the relative proper motion, we estimated a total mass of the L1551 IRS 5 binary system of 1.7 Msun and an orbital period of 246 years.