Proper Motions of the Jets in the Region of HH 30 and HL/XZ Tau: Evidence for a Binary Exciting Source of the HH 30 Jet

• Published in: The Astronomical journal 2007-06, Vol.133 (6), p.2799-2814
• Main Authors: Anglada, Guillem, López, Rosario, Estalella, Robert, Masegosa, Josefa, Riera, Angels, Raga, Alejandro C
• Format: Article
• Language: English
• ISSN: 1538-3881; 0004-6256; 1538-3881
• DOI: 10.1086/517493

We present [S II] images of the HH 30 and HL/XZ Tau region obtained at two epochs, as well as long-slit optical spectroscopy of the HH 30 jet. We measured proper motions of ~100-300 km s-1 for the HH 30 jet and counterjet and of ~120 km s-1 for the HL Tau jet. Inclination angles with respect to the plane of the sky are 0°-40° for the HH 30 jet and 60° for the HL Tau jet. Comparison with previous observations suggests that most of the jet knots consist of persistent structures. Also, we corroborate that the HH 30-N knots correspond to the head of the HH 30 jet. The overall HH 30 jet structure can be well described by a wiggling ballistic jet, arising either from orbital motion of the jet source around a primary or from precession of the jet axis because of the tidal effects of a companion. In the first scenario, the orbital period would be 53 yr and the total mass 0.25-2 M. In the precession scenario, the mass of the jet source would be ~0.1-1 M, the orbital period