V-645 CYGNI - A DECELERATING MOLECULAR OUTFLOW

DOI: 
Publication date: 
01/04/1991
Main author: 
VERDESMONTENEGRO, L
IAA authors: 
VERDESMONTENEGRO, L
Authors: 
VERDESMONTENEGRO, L; GOMEZ, JF; TORRELLES, JM; ANGLADA, G; ESTALELLA, R; LOPEZ, R
Journal: 
ASTRONOMY & ASTROPHYSICS
Publication type: 
Article
Volume: 
244
Pages: 
84-94
Number: 
Abstract: 
V645 Cygni (AFGL 2789) is a young stellar object associated with a bipolar molecular outflow with a modest degree of collimation. In this paper we present IRAM 30-m observations of the CO(J = 2 --> 1), (CO)-C-13(J = 1 --> 0) and C18O(J = 1 --> 0) rotational transition lines toward this region. At relatively low velocities the molecular outflow presents a bipolarity in the north-south direction, with the red and blueshifted CO lobes separated by approximately 20'. This angular separation decreases as the velocity increases. At higher velocities the outflow appears isotropic. The physical parameters obtained for the V645 Cyg molecular outflow (i.e., mass, momentum rate and mechanical luminosity) are much lower than the parameters derived for other outflows with exciting sources of similar luminosities (L* congruent-to 10(4) L.). In particular, this result makes it possible that radiation pressure may be responsible for generating the stellar wind associated with V645 Cyg. All these results lead us to suggest that the outflowing molecular gas could be decelerating as it moves away from the central V645 Cyg position. The integrated C18O emission presents an elongated structure with a velocity gradient of approximately 0.7 km s-1 pc-1 in the east-west direction. The mass derived is sufficient to bind these motions.
Database: 
WOK
Keywords: 
INTERSTELLAR MEDIUM, MOLECULES; STARS, FORMATION, MASS LOSS