Morpho-Kinematic Properties of the 21-Micron Source IRAS 07134+1005

TL;DR

This study uses interferometric observations and modeling to characterize the shape and expansion of the molecular envelope around IRAS 07134+1005, revealing a thick expanding torus and insights into its evolutionary stage.

Contribution

It provides the first detailed morpho-kinematic model of the molecular envelope of IRAS 07134+1005 using SMA data and Shape software, linking structure to stellar evolution.

Findings

The envelope is a geometrically thick expanding torus.

Inner and outer radii of the torus are 1.2" and 3.0".

Expansion velocity of the torus is 8 km/s.

Abstract

We report the results of a Submillimeter Array (SMA) interferometric observation of 21-micron source IRAS 07134+1005 in the CO J=3-2 line. In order to determine the morpho-kinematic properties of the molecular envelope of the object, we constructed a model using the Shape software to model the observed CO map. We find that the molecular gas component of the envelopes can be interpreted as a geometrically thick expanding torus with an expanding velocity of 8 km/s. The inner and outer radii of the torus determined by fitting Shape models are 1.2" and 3.0", respectively. The inner radius is consistent with the previous values determined by radiative transfer modeling of the spectral energy distribution and mid-infrared imaging of the dust component. The radii and expansion velocity of the torus suggest that the central star has left the asymptotic giant branch about 1140-1710 years ago, and that the duration of the equatorial enhanced mass loss is about 2560-3130 years. From the absence of an observed jet, we suggest that the formation of a bipolar outflow may lack behind in time from the creation of the equatorial torus.