$^{12}$CO emission from the Red Rectangle

TL;DR

This study uses high-quality ALMA observations of CO emissions from the Red Rectangle to analyze its gas morphology and kinematics, revealing polar outflows, a rotating torus, and temperature variations.

Contribution

It presents simple models for the gas structures and compares different CO transitions to infer temperature and density distributions.

Findings

Detection of polar conical outflows

Identification of a broad rotating and expanding equatorial torus

Evidence for temperature enhancement in polar outflows

Abstract

Observations of an unprecedented quality made by ALMA on the Red Rectangle of CO(3-2) and CO(6-5) emissions are analysed jointly with the aim of obtaining as simple as possible a description of the gas morphology and kinematics. Evidence is found for polar conical outflows and for a broad equatorial torus in rotation and expansion. Simple models of both are proposed. Comparing CO(6-5) and CO(3-2) emissions provides evidence for a strong temperature enhancement over the polar outflows. Continuum emission (dust) is seen to be enhanced in the equatorial region. Observed asymmetries are briefly discussed.