Using Gas Kinematics To Constrain 3D Models of Disks: IC 2531

TL;DR

This study uses deep spectroscopic data of galaxy IC 2531 to analyze gas kinematics across extensive radial and vertical ranges, providing constraints for 3D disk models and insights into disk structure and flaring.

Contribution

It introduces a method to constrain 3D galaxy disk models using deep spectroscopic data spanning large vertical and radial extents.

Findings

Evidence of disk flaring in ionized gas

Constraints on 3D disk shape from emission-line profiles

Quantitative line shape analysis for model-data comparison

Abstract

We use deep, longslit spectra of the nearby edge on galaxy IC 2531 to obtain gas kinematics out to 5 radial scale-lengths (40 kpc) and 4 vertical scale-heights (1.7 kpc). The large vertical range spanned by our data offers unique leverage to constrain three-dimensional models. The shape of the observed emission-line profiles offer insights to line-of-sight density distributions in the disk, and we discuss the possibility that we are seeing disk-flaring in the ionized gas. Finally, we begin to quantify measurements of line shape to allow model galaxies to be compared to data across all radii and heights simultaneously.