Baryonic Distributions in Galaxy Dark Matter Haloes I: New Observations of Neutral and Ionized Gas Kinematics

TL;DR

This paper combines new and archival HI and ionized gas observations to analyze the baryonic and dark matter distributions in sixteen galaxies, providing detailed rotation curves and mass decompositions.

Contribution

It introduces comprehensive rotation curve analyses using multi-wavelength data and explores the impact of different assumptions on mass distribution in galaxy halos.

Findings

Rotation curves derived from VLA and WSRT data.

Ionized gas kinematics constrained by WIYN IFU observations.

Mass decomposition varies with stellar M/L and disc assumptions.

Abstract

We present a combination of new and archival neutral hydrogen (HI) observations and new ionized gas spectroscopic observations for sixteen galaxies in the statistically representative EDGES kinematic sample. HI rotation curves are derived from new and archival radio synthesis observations from the Very Large Array (VLA) as well as processed data products from the Westerbork Radio Synthesis Telescope (WSRT). The HI rotation curves are supplemented with optical spectroscopic integral field unit (IFU) observations using SparsePak on the WIYN 3.5 m telescope to constrain the central ionized gas kinematics in twelve galaxies. The full rotation curves of each galaxy are decomposed into baryonic and dark matter halo components using 3.6$\mu$m images from the Spitzer Space Telescope for the stellar content, the neutral hydrogen data for the atomic gas component, and, when available, CO data from the literature for the molecular gas component. Differences in the inferred distribution of mass are illustrated under fixed stellar mass-to-light ratio (M/L) and maximum disc/bulge assumptions in the rotation curve decomposition.