An H$\alpha$ kinematic survey of the $Herschel$ Reference Survey -- I. Fabry-Perot observations with the 1.93m telescope at OHP

TL;DR

This study provides high-resolution 2D Hα kinematic maps for 152 nearby star-forming galaxies from the Herschel Reference Survey, enabling detailed analysis of their rotation curves and baryonic-dynamical mass relations.

Contribution

It introduces improved data reduction and adaptive binning techniques for Fabry-Perot spectroscopic data, and presents the first detailed study of the baryonic and dynamical main sequence in local galaxies.

Findings

High-resolution Hα velocity fields enable precise rotation curve measurements.

Good agreement between Hα and HI rotational velocities validates the method.

Established the baryonic and dynamical main sequence for local galaxies.

Abstract

We present new 2D high resolution Fabry-Perot spectroscopic observations of 152 star-forming galaxies which are part of the $Herschel$ Reference Survey (HRS), a complete $K$-band selected, volume-limited sample of nearby galaxies, spanning a wide range in stellar mass and morphological type. Using improved data reduction techniques that provide adaptive binning based on Voronoi tessellation, using large field-of-view observations, we derive high spectral resolution (R$>$10,000) H$\alpha$ datacubes from which we compute H$\alpha$ maps and radial 2D velocity fields that are based on several thousand independent measurements. A robust method based on such fields allows us to accurately compute rotation curves and kinematical parameters, for which uncertainties are calculated using a method based on the power spectrum of the residual velocity fields. We check the consistency of the rotation curves by comparing our maximum rotational velocities to those derived from HI data, and computing the $i$-band, NIR, stellar and baryonic Tully-Fisher relations. We use this set of kinematical data combined to those available at other frequencies to study for the first time the relation between the dynamical and the total baryonic mass (stars, atomic and molecular gas, metals and dust), and derive the baryonic and dynamical main sequence on a representative sample of the local universe.