The Ursa Major Cluster of Galaxies. IV ; HI synthesis observations

TL;DR

This paper presents detailed HI synthesis imaging data for 43 spiral galaxies in the Ursa Major cluster, providing kinematic information crucial for studying galaxy dynamics, dark matter, and the Tully-Fisher relation.

Contribution

It offers a comprehensive dataset of HI observations and kinematic analysis for a well-defined galaxy sample, enabling advanced studies of galaxy properties and dark matter halos.

Findings

Relation between HI linewidth and rotational velocities analyzed

Comparison of optical and HI inclination angles conducted

Dataset suitable for Tully-Fisher and dark matter studies

Abstract

In this data paper we present the results of an extensive 21cm-line synthesis imaging survey of 43 spiral galaxies in the nearby Ursa Major cluster using the Westerbork Synthesis Radio Telescope. Detailed kinematic information in the form of position-velocity diagrams and rotation curves is presented in an atlas together with HI channel maps, 21cm continuum maps, global HI profiles, radial HI surface density profiles, integrated HI column density maps, and HI velocity fields. The relation between the corrected global HI linewidth and the rotational velocities Vmax and Vflat as derived from the rotation curves is investigated. Inclination angles obtained from the optical axis ratios are compared to those derived from the inclined HI disks and the HI velocity fields. The galaxies were not selected on the basis of their HI content but solely on the basis of their cluster membership and inclination which should be suitable for a kinematic analysis. The observed galaxies provide a well-defined, volume limited and equidistant sample, useful to investigate in detail the statistical properties of the Tully-Fisher relation and the dark matter halos around them.