Finite thin disc models of four galaxies in the Ursa Major cluster: NGC3877, NGC3917, NGC3949 and NGC4010

TL;DR

This paper develops finite thin disc models for four Ursa Major cluster galaxies, accurately fitting their rotation curves and estimating their masses, providing a first approximation to realistic spiral galaxy models.

Contribution

It introduces a method using the Hunter approach to model galaxy rotation curves with thin disc assumptions, tailored to specific galaxies in the Ursa Major cluster.

Findings

Models fit observed rotation curves very accurately.

Estimated galaxy masses are around 10^10 solar masses.

Models serve as first approximations for realistic spiral galaxy modeling.

Abstract

Finite thin disc models of four galaxies in the Ursa Major cluster are presented. The models are obtained by means of the Hunter method and the particular solutions are choosen in such a way that the circular velocities are adjusted very accurately to the observed rotation curves of some specific spiral galaxies. We present particular models for the four galaxies NGC3877, NGC3917, NGC3949 and NGC4010 with data taken from the recent paper by Verheijen & Sancici (2001). By integrating the corresponding surface mass densities, we obtain the total mass M of these four galaxies, all of them being of the order of 10^10 solar masses. These obtained values for M may be taken as a quite accurately estimative of the mass upper bound of these galaxies, since in the model was considered that all their mass was concentrated at the galactic disc. The models can be consider as a first approximation to the obtaining of quite realistic models of spiral galaxies