Dynamical modelling of the elliptical galaxy NGC 2974

TL;DR

This paper models the elliptical galaxy NGC 2974 using an oblate Jaffe model, fitting observational data to estimate its mass and structure while assuming dark matter effects are minimal in the central region.

Contribution

It introduces a detailed dynamical model for NGC 2974 based on the oblate Jaffe profile, fitting observational data to derive galaxy parameters and mass estimates.

Findings

Good fit of the oblate Jaffe model to observed ellipticity and Gauss-Hermite parameters.

Estimated total luminous mass of NGC 2974 consistent with observations.

Model suggests dark matter influence is negligible within the central region.

Abstract

In this paper we analyse the relations between a previously described oblate Jaffe model for an ellipsoidal galaxy and the observed quantities for NGC 2974, and obtain the length and velocity scales for a relevant elliptical galaxy model. We then derive the finite total mass of the model from these scales, and finally find a good fit of an isotropic oblate Jaffe model by using the Gauss-Hermite fit parameters and the observed ellipticity of the galaxy NGC 2974. The model is also used to predict the total luminous mass of NGC 2974, assuming that the influence of dark matter in this galaxy on the image, ellipticity and Gauss-Hermite fit parameters of this galaxy is negligible within the central region, of radius $0.5R_{\rm e}.$