The mass profile of NGC 3377 from a Bayesian approach

TL;DR

This study uses a Bayesian spherical Jeans analysis with observational and simulated priors to determine the mass profile of NGC 3377, favoring a satellite halo with an intermediate mass.

Contribution

It introduces a Bayesian approach combining multiple data sources and priors to analyze the galaxy's mass profile, considering various halo models and anisotropies.

Findings

Virial mass around 3.6 x 10^{11} solar masses

Satellite halo is preferred over central halo

Intermediate mass halo identified

Abstract

The mass profile for the moderately bright elliptical NGC 3377 is studied through an spherical Jeans analysis, combined with a Bayesian approach. The prior distributions are generated from dark matter simulations and observational constraints. The observational data set consist of Gemini/GMOS long-slit observations aligned with the major and minor axes of the galaxy, and are supplemented with data from the literature for the diffuse stellar component, globular clusters and planetary nebulae. Although the galaxy is assumed to alternatively reside in central and satellite haloes, the comparison with literature results prefer the latter option. Several options of constant anisotropy are considered, as well as both NFW and Einasto mass profiles. The analysis points to an intermediate mass halo, presenting a virial mass around $(3.6\pm0.6)\times 10^{11}\,{\rm M_{\odot}}$.