Individual Elemental Abundances in Elliptical Galaxies

TL;DR

This paper develops new spectral indices to identify individual element abundances in elliptical galaxies, investigates Balmer emission detection, and analyzes stellar population effects on spectra, providing insights into galaxy composition and evolution.

Contribution

It introduces novel spectral indices targeting individual elements, enabling detailed chemical analysis of elliptical galaxies using synthetic spectra and observational data.

Findings

New indices can detect specific element abundances in galaxy spectra.

Old metal-poor populations explain UV-optical spectral discrepancies.

Gradient analysis reveals element distribution variations in elliptical galaxies.

Abstract

Using synthetic spectra to gauge the observational consequences of altering the abundance of individual elements, I determine the observability of new Lick IDS style indices designed to target individual elements. Then using these new indices and single stellar population models, I investigate a new method to determine Balmer series emission in a Sloan Digital Sky Surveys grand average of quiescent galaxies. I also investigate the effects of an old metal-poor stellar population on the near ultra violet spectrum through the use of these new indices and find that the presence of a small old metal-poor population accounts for discrepancies observed between index trends in the near UV and optical spectral regimes. Index trends for 74 indices and three data sets are presented and discussed. Finally, I determine the near nuclear line-strength gradients of 18 red sequence elliptical Virgo cluster galaxies for 74 indices.