The Observability of Abundance Ratio Effects in Elliptical Galaxies

Using synthetic spectra we construct a simple model of an elliptical galaxy, with a velocity dispersion σ = 200 km s^-1. Absorption feature indices are defined for C, N, O, Na, Mg, Al, Si, S, K, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Sr, Ba, and Eu as a first step in determining the abundances of these elements in stellar populations, such as elliptical galaxies, for which integrated light spectra are available. Then using these indices and assuming a photon error such that S/N = 100 around 5000 Å , the feasibility of measuring individual elements in real galaxies is assessed. Of the elements studied only S, K, Cu, Zn, and Eu appear to be difficult to determine; the rest appear to be at least feasible.