From the IMF to the S-Process in Early-Type Galaxies

Our understanding of the stellar populations of unresolved galaxies is
fundamentally limited by our lack of knowledge of the stellar initial
mass function (IMF), and its variation with environment and epoch.  In
this talk I will present a technique that provides direct measurements
of the low-mass IMF (~0.1-1 Msun) in unresolved stellar systems.  When
this technique is applied to high-quality optical-NIR spectra of
nearby early-type galaxies, evidence is found for an IMF that is
substantially more "bottom-heavy" than the Galactic IMF.  I will also
discuss ongoing work aimed at measuring elemental abundances
(including C, N, O, Na, Mg, Ca, Ti, Cr, Mn, Fe, Sr, and Ba) of these
galaxies, with the goal of constraining their formation histories.