The SFH of the LMC: The CMD approach vs. integrated colors and spectra

Abstract

We present results of a study aiming at shedding light on the specific advantages and limitations of methods to derive star formation histories (SFH) in galaxies using resolved stellar populations and using integrated light, respectively. For this purpose, we analyse the integrated-light spectrum of a field in the LMC bar, for which highly resolved HST images are available as well. To be compared with the SFH derived from the color magnitude diagram (CMD) of this field (Smecker-Hane et al. 02), we have performed a set of simulations of galaxies with systematically varying SFHs, but constant metallicity (Z=0.008). We investigate to which extent different SF scenarios can be discriminated on the basis of their photometric and spectral properties, respectively, and determine in how far the detailed SFH obtained by the CMD approach can be reproduced by results based upon integrated properties. Comparing both methods for this nearby field we want to learn about the specific character of both methods and understand to what precision SFHs can be determined for distant galaxies only observable in integrated light. All simulations are performed using our evolutionary synthesis code GALEV.