IAC-pop: Finding the Star Formation History of Resolved Galaxies

TL;DR

IAC-pop is a genetic algorithm-based tool for deriving the star formation history of galaxies from color-magnitude diagrams, demonstrating robustness and providing error estimates through multiple runs.

Contribution

It introduces a new method using genetic algorithms for SFH recovery from CMDs, with internal consistency tests and error estimation procedures.

Findings

Robustness against observational errors and stellar evolution differences.

Multiple runs improve stability and error estimation.

Open-source availability for the astronomical community.

Abstract

IAC-pop is a code designed to solve the star formation history (SFH) of a complex stellar population system, like a galaxy, from the analysis of the color-magnitude diagram (CMD). It uses a genetic algorithm to minimize a chi2 merit function comparing the star distributions in the observed CMD and the CMD of a synthetic stellar population. A parametrization of the CMDs is used, which is the main input of the code. In fact, the code can be applied to any problem in which a similar parametrization of an experimental set of data and models can be made. The method internal consistency and robustness against several error sources, including observational effects, data sampling and stellar evolution library differences, are tested. It is found that the best stability of the solution and the best way to estimate errors is obtained by several runs of IAC-pop with varying the input data parametrization. The routine MinnIAC is used to control this process. IAC-pop is offered for free use and can be downloaded from the site http://iac-star.iac.es/iac-pop. The routine MInnIAC is also offered under request, but support can not be provided for its use. The only requirement for the use of IAC-pop and MinnIAC is referencing this paper and crediting as indicated in the site.