Yunnan-III models for Evolutionary population synthesis

Abstract

We build the Yunnan-III evolutionary population synthesis (EPS) models by using the MESA stellar evolution code, BaSeL stellar spectra library and the initial mass functions (IMFs) of Kroupa and Salpeter, and present colours and integrated spectral energy distributions (ISEDs) of solar-metallicity stellar populations (SPs) in the range of 1Myr-15 Gyr. The main characteristic of the Yunnan-III EPS models is the usage of a set of self-consistent solar-metallicity stellar evolutionary tracks (the masses of stars are from 0.1 to 100Msun). This set of tracks is obtained by using the state-of-the-art MESA code. MESA code can evolve stellar models through thermally pulsing asymptotic giant branch (TP-AGB) phase for low- and intermediate-mass stars. By comparisons, we confirm that the inclusion of TP-AGB stars make the V-K, V-J and V-R colours of SPs redder and the infrared flux larger at ages log(t/yr)>7.6 (the differences reach the maximum at log(t/yr)~8.6, ~0.5-0.2mag for colours, ~2 times for K-band flux). The stellar evolutionary tracks, isochrones, colours and ISEDs can be obtained on request from the first author or from our website (http://www1.ynao.ac.cn/~zhangfh/). Using the isochrones, you can build your EPS models. Now the format of stellar evolutionary tracks is the same as that in the STARBURST99 code, you can put them into the STARBURST99 code and get the SP's results. Moreover, the colours involving other passbands or on other systems (for example, HST $F439W-F555W$ colour on AB system) can also be obtained on request.