Metallicity-dependent spectral evolution

P. Traat

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arXiv · astro-ph/9812425

Metallicity-dependent spectral evolution

P. Traat

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Abstract

We have studied the spectral evolution of stellar populations in function of their heavy element content and star formation, using Geneva and Padova stellar track sets, both covering a number of metallicities, and Kurucz grid of stellar atmospheres. The general trend is the progressive growth of absorption and decline of flux towards shorter, UV-wavelengths, with increasing metallicity, and increase of infrared flux. Our models help to quantify given theoretically quite obvious effect. Presented results of integration of flux in different regions indicate, that with a change of metallicity from Z=0.001 to Z=0.04 total amount of radiation energy emitted in the shortest wavelength region by a stellar population during its lifetime diminishes typically by a factor ~10, with the corresponding typical increase in the infrared about 1.5-2 times. These numbers are quite independent on the actual IMF slope values under the assumption of identical slopes.

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P. Traat. 1998-12-23. Metallicity-dependent spectral evolution. https://arxiv.org/abs/astro-ph/9812425

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