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arXiv · 0711.4372

The elliptical galaxy NGC 5044: Stellar population and ionized gas

Abstract

In this work we investigate the stellar population, metallicity distribution and ionized gas in the elliptical galaxy NGC 5044, using long-slit spectroscopy and a stellar population synthesis method. We found differences in the slope of metal-line profiles along the galaxy which suggests an enhancement of alpha elements, particularly towards the central region. The presence of a non-thermal ionization source, such as a low-luminosity AGN and/or shock ionization, is implied by the large values of the ratio (N II])Ha observed in all sampled regions. However, the emission lines observed in the external regions indicate the presence of an additional ionization source, probably hot, post-AGB stars.

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M. G. Rickes, M. G. Pastoriza, Ch Bonatto. 2007-11-27. The elliptical galaxy NGC 5044: Stellar population and ionized gas. https://doi.org/10.1051/0004-6361%3A20034302

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