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arXiv · 1510.08179

Isolated Galaxies versus Interacting Pairs with MaNGA

M. Argudo-Fernández·F. Yuan·S. Shen·J. Yin·R. Chang·S. Feng
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Abstract

We present preliminary results of the spectral analysis on the radial distributions of the star formation history in both, a galaxy merger and a spiral isolated galaxy observed with MaNGA. We find that the central part of the isolated galaxy is composed by older stellar population ($\sim$2 Gyr) than in the outskirts ($\sim$7 Gyr). Also, the time-scale is gradually larger from 1 Gyr in the inner part to 3 Gyr in the outer regions of the galaxy. In the case of the merger, the stellar population in the central region is older than in the tails, presenting a longer time-scale in comparison to central part in the isolated galaxy. Our results are in agreement with a scenario where spiral galaxies are built from inside-out. In the case of the merger, we find evidence that interactions enhance star formation in the central part of the galaxy.

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M. Argudo-Fernández, F. Yuan, S. Shen, J. Yin, R. Chang, S. Feng. 2015-10-28. Isolated Galaxies versus Interacting Pairs with MaNGA. https://doi.org/10.3390/galaxies3040156

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