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Spatially Resolved Studies of Local Massive Red Spiral Galaxies

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 نشر من قبل Cai-Na Hao
 تاريخ النشر 2019
  مجال البحث فيزياء
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We report two-dimensional spectroscopic analysis of massive red spiral galaxies ($M_{*}$ $>$ 10$^{10.5}$ $M_{odot}$) and compare them to blue spiral and red elliptical galaxies above the same mass limit based on the public SDSS DR15 MaNGA observations. We find that the stellar population properties of red spiral galaxies are more similar to those of elliptical galaxies than to blue spiral galaxies. Red spiral galaxies show a shallow mass-weighted age profile, and they have higher stellar metallicity and Mgb/${rm langle Fe rangle}$ across the whole 1.5$R_{rm e}$ as compared to blue spirals, but all these properties are close to those of elliptical galaxies. One scenario to explain this is that red spirals form as remnants of very gas-rich major mergers that happened above $z$$sim$1.

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