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arXiv · 2207.02216

Luminosity Distribution of Dwarf Elliptical-like Galaxies

Mira Seo·Hong Bae Ann
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Abstract

We present the structural parameters of $\sim910$ dwarf elliptical-like galaxies in the local universe ($z\lesssim0.01$) derived from the $r-$band images of the Sloan Digital Sky Survey (SDSS). We examine the dependence of structural parameters on the morphological types (dS0, dE,dE$_{bc}$, dSph, and dE$_{blue}$). There is a significant difference in the structural parameters among the five sub-types if we properly treat the light excess due to nucleation in dSph and dE galaxies. The mean surface brightness within the effective radius ($<\mu_{e}>$) of dSph galaxies is also clearly different from that of other sub-types. The frequency of disk features such as spiral arms depends on the morphology of dwarf galaxies. The most pronounced difference between dSph galaxies and other sub-types of early-type dwarf galaxies is the absence of disk feature which is thought to be closely related to their origin.

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Mira Seo, Hong Bae Ann. 2022-07-05. Luminosity Distribution of Dwarf Elliptical-like Galaxies. https://doi.org/10.1093/mnras%2Fstac1719

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