Full-Fledged Dwarf Irregular Galaxy Leo A

Vladas Vansevicius; Nobuo Arimoto; Takashi Hasegawa; Chisato Ikuta; Pascale Jablonka; Donatas Narbutis; Kouji Ohta; Rima Stonkute; Naoyuki Tamura; Valdas Vansevicius; Yoshihiko Yamada

doi:10.1086/423802

arXiv · astro-ph/0405313

Full-Fledged Dwarf Irregular Galaxy Leo A

Vladas Vansevicius·Nobuo Arimoto·Takashi Hasegawa·Chisato Ikuta·Pascale Jablonka·Donatas Narbutis·Kouji Ohta·Rima Stonkute·Naoyuki Tamura·Valdas Vansevicius·Yoshihiko Yamada

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Abstract

We have studied Leo A - the isolated and extremely gas rich dwarf irregular galaxy of very low stellar mass and metallicity. Ages of the stellar populations in Leo A are ranging from ~10 Myr to ~10 Gyr. Here we report the discovery of an old stellar halo and a sharp stellar edge. Also we find the distribution of stars extending beyond the gaseous envelope of the galaxy. Therefore, Leo A by its structure as well as stellar and gaseous content is found to resemble massive disk galaxies. This implies that galaxies of very low stellar mass are also able to develop complex structures, challenging contemporary understanding of galaxy evolution.

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Vladas Vansevicius, Nobuo Arimoto, Takashi Hasegawa, Chisato Ikuta, Pascale Jablonka, Donatas Narbutis, Kouji Ohta, Rima Stonkute, Naoyuki Tamura, Valdas Vansevicius, Yoshihiko Yamada. 2004-05-17. Full-Fledged Dwarf Irregular Galaxy Leo A. https://doi.org/10.1086/423802

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