Diffuse post-starburst galaxies: a smoking gun of formation of ultra-diffuse galaxies via ram pressure stripping
Autor: | Kirill A. Grishin, Igor Chilingarian, Daniel G. Fabricant, Anton V. Afanasiev, Ivan Yu. Katkov |
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Rok vydání: | 2018 |
Předmět: |
Physics
010308 nuclear & particles physics Astronomy and Astrophysics Astrophysics::Cosmology and Extragalactic Astrophysics Astrophysics 01 natural sciences Galaxy Ram pressure Space and Planetary Science 0103 physical sciences Astrophysics::Solar and Stellar Astrophysics Astrophysics::Earth and Planetary Astrophysics 010303 astronomy & astrophysics Astrophysics::Galaxy Astrophysics |
Zdroj: | Proceedings of the International Astronomical Union. 14:365-368 |
ISSN: | 1743-9221 1743-9213 |
Popis: | Ultra-diffuse galaxies (UDGs) have sizes comparable to the Milky Way and stellar masses of about 1/1000 of it. They attracted a lot of attention as possible “dark galaxies” heavily dominated by dark matter, however, no reliable dynamical mass estimates were done because of their extremely low surface brightness. We have recently found 13 gas free diffuse young (300–500 Myr) post-starburst galaxies (PSGs) without ongoing star formation in Coma and Abell 2147, which, should they continue to evolve passively, will become UDGs in 5 Gyr. We obtained deep spectroscopic observations for 11 diffuse PSGs and derived their internal kinematics and stellar population properties. All of them possess disk-like kinematics (substantial rotation, low stellar velocity dispersion) and likely experienced starburst episodes prior to the star formation quenching by ram pressure stripping. Our results suggest that at least some UDGs were “normal” intermediate to large-sized disk galaxies in the past, which were later quenched by dense environment. |
Databáze: | OpenAIRE |
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