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arXiv · 2202.03848

Different Formation Scenarios of Counter-rotating Stellar Disks in Nearby Galaxies

Min Bao·Yanmei Chen·Pengpei Zhu·Yong Shi·Dmitry Bizyaev·Ling Zhu·Meng Yang·Minje Beom·Joel R. Brownstein·Richard R. Lane
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Abstract

Using the integral field unit (IFU) data from Mapping Nearby Galaxies at Apache Point Observatory (MaNGA) survey, we select a sample of 101 galaxies with counter-rotating stellar disks and regularly-rotating ionized gas disk. We classify the 101 galaxies into four types based on the features of their stellar velocity fields. The relative fractions and stellar population age radial gradients of the four types are different in blue cloud (BC), green valley (GV) and red sequence (RS) populations. We suggest different formation scenarios for the counter-rotating stellar disks, and the key factors in the formation of counter-rotating stellar disks include: (1) the abundance of pre-existing gas in progenitor, (2) the efficiency in angular momentum consumption.

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Min Bao, Yanmei Chen, Pengpei Zhu, Yong Shi, Dmitry Bizyaev, Ling Zhu, Meng Yang, Minje Beom, Joel R. Brownstein, Richard R. Lane. 2022-02-08. Different Formation Scenarios of Counter-rotating Stellar Disks in Nearby Galaxies. https://doi.org/10.3847/2041-8213%2Fac52ad

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