SDSS-IV MaNGA: The kinematic-morphology of galaxies on the mass versus star-formation relation in different environments

Journal Article · Thu May 14 00:00:00 EDT 2020 · Monthly Notices of the Royal Astronomical Society

DOI:https://doi.org/10.1093/mnras/staa1325· OSTI ID:1630970

Wang, Bitao  ^[1]; Cappellari, Michele  ^[2]; Peng, Yingjie ^[3]; Graham, Mark  ^[2]

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1. Department of Astronomy, School of Physics, Peking University, Beijing 100871, China, Kavli Institute for Astronomy and Astrophysics, Peking University, Beijing 100871, China, Sub-Department of Astrophysics, Department of Physics, University of Oxford, Denys Wilkinson Building, Keble Road, Oxford OX1 3RH, UK
2. Sub-Department of Astrophysics, Department of Physics, University of Oxford, Denys Wilkinson Building, Keble Road, Oxford OX1 3RH, UK
3. Kavli Institute for Astronomy and Astrophysics, Peking University, Beijing 100871, China

ABSTRACT We study the link between the kinematic-morphology of galaxies, as inferred from integral-field stellar kinematics, and their relation between mass and star formation rate. Our sample consists of ∼3200 galaxies with integral-field spectroscopic data from the MaNGA survey (Mapping Nearby Galaxies at Apache Point Observatory) with available determinations of their effective stellar angular momentum within the half-light radius $$\lambda _{R_e}$$. We find that for star-forming galaxies, namely along the star formation main sequence (SFMS), the $$\lambda _{R_e}$$ values remain large and almost unchanged over about two orders of magnitude in stellar mass, with the exception of the lowest masses $$\mathcal {M}_{\star }\lesssim 2\times 10^{9} \, \mathcal {M}_{\odot }$$, where $$\lambda _{R_e}$$ slightly decreases. The SFMS is dominated by spiral galaxies with small bulges. Below the SFMS, but above the characteristic stellar mass $$\mathcal {M}_{\rm crit}\approx 2\times 10^{11} \, \mathcal {M}_{\odot }$$, there is a sharp decrease in $$\lambda _{R_e}$$ with decreasing star formation rate (SFR): massive galaxies well below the SFMS are mainly slow-rotator early-type galaxies, namely genuinely spheroidal galaxies without discs. Below the SFMS and below $$\mathcal {M}_{\rm crit}$$ the decrease of $$\lambda _{R_e}$$ with decreasing SFR becomes modest or nearly absent: low-mass galaxies well below the SFMS, are fast-rotator early-type galaxies, and contain fast-rotating stellar discs like their star-forming counterparts. We also find a small but clear environmental dependence for the massive galaxies: in the mass range $$10^{10.9}\!-\!10^{11.5} \, \mathcal {M}_{\odot }$$, galaxies in rich groups or denser regions or classified as central galaxies have lower values of $$\lambda _{R_e}$$. While no environmental dependence is found for galaxies of lower mass. We discuss how the above results can be understood as due to the different star formation and mass assembly histories of galaxies with varying mass.

• Sponsoring Organization: USDOE
• OSTI ID: 1630970
• Journal Information: Monthly Notices of the Royal Astronomical Society, Journal Name: Monthly Notices of the Royal Astronomical Society Vol. 495 Journal Issue: 2; ISSN 0035-8711
• Publisher: Oxford University Press
• Country of Publication: United Kingdom
• Language: English