MaNGA DynPop – III. Stellar dynamics versus stellar population relations in 6000 early-type and spiral galaxies: Fundamental Plane, mass-to-light ratios, total density slopes, and dark matter fractions

Zhu, Kai; Lu, Shengdong; Cappellari, Michele; Li, Ran; Mao, Shude; Gao, Liang; Ge, Junqiang

Abstract

We present dynamical scaling relations, combined with the stellar population properties, for a subsample of about 6000 nearby
galaxies with the most reliable dynamical models extracted from the full Mapping Nearby Galaxies at Apache Point Observatory
(MaNGA) sample of 10 000 galaxies. We show that the inclination-corrected mass plane for both early-type galaxies (ETGs) and
late-type galaxies (LTGs), which links dynamical mass, projected half-light radius Re, and the second stellar velocity moment
σe within Re, satisfies the virial theorem and is even tighter than the uncorrected one. We find a clear parabolic relation between
lg(M/L)e, the total mass-to-light ratio (M/L) within a sphere of radius Re, and lg σe, with the M/L increasing with σe and
for older stellar populations. However, the relation for ETGs is linear and the one for the youngest galaxies is constant. We
confirm and improve the relation between mass-weighted total density slopes γT and σe: γT become steeper with increasing
σe until lg(σe/km s−1) ≈ 2.2 and then remain constant around γT ≈ 2.2. The γT –σe variation is larger for LTGs than ETGs. At
fixed σe the total density profiles steepen with galaxy age and for ETGs. We find generally low dark matter fractions, median
fDM(<Re) = 8 per cent, within a sphere of radius Re. However, we find that fDM(<Re) depends on σe better than stellar mass:
dark matter increases to a median fDM(<Re) = 33 per cent for galaxies with σe 100 km s−1. The increased fDM(<Re) at low
σe explains the parabolic lg(M/L)e– lg σe relation.

Citation

Zhu, K., Lu, S., Cappellari, M., Li, R., Mao, S., Gao, L., & Ge, J. (2024). MaNGA DynPop – III. Stellar dynamics versus stellar population relations in 6000 early-type and spiral galaxies: Fundamental Plane, mass-to-light ratios, total density slopes, and dark matter fractions. Monthly Notices of the Royal Astronomical Society, 527(1), 706–730. https://doi.org/10.1093/mnras/stad3213

• Journal Article Type: Article
• Acceptance Date: Oct 17, 2023
• Online Publication Date: Oct 21, 2023
• Publication Date: 2024-01
• Deposit Date: Jan 31, 2024
• Publicly Available Date: Jan 31, 2024
• Journal: Monthly Notices of the Royal Astronomical Society
• Print ISSN: 0035-8711
• Publisher: Royal Astronomical Society
• Peer Reviewed: Peer Reviewed
• Volume: 527
• Issue: 1
• Pages: 706–730
• DOI: https://doi.org/10.1093/mnras/stad3213
• Public URL: https://durham-repository.worktribe.com/output/2188193
• Publisher URL: https://doi.org/10.1093/mnras/stad3213