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We investigate how the stellar rotational support changes as a function of spatially resolved stellar population age (⁠|$D_n4000$|⁠) and relative central stellar surface density (⁠|$\Delta \Sigma _1$|⁠) for MaNGA isolated/central disc galaxies. We find that the galaxy rotational support indicator |$\lambda _{R_\mathrm{e}}$| varies smoothly as a function of |$\Delta \Sigma _1$| and |$D_n4000$|⁠. |$D_n4000$| versus |$\Delta \Sigma _1$| follows a 'J-shape', with |$\lambda _{R_\mathrm{e}}$| contributing to the scatters. In this 'J-shaped' pattern rotational support increases with central |$D_n4000$| when |$\Delta \Sigma _1$| is low but decreases with |$\Delta \Sigma _1$| when |$\Delta \Sigma _1$| is high. Restricting attention to low- |$\Delta \Sigma _1$| (i.e. large-radius) galaxies, we suggest that the trend of increasing rotational support with |$D_n4000$| for these objects is produced by a mix of two different processes, a primary trend characterized by growth in |$\lambda _{R_\mathrm{e}}$| along with mass through gas accretion, on top of which disturbance episodes are overlaid, which reduce rotational support and trigger increased star formation. An additional finding is that star-forming galaxies with low |$\Delta \Sigma _1$| have relatively larger radii than galaxies with higher |$\Delta \Sigma _1$| at fixed stellar mass. Assuming that these relative radii rankings are preserved while galaxies are star forming then implies clear evolutionary paths in central |$D_n4000$| versus |$\Delta \Sigma _1$|⁠. The paper closes with comments on the implications that these paths have for the evolution of pseudo-bulges versus classical bulges. The utility of using |$\rm D_n4000$| – |$\Delta \Sigma _1$| to study |$\lambda _{R_\mathrm{e}}$| reinforces the notion that galaxy kinematics correlate both with structure and with stellar-population state, and indicates the importance of a multidimensional description for understanding bulge and galaxy evolution. [ABSTRACT FROM AUTHOR]

We try to understand the trends in the mass density slopes as a function of galaxy properties. We use the results from the best Jeans Anisotropic Modelling (JAM) of the integral-field stellar kinematics for near 6000 galaxies from the MaNGA DynPop project, with stellar masses |$10^9\ {\rm {\rm M}_{\odot }}\lesssim M_*\lesssim 10^{12}\ {\rm {\rm M}_{\odot }}$|⁠ , including both early-type and late-type galaxies. We use the mass-weighted density slopes for the stellar |$\overline{\gamma }_*$|⁠ , dark |$\overline{\gamma }_{_{\rm DM}}$| and total |$\overline{\gamma }_{_{\rm T}}$| mass from the MaNGA DynPop project. As previously reported, |$\overline{\gamma }_{_{\rm T}}$| approaches a constant value of |$\overline{\gamma }_{_{\rm T}}\approx 2.2$| for high σe galaxies, and flattens for |$\lg (\sigma _{\rm e}/{\rm km\ s^{-1}})\lesssim 2.3$| galaxies, reaching |$\overline{\gamma }_{_{\rm T}}\approx 1.5$| for |$\lg (\sigma _{\rm e}/{\rm km\ s^{-1}})\approx 1.8$|⁠. We find that total and stellar slopes track each other tightly, with |$\overline{\gamma }_{_{\rm T}}\approx \overline{\gamma }_*-0.174$| over the full σe range. This confirms the dominance of stellar matter within R e. We also show that there is no perfect conspiracy between baryonic and dark matter, as |$\overline{\gamma }_*$| and |$\overline{\gamma }_{_{\rm DM}}$| do not vary inversely within the σe range. We find that the central galaxies from TNG50 and TNG100 simulations do not reproduce the observed galaxy mass distribution, which we attribute to the overestimated dark matter fraction, possibly due to a constant IMF and excessive adiabatic contraction effects in the simulations. Finally, we present the stacked dark matter density profiles and show that they are slightly steeper than the pure dark matter simulation prediction of |$\overline{\gamma }_{_{\rm DM}}\approx 1$|⁠ , suggesting moderate adiabatic contraction in the central region of galaxies. Our work demonstrates the power of stellar dynamics modelling for probing the interaction between stellar and dark matter and testing galaxy formation theories. [ABSTRACT FROM AUTHOR]

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 R e, and the second stellar velocity moment σe within R e, satisfies the virial theorem and is even tighter than the uncorrected one. We find a clear parabolic relation between |$\lg (M/L)_{\rm e}$|⁠ , the total mass-to-light ratio (M / L) within a sphere of radius R e, and |$\lg \sigma _{\rm e}$|⁠ , 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 |$\overline{\gamma _{_{\rm T}}}$| and σe: |$\overline{\gamma _{_{\rm T}}}$| become steeper with increasing σe until |$\lg (\sigma _{\rm e}/{\rm km\, s^{-1}})\approx 2.2$| and then remain constant around |$\overline{\gamma _{_{\rm T}}}\approx 2.2$|⁠. The |$\overline{\gamma _{_{\rm T}}}\!-\!\sigma _{\rm e}$| 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 f DM(< R e) = 8 per cent, within a sphere of radius R e. However, we find that f DM(< R e) depends on σe better than stellar mass: dark matter increases to a median f DM(< R e) = 33 per cent for galaxies with |$\sigma _{\rm e}\lesssim 100$|  km s−1. The increased f DM(< R e) at low σe explains the parabolic |$\lg (M/L)_{\rm e}\!-\!\lg \sigma _{\rm e}$| relation. [ABSTRACT FROM AUTHOR]

This is the first paper in our series on the combined analysis of the Dynamics and stellar Population (DynPop) for the MaNGA survey in the final SDSS Data Release 17 (DR17). Here, we present a catalogue of dynamically determined quantities for over 10 000 nearby galaxies based on integral-field stellar kinematics from the MaNGA survey. The dynamical properties are extracted using the axisymmetric Jeans Anisotropic Modelling (JAM) method, which was previously shown to be the most accurate for this kind of study. We assess systematic uncertainties using eight dynamical models with different assumptions. We use two orientations of the velocity ellipsoid: either cylindrically aligned JAMcyl or spherically aligned JAMsph. We also make four assumptions for the models' dark versus luminous matter distributions: (1) mass-follows-light, (2) free NFW dark halo, (3) cosmologically constrained NFW halo, (4) generalized NFW dark halo, i.e. with free inner slope. In this catalogue, we provide the quantities related to the mass distributions (e.g. the density slopes and enclosed mass within a sphere of a given radius for total mass, stellar mass, and dark matter mass components). We also provide the complete models which can be used to compute the full luminous and mass distribution of each galaxy. Additionally, we visually assess the qualities of the models to help with model selections. We estimate the observed scatter in the measured quantities which decreases as expected with improvements in quality. For the best data quality, we find a remarkable consistency of measured quantities between different models, highlighting the robustness of the results. [ABSTRACT FROM AUTHOR]

Galaxy properties are known to correlate most tightly with the galaxy effective stellar velocity dispersion σe. Here, we look for additional trends at fixed σe using 1339 galaxies (M * ≳ 6 × 109 M⊙) with different morphologies in the MaNGA (DR14) sample with integral-field spectroscopy data. We focus on the gradients (γrms ≡ σ(R e/4)/σe) of the stellar root-mean-square velocity (⁠|$V_{\rm rms} \equiv \sqrt{V^2 + \sigma ^2}$|⁠), which we show traces the total mass density gradient γtot derived from dynamical models and, more weakly, the bulge fraction. We confirm that γrms increases with σe, age, and metallicity. We additionally find that these correlations still exist at fixed σe, where galaxies with larger γrms are found to be older and more metal-rich. It means that mass density gradients contain information of the stellar population which is not fully accounted for by σe. This result puts an extra constraint on our understanding of galaxy quenching. We compare our results with galaxies in the IllustrisTNG hydrodynamical simulations and find that, at fixed σe, similar trends exist with age, the bulge fraction, and the total mass density slope but, unlike observations, no correlation with metallicity can be detected in the simulations. [ABSTRACT FROM AUTHOR]

Galaxy properties are known to correlate most tightly with the galaxy effective stellar velocity dispersion σe. Here, we look for additional trends at fixed σe using 1339 galaxies (M * ≳ 6 × 109 M⊙) with different morphologies in the MaNGA (DR14) sample with integral-field spectroscopy data. We focus on the gradients (γrms ≡ σ(R e/4)/σe) of the stellar root-mean-square velocity (⁠|$V_{\rm rms} \equiv \sqrt{V^2 + \sigma ^2}$|⁠), which we show traces the total mass density gradient γtot derived from dynamical models and, more weakly, the bulge fraction. We confirm that γrms increases with σe, age, and metallicity. We additionally find that these correlations still exist at fixed σe, where galaxies with larger γrms are found to be older and more metal-rich. It means that mass density gradients contain information of the stellar population which is not fully accounted for by σe. This result puts an extra constraint on our understanding of galaxy quenching. We compare our results with galaxies in the IllustrisTNG hydrodynamical simulations and find that, at fixed σe, similar trends exist with age, the bulge fraction, and the total mass density slope but, unlike observations, no correlation with metallicity can be detected in the simulations. [ABSTRACT FROM AUTHOR]

We derive the mass-weighted total density slopes within the effective (half-light) radius, γ′, for more than 2000 nearby galaxies from the SDSS-IV (Sloan Digital Sky Survey IV) MaNGA survey using Jeans-anisotropic-models applied to integral field unit observations. Our galaxies span a wide range of the stellar mass (109 M⊙ < M * < 1012 M⊙) and the velocity dispersion (30 km s−1 < σ v < 300 km s−1). We find that for galaxies with velocity dispersion σ v > 100 km s−1, the density slope has a mean value 〈γ′〉 = 2.24 and a dispersion σγ = 0.22, almost independent of velocity dispersion, consistent with previous lensing and stellar dynamical analysis. We also quantitatively confirm with high accuracy a turnover in the γ′–σ v relation is present at σ ∼ 100 km s−1, below which the density slope decreases rapidly with σ v , consistent with the results reported by previous analysis of |${\rm ATLAS^{\rm 3D}}$| survey. Our analysis shows that a large fraction of dwarf galaxies (below M * = 1010 M⊙) have total density slopes shallower than 1, which implies that they may reside in cold dark matter haloes with shallow density slopes. We compare our results with that of galaxies in hydrodynamical simulations of EAGLE, Illustris, and IllustrisTNG projects, and find all simulations predict shallower density slopes for massive galaxies with high σ v . Finally, we explore the dependence of γ′ on the positions of galaxies in haloes, namely centrals versus satellites, and find that for the same velocity dispersion, the amplitude of γ′ is higher for satellite galaxies by about 0.1. [ABSTRACT FROM AUTHOR]

Motivated by the recently discovered kinematic 'Hubble sequence' shown by the stellar orbit-circularity distribution of 260 CALIFA galaxies, we make use of a comparable galaxy sample at z  = 0 with a stellar mass range of |$M_{*}/\mathrm{M}_{\odot }\in [10^{9.7},\, 10^{11.4}]$| selected from the IllustrisTNG simulation and study their stellar orbit compositions in relation to a number of other fundamental galaxy properties. We find that the TNG100 simulation broadly reproduces the observed fractions of different orbital components and their stellar mass dependences. In particular, the mean mass dependences of the luminosity fractions for the kinematically warm and hot orbits are well reproduced within model uncertainties of the observed galaxies. The simulation also largely reproduces the observed peak and trough features at |$M_{*}\approx 1\rm {-}2\times 10^{10}\, \mathrm{M}_{\odot }$| in the mean distributions of the cold- and hot-orbit fractions, respectively, indicating fewer cooler orbits and more hotter orbits in both more- and less-massive galaxies beyond such a mass range. Several marginal disagreements are seen between the simulation and observations: the average cold-orbit (counter-rotating) fractions of the simulated galaxies below (above) |$M_{*}\approx 6\times 10^{10}\, \mathrm{M}_{\odot }$| are systematically higher than the observational data by |$\lesssim 10{{\ \rm per\ cent}}$| (absolute orbital fraction); the simulation also seems to produce more scatter for the cold-orbit fraction and less so for the non-cold orbits at any given galaxy mass. Possible causes that stem from the adopted heating mechanisms are discussed. [ABSTRACT FROM AUTHOR]