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We construct a suite of discrete chemo-dynamical models of the giant elliptical galaxy NGC 5846. These models are a powerful tool to constrain both the mass distribution and internal dynamics of multiple tracer populations. We use Jeans models to simultaneously fit stellar kinematics within the effective radius $R_{rm e}$, planetary nebula (PN) radial velocities out to $3, R_{rm e}$, and globular cluster (GC) radial velocities and colours out to $6,R_{rm e}$. The best-fitting model is a cored DM halo which contributes $sim 10%$ of the total mass within $1,R_{rm e}$, and $67% pm 10%$ within $6,R_{rm e}$, although a cusped DM halo is also acceptable. The red GCs exhibit mild rotation with $v_{rm max}/sigma_0 sim 0.3$ in the region $R > ,R_{rm e}$, aligned with but counter-rotating to the stars in the inner parts, while the blue GCs and PNe kinematics are consistent with no rotation. The red GCs are tangentially anisotropic, the blue GCs are mildly radially anisotropic, and the PNe vary from radially to tangentially anisotropic from the inner to the outer region. This is confirmed by general made-to-measure models. The tangential anisotropy of the red GCs in the inner regions could stem from the preferential destruction of red GCs on more radial orbits, while their outer tangential anisotropy -- similar to the PNe in this region -- has no good explanation. The mild radial anisotropy of the blue GCs is consistent with an accretion scenario.
We present a new discrete chemo-dynamical axisymmetric modeling technique, which we apply to the dwarf spheroidal galaxy Sculptor. The major improvement over previous Jeans models is that realistic chemical distributions are included directly in the
We study the mass and anisotropy distribution of the giant elliptical galaxy NGC 5846 using stars, as well as the red and blue globular cluster (GC) subpopulations. We break degeneracies in the dynamical models by taking advantage of the different ph
Large galaxies may contain an atmosphere of hot interstellar X-ray gas, and the temperature and radial density profile of this gas can be used to measure the total mass of the galaxy contained within a given radius r. We use this technique for 102 ea
Using new and archival data, we study the kinematic properties of the nearest field S0 galaxy, NGC 3115, out to $sim6.5$ half-light radii ($R_mathrm{e}$) from its stars (integrated starlight), globular clusters (GCs) and planetary nebulae (PNe). We f
We describe a new technique to measure stellar kinematics and line-strengths at large radii in nearby galaxies. Using the integral-field spectrograph SAURON as a photon-collector, we obtain spectra out to four effective radii (Re) in the early-type g