A discrete chemo-dynamical model of the giant elliptical galaxy NGC 5846: dark matter fraction, internal rotation, and velocity anisotropy out to six effective radii

摘要: We construct a suite of discrete chemo-dynamical models the giant elliptical galaxy NGC 5846. These are powerful tool to constrain both mass distribution and internal dynamics multiple tracer populations. use Jeans simultaneously fit stellar kinematics within effective radius $R_{\rm e}$, planetary nebula (PN) radial velocities out $3\, R_{\rm globular cluster (GC) colours $6\,R_{\rm e}$. The best-fitting model is cored DM halo which contributes $\sim 10\%$ total $1\,R_{\rm $67\% \pm although cusped also acceptable. red GCs exhibit mild rotation with $v_{\rm max}/\sigma_0 \sim 0.3$ in region $R > \,R_{\rm aligned but counter-rotating stars inner parts, while blue PNe consistent no rotation. tangentially anisotropic, mildly radially vary from anisotropic outer region. This confirmed by general made-to-measure models. tangential anisotropy regions could stem preferential destruction on more orbits, their -- similar this has good explanation. an accretion scenario.