Adaptive optics observations of the flattened nuclear star cluster in the nearby edge-on spiral galaxy NGC 4244 using the Gemini Near-Infrared Integral Field Spectrograph ( NIFS ) have revealed clear rotation .
Using these kinematics plus 2MASS photometry we construct a series of axisymmetric two-component particle dynamical models with our improved version of nmagic , a flexible \chi ^ { 2 } -made-to-measure code .
The models consist of a nuclear cluster disc embedded within a spheroidal particle population .
We find a mass for the nuclear star cluster of \mathrm { M } = 1.6 ^ { +0.5 } _ { -0.2 } \times 10 ^ { 7 } \mbox { $ M _ { \odot } $ } within \sim 42.4 pc ( 2 ^ { \prime \prime } ) .
We also explore the presence of an intermediate mass black hole and show that models with a black hole as massive as \mbox { $ M _ { \bullet } $ } = 5.0 \times 10 ^ { 5 } ~ { } \mbox { $ M _ { \odot } $ } are consistent with the available data .
Regardless of whether a black hole is present or not , the nuclear cluster is vertically anisotropic ( \beta _ { z } < 0 ) , as was found with earlier two-integral models .
We then use the models as initial conditions for N -body simulations .
These simulations show that the nuclear star cluster is stable against non-axisymmetric perturbations .
We also explore the effect of the nuclear cluster accreting star clusters at various inclinations .
Accretion of a star cluster with mass 13 \% that of the nuclear cluster is already enough to destroy the vertical anisotropy , regardless of orbital inclination .