We perform in-depth dynamical modelling of the luminous and dark matter ( DM ) content of the elliptical galaxy NGC 1407 .
Our strategy consists of solving the spherical Jeans equations for three independent dynamical tracers : stars , blue GCs and red GCs in a self-consistent manner .
We adopt a maximum-likelihood Markov-Chain Monte Carlo fitting technique in the attempt to constrain the inner slope of the DM density profile ( the cusp/core problem ) , and the stellar initial mass function ( IMF ) of the galaxy .
We find the inner logarithmic slope of the DM density profiles to be \gamma = 0.6 \pm 0.4 , which is consistent with either a DM cusp ( \gamma = 1 ) or with a DM core ( \gamma = 0 ) .
Our findings are consistent with a Salpeter IMF , and marginally consistent with a Kroupa IMF .
We infer tangential orbits for the blue GCs , and radial anisotropy for red GCs and stars .
The modelling results are consistent with the virial mass–concentration relation predicted by \Lambda CDM simulations .
The virial mass of NGC 1407 is \log M _ { vir } = 13.3 \pm 0.2 M _ { \sun } , whereas the stellar mass is \log M _ { * } = 11.8 \pm 0.1 M _ { \sun } .
The overall uncertainties on the mass of NGC 1407 are only 5 per cent at the projected stellar effective radius .
We attribute the disagreement between our results and previous X-ray results to the gas not being in hydrostatic equilibrium in the central regions of the galaxy .
The halo of NGC 1407 is found be DM dominated , with a dynamical mass-to-light ratio of M / L = 260 _ { -100 } ^ { +174 } M _ { \sun } / L _ { \sun,B } .
However , this value can be larger up to a factor of 3 depending on the assumed prior on the DM scale radius .