The kinematics and stellar populations of the low-mass nearby S0 galaxy NGC 5102 are studied from integral field spectra taken with the Multi-Unit Spectroscopic Explorer ( MUSE ) .
The kinematic maps reveal for the first time that NGC 5102 has the characteristic 2 \sigma peaks indicative of galaxies with counter-rotating discs .
This interpretation is quantitatively confirmed by fitting two kinematic components to the observed spectra .
Through stellar population analysis we confirm the known young stellar population in the centre and find steep age and metallicity gradients .
We construct axisymmetric Jeans anisotropic models of the stellar dynamics to investigate the initial mass function ( IMF ) and the dark matter halo of the galaxy .
The models show that this galaxy is quite different from all galaxies previously studied with a similar approach : even within the half-light radius , it can not be approximated with the self-consistent mass-follows-light assumption .
Including an NFW dark matter halo , we need a heavy IMF and a dark matter fraction of 0.37 \pm 0.04 within a sphere of one R _ { e } radius to describe the stellar kinematics .
The more general model with a free slope of the dark matter halo shows that slope and IMF are degenerate , but indicates that a light weight IMF ( Chabrier-like ) and a higher dark matter fraction , with a steeper ( contracted ) halo , fit the data better .
Regardless of the assumptions about the halo profile , we measure the slope of the total mass density to be -1.75 \pm 0.04 .
This is shallower than the slope of -2 of an isothermal halo and shallower than published slopes for more massive early type galaxies .