Modelling the Milky Way through adiabatic compression of cold dark matter haloes

We use the adiabatic compression theory to build a physically well-motivated Milky Way mass model in agreement with observational data. The visible mass of the Galaxy is distributed in a spheroidal bulge and a multi-component disc parametrized by three galactic parameters, the Sun distance to the galactic centre, R-0, the total bulge mass, Mbulge, and the local disc surface density, Sigma(circle dot). To model the dark matter component, we adiabatically compress a Navarro, Frenk and White (NFW) halo ( with concentration c and total mass M-vir) for fixed values of the spin parameter., the fraction of the mass in baryons m(b), and the thin disc contribution to total angular momentum j(d). An iterative selection procedure is used to explore in detail the wide space of parameters only selecting those combinations of { R-0, M-bulge, Sigma(circle dot) .lambda, m(b), j(d), M-vir } that give rise to a Milky Way model in agreement with observational constraints. This analysis leads us to conclude that only models with R-0 = 8.5 kpc, 0.8 x 10(10) M-circle dot < M-bulge < 1.6 x 10(10) M-circle dot and 49 M-circle dot pc(-2) <= Sigma(circle dot) <= = 56(circle dot) pc(- 2) can be reconciled with the set of observational constraints. As regards the parameters entering the adiabatic compression, we find 0.03 <= lambda <= 0.10 and 0.04 <= m(b) <= 0.10, while final estimates of the parameters describing the initial halo profile turn out to be 5 <= c <= 12 and 7 x 10(11) M-circle dot less than or similar to M-vir less than or similar to 17 x 10(11) M-circle dot ( all at 95.7% CL).