Tully-Fisher relation, galactic rotation curves and dissipative mirror
  dark matter
  If dark matter is dissipative then the distribution of dark matter within
galactic halos can be governed by dissipation, heating and hydrostatic
equilibrium. Previous work has shown that a specific model, in the framework of
mirror dark matter, can explain several empirical galactic scaling relations.
It is shown here that this dynamical halo model implies a quasi-isothermal dark
matter density, $\rho (r) = \rho_0 r_0^2/(r^2 + r_0^2)$, where the core radius,
$r_0$, scales with disk scale length, $r_D$, via $r_0/{\rm kpc} =
1.4\left(r_D/{\rm kpc}\right)$. Additionally, the product $\rho_0 r_0$ is
roughly $constant$, i.e. independent of galaxy size (the $constant$ is set by
the parameters of the model). The derived dark matter density profile implies
that the galactic rotation velocity satisfies the Tully-Fisher relation, $L_B
\propto v^{3}_{max}$, where $v_{max}$ is the maximal rotational velocity.
Examples of rotation curves resulting from this dynamics are given.
