Breaking the disc-halo degeneracy in NGC 1291 using hydrodynamic
  simulations
  We present a pilot study on the nearby massive galaxy NGC 1291, in which we
aim to constrain the dark matter in the inner regions, by obtaining a dynamical
determination of the disc mass-to-light ratio (M/L). To this aim, we model the
bar-induced dust lanes in the galaxy, using hydrodynamic gas response
simulations. The models have three free parameters, the M/L of the disc, the
bar pattern speed and the disc height function. We explore the parameter space
to find the best fit models, i.e. those in which the morphology of the shocks
in the gas simulations matches the observed dust lanes. The best-fit models
suggest that the M/L of NGC 1291 agrees with that predicted by stellar
population synthesis models in the near-infrared
($\approx$0.6\,$M_{\odot}/L_{\odot}$), which leads to a borderline maximum disc
for this galaxy. The bar rotates fast, with corotation radius $\leq$ 1.4 times
the bar length. Additionally, we find that the height function has a
significant effect on the results, and can bias them towards lower or higher
M/L.
