Presentation #105.02 in the session “Dynamics of Dark Matter”.
We demonstrate a new technique for estimating halo spin and concentration for an observed low luminosity dwarf barred galaxy UGC5288 with a combination of semianalytical techniques and N-body/SPH simulations. Dark matter halo properties are very well studied using the most up to date large scale cosmological hydrodynamical simulations. On the other hand, observationally it is very challenging to estimate dark matter halo properties, such as their velocity distributions and 3D mass distributions. We present a self-consistent method to constrain the host dark matter halo properties by forward modeling an observed galaxy’s disk properties, including stellar and gas surface densities, disk scale length, HI rotation curve and bar instabilities in the disk .Using the forward modeling approach, we can relate the disk properties to the halo properties, such as halo spin and concentration, which cannot be observed directly. We simulate UGC5288’s dark matter halo with both a Hernquist and pseudo-isothermal profile, and find the best match with a pseudo-isothermal halo model with core radius rc = 0.23 kpc and high halo spin Λ = 0.08 at the virial radius. These findings are consistent with previous rotation curve measurements of UGC5288, and as well as the theoretically predicted high spins of dwarf LSB galaxies. We are further developing an automated pipeline to implement this technique on a larger number of observed galaxies that will be potentially very useful for statistical studies of galaxy-halo formation.