I will present high-resolution rotation curves and mass models of neaby
(< 10 Mpc) dwarf galaxies culled from LITTLE THINGS. The high-resolution
HI observations ( 6" angular; < 2.6 km/s velocity resolution) of LITTLE
THINGS enable us to derive reliable rotation curves of the galaxies in a
homogeneous and consistent manner. The rotation curves are combined with
Spitzer archival 3.6 micron and ancillary optical UBV images to construct mass
models. The high quality multi-wavelength dataset significantly reduces
observational uncertainties and thus allows us to examine in detail the dark
matter distribution in the galaxies. We compare the central dark matter
distributions of the LITTLE THINGS sample galaxies with those of dwarf
galaxies from The HI Nearby Galaxy Survey (THINGS). From this, we find
that they are consistent with each other in terms of (1) the rotation curve shape,
showing a linear increase in the inner regions, and (2) a shallow slope of the
mass density in the inner parts, resulting in dark matter halos characterised by
a core. This is in contrast with classical dark-matter-only cosmological
simulations, which predict a steep rotation curve in the central region and steep
inner slope of the dark matter density profiles. Instead, our results are more in
line with shallower slopes found in LambdaCDM simulations of dwarf galaxies
in which the effect of baryonic feedback processes is included. If time allows,
I will finish the talk with the latest progress on ASKAP.