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We present mass models for the dark matter component of seven dwarf galaxiestaken from "The HI Nearby Galaxy Survey" (THINGS) and compare these with thosefrom numerical Lambda Cold Dark Matter (LCDM) simulations. The THINGShigh-resolution data significantly reduce observational uncertainties and thusallow us to derive accurate dark matter distributions in these systems. We hereuse the bulk velocity fields when deriving the rotation curves of the galaxies.Compared to other types of velocity fields, the bulk velocity field minimizesthe effect of small-scale random motions more effectively and traces theunderlying kinematics of a galaxy more properly. The "Spitzer Infrared NearbyGalaxies Survey" (SINGS) 3.6 micron and ancillary optical data are used forseparating the baryons from their total matter content in the galaxies. Thesample dwarf galaxies are found to be dark matter dominated over most radii. Wefind discrepancies between the derived dark matter distributions of thegalaxies and those of LCDM simulations, even after corrections for non-circularmotions have been applied. The observed solid body-like rotation curves of thegalaxies rise too slowly to reflect the cusp-like dark matter distribution inCDM halos. Instead, they are better described by core-like models such aspseudo-isothermal halo models dominated by a central constant-density core. Themean value of the logarithmic inner slopes of the mass density profiles isalpha = -0.29 +- 0.07. They are significantly different from the steep slope of~ -1.0 inferred from previous dark-matter-only simulations, and are moreconsistent with shallower slopes found in recent LCDM simulations of dwarfgalaxies in which the effects of baryonic feedback processes are included.

Dark and luminous matter in THINGS dwarf galaxies