Rotation Curve Decomposition for Size-Mass Relations of Bulge, Disk, and
  Dark Halo in Spiral Galaxies
  Rotation curves of more than one hundred spiral galaxies were compiled from
the literature, and deconvolved into bulge, disk, and dark halo using $\chi^2$
fitting in order to determine their scale radii and masses. Correlation
analyses were obtained of the fitting parameters for galaxies that satisfied
selection and accuracy criteria. Size-mass relations indicate that the sizes
and masses are positively correlated among different components in such a way
that the larger or more massive is the dark halo, the larger or more massive
are the disk and bulge. Empirical size-mass relations were obtained for bulge,
disk and dark halo by the least-squares fitting. The disk-to-halo mass ratio
was found to be systematically greater by a factor of three than that predicted
by cosmological simulations combined with photometry. A preliminary mass
function for dark halo was obtained, which is represented by the Schechter
function followed by a power law.
