We present radial profiles of the surface mass density (SMD) in spiralgalaxies directly calculated using rotation curves (RC) on two approximationsof flat-disk (SMD-F) and spherical mass distribution (SMD-S). The SMDs arecombined with surface brightness (SB) using photometric data to derive radialvariations of the mass-to-luminosity ratio (ML). It is found that ML hasgenerally a central peak or a plateau, and decreases to a local minimum at$R\sim 0.1-0.2 h$, where $R$ is the radius and $h$ is the scale radius ofoptical disk. The ML ratio, then, increases rapidly till $\sim 0.5h$, and isfollowed by gradual rise till $\sim 2h$, remaining at around ML$\sim 2$ in w1band (infrared $\lambda$ 3.4 $\mu$m) and $\sim 10\ [M_\odot L_\odot^{-1}]$ inr-band ($\lambda$6200-7500 A). Beyond this radius, ML steeply increases towardthe observed edges at $R\sim 5h$, attaining values as high as ML$\sim 20$ in w1and $\sim 10^2\ [M_\odot L_\odot^{-1}]$ in r-band, indicative of dominant darkmatter. The general properties of the ML distributions will be useful toconstrain cosmological formation models of spiral galaxies. The radial profilesof the RC, SMD, and ML are available in pdf/eps figures and machine-readabletables as an archival atlas at URLhttp://www.ioa.s.u-tokyo.ac.jp/$\sim$sofue/smd2018/ and as the supplementarydata on PASJ home page.
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