| Abstract | A study of the H I properties and mass distribution of the Sculptor group galaxy NGC 247, from VLA observations, is presented. The H I disk turns out to be fairly small with a diameter comparable to the optical. The total H I mass is 8.0X 10^8^ M_sun_. From the velocity field, a systemic velocity V_sys_ = 161 km s^-1^, an inclination i = 74^deg^, and a position angle P.A. = 170^deg^ are found. The derived rotation curve is not flat, but rising out to the last observed point. Differences of~20 kms^- 1^ are seen between both sides (approaching and receding) of the galaxy. A study of the mass distribution suggests a (M/L_B_). = 4.0 for the stellar disk. For the dark halo, the best-fit model gives r_c_ = 24.2 kpc and ρ_0_ = 0.0046 M_sun_ pc^-3^. While the (M/L_B_). is well defined, the halo parameters are not well constrained. At the last point of rotation curve, (M/L_B_)_global_~ 11. |
