| Abstract | Newly observed H I 21-cm linewidths for eight galaxies and morphological types for 33 galaxies are combined with data in the literature to construct a homogeneous magnitude-limited sample of spiral galaxies in the Coma cluster. From this sample, we identify the seven Coma M31-like galaxies, i.e. the spiral members with inclinations i >= 44^deg^ and deprojected linewidths {DELTA}V_c_ >= 440 km s^-1^. The distance moduli of these seven galaxies obtained by application of a blue-band Tully-Fisher (TF) relation are used to measure the distance to the Coma cluster. Our result, which is free of `Malmquist' bias at the 36 level, is a distance modulus of μ^0^ = 34.4+/-0.2, which corresponds to a Hubble constant H_0_ ~ 90 km s^-1^ Mpc^-1^. The observed rms dispersion of blue-band TF distance moduli for the seven Coma M31-like galaxies is 0.14 mag, which is consistent with observational uncertainties alone, i.e. no intrinsic dispersion of the blue-band TF relation has been detected above the observational rms noise level of 0.14 mag. This small scatter is a specific result of our strict selection criteria adopted at the onset of the analysis. |
