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We present high resolution CO(1-0) interferometric observations and deep HSTB-V-I images of the flocculent isolated Sc type spiral NGC 4414. The goal is todetermine the stellar mass-to-light (M/L) ratio in a galactic disk. The starsare seen without a dust screen, the central gas mass is very low (undetected),and we show that the dark matter is negligible in the central regions. We havedeveloped an axisymmetric analytical gravitational potential model to accountfor the central light (mass) profile, the dynamics of the molecular gas in thehighly obscured molecular ring, and the stellar light profile outside thehighly obscured region. The contribution of dark matter is constrained by theextremely extended HI rotation curve and is small, possibly negligible, atdistances less than 5 -- 7 kpc from the center. Furthermore, the M/L ratios wederive are low, about 1.5 in I band and 0.5 in K' band. The B and V band M/Lratios vary greatly due to absorption by dust, reaching 4 in the molecular ringand decreasing to about 1.6 -- 1.8 at larger radii. This unequivocally showsthat models, like most maximum disk models, assuming constant M/L ratios in anoptical waveband, simply are not appropriate. We illustrate this by making mockmaximum disk models with a constant V band M/L ratio. The key is having thecentral light distribution unobscured such that it can be used to trace themass. A primitive attempt to determine the intrinsic M/L ratio yields valuesclose to unity in the B,V, and I bands and slightly below 0.5 in K'.Comment: 12 pages, 10 figures, accepted in A&

The stellar mass to light ratio in the isolated spiral NGC 4414