Mass distribution and kinematics of the barred galaxies NGC 3992 and NGC 7479

We present morphological and kinematical models for the intermediate-type b arred galaxies NGC 3992 and NGC 7479. Two-dimensional models of the observe d NIR surface brightness distributions with three components (bulge, bar, d isk) are used for the construction of corresponding models of the stellar m ass distribution. The resulting potentials are implemented numerically in a code for the computation of collisionless closed orbits for H-alpha clouds . These gas clouds serve as test particles in the potential and are used fo r the examination of the phase space and the construction of artificial gas rotation curves. The artificial rotation curves are confronted with observ ed H-alpha rotation curves. The model parameters of bulge, disk, and bar ar e adjusted by iteratively computing and evaluating a large number of differ ent models, until an optimal fit to the observations was obtained. The effe cts of changing single parameter values and possible error sources are disc ussed. Special emphasis is put on the role of bar asymmetries in the case o f NGC 7479 and the bar pattern speed in both objects. Final models are presented which reproduce the overall morphological struct ure (bulge, bar, disk) of NGC 3992 and NGC 7479 as well as the H-alpha rota tion curves with most of their details in a consistent manner. The paramete rs needed for an optimal representation of the H-alpha rotation curves and those derived morphologically are in very good agreement. It is shown that our modelling technique is able to explain the H-alpha velocity fields of b oth galaxies especially in the regions dominated by the bar component.