2017MNRAS.470...20S

We performed long-slit spectral observations of two SB-type galaxies: NGC 5347 and UGC 1344. They were previously suspected as the galaxies with unusually low mass-to-light ratios (on the ground of mass estimates from the H I linewidths), which are in conflict with their observed colours. The observations were conducted at the Russian 6-m telescope. The aim of this study was to clarify the kinematics and structure, as well as the properties of stellar populations of the galaxies. The results of observations disproved the peculiarly low mass-to-light ratios of both galaxies. The most probable reasons of underestimation of their masses are discussed. We tried to reproduce the main observed features of kinematical profiles of the galaxies in the N-body simulations of barred galaxies. We found that both galaxies possess central components of different structures. Indeed, the age and velocity dispersion of stellar population in NGC 5347 are low in its innermost part in comparison to that of the bulge or a bar, which agrees with the presence of nuclear kinematically decoupled disc. It probably was formed due to the bar that supplied the inner region with gas. The kinematical profiles of the second galaxy UGC 1344 give evidence in favour of the central peanut-shaped bulge. In spite of the different luminosities of the two galaxies, they possess nearly equal (close to solar) central stellar abundance and the flattening of the stellar metallicity gradient in the bar regions. However, in the less luminous NGC 5347, the mean stellar age is younger than that in UGC 1344.