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Aims. The formation scenario of extended counter-rotating stellar disks in galaxies is still debated. In this paper, we study the S0 galaxy IC 719 known to host two large-scale counter-rotating stellar disks in order to investigate their formation mechanism. Methods. We exploit the large field of view and wavelength coverage of the Multi Unit Spectroscopic Explorer (MUSE) spectrograph to derive two-dimensional (2D) maps of the various properties of the counter-rotating stellar disks, such as age, metallicity, kinematics, spatial distribution, the kinematical and chemical properties of the ionized gas, and the dust map. Results. Due to the large wavelength range, and in particular to the presence of the Calcium Triplet λλ8498, 8542, 8662 Å (CaT hereafter), the spectroscopic analysis allows us to separate the two stellar components in great detail. This permits precise measurement of both the velocity and velocity dispersion of the two components as well as their spatial distribution. We derived a 2D map of the age and metallicity of the two stellar components, as well as the star formation rate and gas-phase metallicity from the ionized gas emission maps. Conclusions. The main stellar disk of the galaxy is kinematically hotter, older, thicker and with larger scale-length than the secondary disk. There is no doubt that the latter is strongly linked to the ionized gas component: they have the same kinematics and similar vertical and radial spatial distribution. This result is in favor of a gas accretion scenario over a binary merger scenario to explain the origin of counter-rotation in IC 719. One source of gas that may have contributed to the accretion process is the cloud that surrounds IC 719. [ABSTRACT FROM AUTHOR]

Aims. We here distinguish two counter-rotating stellar components in NGC 4191 and characterize their physical properties such as kinematics, morphology, age, and metallicity. Methods. We obtained integral field spectroscopic observations with VIRUS-W and used a spectroscopic decomposition technique to separate the contribution of two stellar components to the observed galaxy spectrum. We also performed a photometric decomposition, modeling the galaxy with a Sérsic bulge and two exponential disks of different scale length, with the aim of associating these structural components with the kinematic components. We then measured the equivalent width of the absorption line indices on the best-fit models that represent the kinematic components and compared our measurements to the predictions of stellar population models that also account for the variable abundance ratio of a elements. Results. We have evidence that the line-of-sight velocity distributions (LOSVDs) are bimodal and asymmetric, consistent with the presence of two distinct kinematic components. The combined information of the intensity of the peaks of the LOSVDs and the photometric decomposition allows us to associate the Sérsic bulge and the outer disk with the main kinematic component and to associate the inner disk with the secondary kinematic component. We find that the two kinematic stellar components counter-rotate with respect to each other. The main component is the most luminous and massive; the secondary component rotates along the same direction as the ionized gas. The study of the stellar populations reveals that the two kinematic components have the same solar metallicity and subsolar abundance ratio, without significant radial gradients. On the other hand, their ages show negative gradients and the possible indication that the secondary component is the younger. We interpret our results in light of recent cosmological simulations and suggest gas accretion along two filaments as the formation mechanism of the stellar counter-rotating components in NGC 4191. [ABSTRACT FROM AUTHOR]