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I have analyzed line-of-sight velocity fields of the stellar and ionized-gas components for the volume-limited sample of nearby lenticular galaxies by using the raw data of the ATLAS-3D survey undertaken with the integral-field spectrograph SAURON. Among 200 nearby lenticular galaxies, I distinguish 20 cases of nearly orthogonal rotation of the inner ionized gas with respect to the central stellar components; so I estimate a frequency of the inner polar disks in nearby S0 galaxies as 10%. Properties of the central stellar populations – mean ages, metallicities, magnesium-to-iron ratios – are derived through the Lick indices. The typical stellar population properties of the polar-disk host galaxies are exactly the same as the stellar population properties of the complete sample. [ABSTRACT FROM PUBLISHER]

The presence of exponential bulges and anti-truncated disks has been noticed in many lenticular galaxies. In fact, it could be expected because the very formation of S0 galaxies includes various processes of secular evolution. We discuss how to distinguish between a pseudobulge and an anti-truncated disk, and also what particular mechanisms may be responsible for the formation of anti-truncated disks. Some clear examples of lenticular galaxies with a multi-tier exponential stellar structure are presented, – among them two central group giant S0s seen face-on and perfectly axisymmetric. [ABSTRACT FROM PUBLISHER]

Panoramic spectroscopy of the sample of 80 nearby lenticular galaxies is presented. The SSP-equivalent ages, [Z/H], and [Mg/Fe] are determined through the Lick indices Hβ, Mgb, and 〈Fe〉 separately for the nuclei and for the bulges. About a half of the sample contain chemically distinct nuclei, more metal-rich and younger than the bulges. The statistics of stellar population properties for the nearby S0s is discussed. [ABSTRACT FROM PUBLISHER]

What is the origin of the numerous population of diffuse elliptical galaxies (dE)? These galaxies formed their stars several billion years ago and lost their gas. Though the stellar winds resulting from star formation and the interactions with the environment undoubtedly play a role, their respective role and details of this evolution are still debated.In this presentation we will review the first 3D spectroscopic observations of a handful of dE galaxies. These data reveal complex kinematical structures, with embedded discs and counter rotating cores, and they open extremely promising perspectives for studying the history of the stellar population throughout these various features.The presence of disks, which was already known from detailed image analysis, their complex kinematics, and the new constraints on the stellar population enforce the hypothesis of the evolutionary connection between dEs and disk galaxies. [ABSTRACT FROM PUBLISHER]

By studying the radial distribution of the properties of stellar populations in 15 nearby S0 galaxies, I have found that the outer stellar disks are mostly old, with SSP-equivalent ages of 8–15 Gyr, often being older than the bulges. This fact throws doubt on the currently accepted paradigm that S0 galaxies were formed at z=0.4 through the quenching of star formation in spiral galaxies. [ABSTRACT FROM PUBLISHER]

We present a novel approach for simultaneous extraction of stellar population parameters and internal kinematics from the spectra integrated along a line of sight. We fit a template spectrum into an observed one in a pixel space using a non-linear χ2 minimization in the multidimensional parameter space, including characteristics of the line-of-sight velocity distribution (LOSVD) and parametrized star formation history (SFH). Our technique has been applied to IFU and multi-object spectroscopy of low-luminosity early type galaxies. [ABSTRACT FROM PUBLISHER]

We present first studies of dE galaxies by means of 3D spectroscopy, and address questions concerning data processing and analysis techniques used to extract internal kinematics and stellar population properties from integrated light spectra. [ABSTRACT FROM PUBLISHER]

The properties of stellar populations in the centers of nearby lenticular galaxies are investigated by means of 2D spectroscopy. All the galaxies are divided into 4 groups depending on the environment type; every subsample contains more than 10 galaxies. Clear distinctions between the mean stellar ages and abundance ratios are found both for the nuclei and for the bulges of the S0s in the different environments.To search for other articles by the author(s) go to: http://adsabs.harvard.edu/abstract_service.html [ABSTRACT FROM PUBLISHER]

By means of 2D spectroscopy we have found a lot of compact inner stellar and gaseous disks in morphologically normal galaxies. The evolution and spatial orientation of these inner structures are often decoupled from the evolution and spatial orientation of the large-scale galactic disks and bulges. We argue that this finding requires substantial change of common approaches to investigations of the central parts of galaxies, including central black hole studies.To search for other articles by the author(s) go to: http://adsabs.harvard.edu/abstract_service.html [ABSTRACT FROM PUBLISHER]