We first present a recently developed three-dimensional chemodynamic code for galaxy evolution from the Kiev–Kiel collaboration. It follows the evolution of all components of a galaxy, such as dark matter, stars, molecular clouds and diffuse interstellar matter. Dark matter and stars are treated as collisionless N-body systems. The interstellar matter is numerically described by a smoothed particle hydrodynamics approach for the diffuse (hot) gas and a sticky particle scheme for the (cool) molecular clouds. Physical processes, such as star formation, stellar death, or condensation and evaporation processes of clouds interacting with the ISM are described locally. An example application of the model to a star forming dwarf galaxy will be shown for comparison with other codes. Secondly, we will discuss new kinds of exotic chemodynamic processes, as they occur in dense gas–star systems in galactic nuclei, such as non-standard ‘drag’-force interactions, destructive and gas-producing stellar collisions. Their implementation in one-dimensional dynamic models of galactic nuclei is presented. Future prospects to generalise these to three dimensions are in progress and will be discussed.

We follow the dynamical and chemical evolution of isolated systems tuned in their properties on selfgravitating spherical three component (gas+stars+dark matter) dwarf spheroidal galaxies (dSph). The system starts as a strongly dark matter dominated cuspy density profile. It is shown that after few Gyr of evolution the star formation processes are naturally able to reshape the cuspy dark matter profile into a flatter one. The same family of models is then evolved by orbiting in a Milky Way external potential in order to investigate the history of the Carina dwarf galaxy. Structural parameters and the star formation history of Carina are self-consistently determined in good agreement with the observations.

The young star clusters we observe today are the building blocks of a new generation of stars and planets in our Galaxy and beyond. Despite their fundamental role we still lack knowledge about the initial conditions under which star clusters form and the impact of these often harsh environments on the formation and evolution of their stellar and substellar members.

We present recent results showing that mass segregation in realistic models of young star clusters occurs very quickly for subvirial spherical systems without substructure. This finding is a critical step to resolve the controversial debate on mass segregation in young star clusters and provides strong constraints on their initial conditions. The rapid concentration of massive stars is usually associated with strong gravitational interactions early on during cluster evolution and the subsequent formation of multiple systems and ejection of stars.

A model of an isolated dwarf spherical galaxy (dSph) is considered in its chemo-dynamical evolution with time. The system is composed by 3 γ-model density profiles: gas, stellar and dark matter, and it is realized in a spherical symmetric equilibrium configuration. The total masses used in our simulations are covering the dwarf galaxies mass range. The stability of this configuration is first tested for the system evolving under the gravity effect alone and then evolved taking into account for the most relevant stellar astrophysical processes implemented with a Smooth Particle Hydrodynamic approach. The two different kinds of evolution are compared. The dark matter evolves naturally from a centrally cuspy density profile into a flatter one within a timescale of several Gyr. The effect manifests itself naturally, without any tuned initial conditions, as soon as few standard criteria on star formation are assumedand the SN feedback on the ISM has been adopted the prescription in (Cioffi & Shull 1991) and (Bradamante et al. 1998). This result is expected to be a possible natural explanation for the discrepancy between observations that want flatter dark matter profiles (e.g. de Block 2005), and N-body simulations that predict cuspy dark matter profiles (Navarro et al. 1997). Chemical considerations are presented as a tool to follow with observational parameters the theory predictions.

Stellar mass compact object binaries are promising sources of gravitational radiation for the current generation of ground-based detectors, VIRGO and LIGO. Accurate templates for gravitational waveforms are needed in order to extract an event from the VIRGO/LIGO data stream. In the case of relativistic, compact object binaries accurate orbital parameters are necessary in order to produce such templates. Binary systems are affected by their stellar environment and thus the parameters of the binary population of a dense star cluster will be different from those of the field population. We propose to investigate the parameters of relativistic binary populations in dense star clusters using direct N-body simulations with a Post-Newtonian treatment of general relativity for the close binaries.

Evolution of self-gravitating rotating dense stellar systems (e.g. globular clusters) with embedded black holes is investigated. The interplay between velocity diffusion due to relaxation and black hole star accretion is followed together with cluster differential rotation using 2D+1 Fokker Planck numerical methods. The models can reproduce the Bahcall-Wolf f ∝ E1/4 (∝ r−7/4) cusp inside the zone of influence of the black hole. Angular momentum transport and star accretion processes support the development of central rotation in relaxation time scales, before re-expansion and cluster dissolution due to mass loss in the tidal field of a parent galaxy. Gravogyro and gravothermal instabilities conduce the system to a faster evolution leading to shorter collapse times with respect to models without black hole.

We study the formation, growth, and co-evolution of single and multiple supermassive black holes (SMBHs) and compact objects like neutron stars, white dwarfs, and stellar mass black holes in galactic nuclei and star clusters, focusing on the role of stellar dynamics. In this paper we focus on one exemplary topic out of a wider range of work done, the study of orbital parameters of binary black holes in galactic nuclei (binding energy, eccentricity, relativistic coalescence) as a function of initial parameters. In some cases the classical evolution of black hole binaries in dense stellar systems drives them to surprisingly high eccentricities, which is very exciting for the emission of gravitational waves and relativistic orbit shrinkage. Such results are interesting to the emerging field of gravitational wave astronomy, in relation to a number of ground and space based instruments designed to measure gravitational waves from astrophysical sources (VIRGO, Geo600, LIGO, LISA). Our models self-consistently cover the entire range from Newtonian dynamics to the relativistic coalescence of SMBH binaries.

A major goal of contemporary astrophysics is understanding the origin of the most massive galaxies in the universe, particularly nearby ellipticals and spirals. Theoretical models of galaxy formation have existed for many decades, although observational evidence at both low and high redshifts is only beginning to put constraints on different ideas. We briefly describe these observations and how they are revealing the methods by which galaxies form by contrasting and comparing fiducial rapid collapse and hierarchical formation model predictions. The available data show that cluster ellipticals must have rapidly formed at z > 2, and that up to 50% of all massive galaxies at z ~ 2.5 are involved in major mergers. While the former is consistent with the monolithic collapse picture, we argue that hierarchical formation is the only model that can reproduce all the available observations.

New GSC-II proper motions of RR Lyrae and Blue Horizontal Branch (BHB) stars near the North Galactic Pole are used to show that the Galactic Halo 5 kpc above the Plane has a significantly retrograde galactic rotation.

We summarize results from the first year of the Lenses Structure and Dynamics Survey (LSD). Using the Echelle Imager and Spectrograph at the Keck-II Telescope, we have measured spatially resolved velocity dispersion profiles of a sample of distant (up to z=1) early-type galaxies that are gravitational lenses. By combining lensing and dynamical analyses we can set firm limits on the dark matter density profile, the controversial inner slope of the dark matter halo, the mass-to-light ratio of the luminous component, the total mass distribution, and on the velocity ellipsoid by breaking the mass anisotropy-relation. The implications of these measurements in terms on the epoch and mechanism of formation of E/S0 galaxies and of the value of the Hubble constant are briefly discussed.

We use the method of statistical parallaxes to construct the rotation curve of the Milky Way spanning the Galactocentric distance interval from 2 to 14 kpc based on observational data for young disk populations and refine the distance scales of the objects belonging to young disk populations (classical Cepheids, young open clusters, blue supergiants, HII regions, and HI).

We obtain ages and metallicities of four open clusters from characteristics of SB2 eclipsing binary members of these clusters. In addition, we present similar estimates obtained with a modification of the color-magnitude diagram method for six open and globular clusters.

A sample of nearly 400 stars, selected from the Tycho-2 catalog, has been observed towards the North Galactic Pole with the high resolution echelle spectrograph Elodie. Combining those data with a local sample from the Hipparcos catalog, a detailed study of the disk components is done. A dynamical analysis is also performed, enabling us to put new constraints on the local mass density.

The impact of rotation on the relaxational dynamics of dense stellar systems is reviewed; while in the past linear stability analysis and a few N-body models existed only, we report recent advances in the technique of 2D Fokker-Planck models for axisymmetric rotating star cluster, now extending into the post-core collapse phase. It is confirmed that rotating clusters, whether they are in a tidal field or not, evolve significantly faster in pre-collapse than non-rotating ones, while in post-collapse only those in a tidal field keep their larger speed of evolution. Consequences for observed shapes, density distribution, and kinematic properties of young and old star clusters are discussed.

A capture scenario of the origin of ω Centauri is studied numerically. We show that the most serious problem of this scenario - how to move a progenitor of ω Cen from a typical dwarf orbit to the current position of ω Cen - can be solve for a nucleated dwarf galaxy with Hernquist density profile.

Recent progress on the structure and dynamics of bulges is reviewed. Those aspects that link galaxy bulges either to oblate spheroids akin to elliptical galaxies or to rapidly-rotating, flattened systems more nearly resembling the products of disk internal transformations, are highlighted. The analysis of surface brightness profiles derived from HST data is reviewed to show that unresolved nuclear components detected by HST have biased the determination of surface brightness profiles obtained from the ground; r1/4 profiles are virtually nonexistent in galaxy bulges. Predictions from accretion N-body models on the shape of surface brightness profiles are discussed. The position of bulges on the Fundamental Plane (FP) of elliptical galaxies is examined to infer clues on bulge population ages and bulge dynamical structure. Kinematic diagnostics on the internal dynamics of bulges are examined. Finally, a new approach to the kinematic analysis of galaxies, based on the use of synthetic spectra of single stellar population models instead of the standard stellar templates, is presented.

We use a Fourier analysis method to study the spiral structure of the disc galaxies in the Frei et al. (1996) sample. We show that m=1 components are more often associated with asymmetries between the two arms of an m=2 spiral than with global lopsidedness of the disc. The power in the m=2 components is correlated with the arm class. The majority of galaxies with arm class 9 or 12 show clear signs of modulation in their spiral arms, suggesting the action of an amplification mechanism like the Swing amplification. Finally we report new detections of underlying large-scale bisymmetric components in flocculent spiral galaxies.

A simple model for the evolution of an isothermal disk has been developed. It combines both the chemical evolution (through the Age-Metallicity Relation) and dynamical evolution (through the age-dispersion relation). Applying this model to a sample of Red Clump Stars from the Tycho-2 catalog, observed with the high resolution echelle spectrograph Elodie at the Observatoire de Haute Provence, we derive the underlying Star Formation History and compare it with local determinations using chromospheric activity survey by Rocha-Pinto et al. (2000b).

We have compiled a new catalogue of open clusters in the Galaxy which updates the previous catalogues of Lyngå (1987) and of Mermilliod (1995) (included in the WEBDA database). New objects and new data, in particular, data on kinematics (proper motions, radial velocities) that were not present in the old catalogues, have been included. Virtually all the clusters (1622) presently known were included, which represents an increment of about 450 objects relative to the Lyngå (1987) catalogue. The catalogue is presented in a single table containing all the important data (positions, reddenings, distances, ages, kinematics) which makes it easy to use. The catalogue includes mean absolute proper motions for hundreds of open clusters (Dias et al. 2001, 2002a) obtained using the Tycho2 proper motions. Unpublished mean radial velocities of several dozens of clusters are also presented in this work. The catalogue is being constantly updated and the latest version can be accessed on-line at http://www.astro.iag.usp.br/~wilton/ were more data such as membership probabilities for individual stars can also be accessed.