In the quest for a better theoretical understanding of the dynamical processes operating in stellar envelopes, increasingly more realistic hydrodynamical models of stellar convection have been developed over the last 25 years. Based on 3D state-of-the-art simulations performed recently with the radiation hydrodynamics code CO5BOLD, we review the present status of hydrodynamical modeling of stellar surface convection and demonstrate the basic differences between 3D hydrodynamical models and 1D ‘classical’ hydrostatic atmospheres where convection is treated by the mixing-length theory. We briefly discuss some of the many possible applications across the Hertzsprung-Russell diagram, including spectroscopic abundance determinations using 3D stellar atmospheres, particularly with regard to the much debated question of the solar oxygen abundance.

In this poster contribution, we present results from high spatial resolution integral-field spectroscopy of elliptical (E) and lenticular (S0) galaxies from the SAURON representative survey, obtained with the OASIS and GMOS spectrographs. These seeing-limited observations explore the central ∼10''10″ (typically one kiloparsec diameter) regions of these galaxies using a spatial sampling four times higher than SAURON (0″27 vs. 0″94 spatial elements), resulting in almost a factor of two improvement in the median PSF. These data allow accurate study of the central regions to complement the large-scale view provided by SAURON. We derive the stellar and gas kinematics, stellar absorption-line strengths and nebular emission-line strengths for our sample, and derive maps of the luminosity-weighted stellar age, metallicity and abundance ratio via stellar population models. From these data we find a wealth of structures either not seen or poorly resolved in the SAURON data, including a number of kinematically-decoupled cores (KDCs) in the centres of some galaxies. We compare the intrinsic size and luminosity-weighted stellar age of all the visible KDCs in the full SAURON sample, and find two types of components: kiloparsec-scale KDCs, which are older than 8 Gyr, and are found in galaxies with little net rotation; and compact KDCs, which have intrinsic diameters of less than a few hundred parsec, show a range of stellar ages from 0.5 - 15 Gyr (with 5/6 younger than 5 Gyr), are found exclusively in fast-rotating galaxies, and are close to counter-rotating around the same axis as their host. Of the 7 galaxies in the SAURON sample with integrated luminosity-weighted ages less than 5 Gyr, 5 show such compact KDCs, suggesting a link between counter-rotation and recent star-formation. We show that this may be partly due to a combination of small sample size at young ages, and an observational bias, since young KDCs are easier to detect than their older and/or co-rot ating counterparts.

Many astrophysical problems, ranging from structure formation in cosmology to dynamics of elliptical galaxies, refer to slow processes of evolution of essentially collisionless self-gravitating systems. To determine the relevant quasi-equilibrium configuration at time t from given initial conditions, such slow evolution is often approximated in terms of adiabatic evolution. Here we focus on the slow process of evolution induced by dynamical friction of a spherical stellar system (the host galaxy) on a minority component of “satellites” (distributed in a spherical shell), to determine to what extent an adiabatic description might be applied.

Studies of molecular clouds have shown that they evolve from turbulent gas and dust to form coherent, dense and connected structures. We have conducted a multi-wavelength study of one such molecular cloud, the Perseus star-forming region, which includes Barnard 1 (B1), Barnard 3(B3), Barnard 5 (B5), NGC 1333, IC 348, L1455 and L1448. The data obtained using the Infrared Array Camera (IRAC), Multiple Imaging Photometer (MIPS), the Sub-mm Common User Bolometer Array(SCUBA) and the 2 Micron All Sky Survey (2MASS)provides information about the geometric structure of the dust and gas covering large areas around young stellar objects (YSO), dust temperatures, effect of turbulence and processes of molecule formation and their relevance in the chemical and physical evolution of the cloud. This paper presents our first results.

Theory predicts the triggered formation of molecular clouds stars through the fragmentation and collapse of swept-up ambient gas. Yet the majority of Galactic HI shells show no more than a scattering of small molecular clouds. The Carina Flare supershell (Fukui et al. 1999) is a rare example of an HI shell with a striking molecular component. Here we present the large-scale morphology of the molecular and atomic gas and the location of YSO candidates. A detailed look at two molecular clumps in the shell walls reveals active, intermediate mass star forming regions at various stages of early evolution.

We present the first results from a project to map Giant Molecular Clouds (GMCs) in the 12CO J=2-1, 13CO J=2-1, and 12CO J=3-2 lines using the Heinrich Hertz Submillimeter Telescope (HHT) at the University of Arizona. We mapped nearly 2.5 sq. deg of W3 and 1.0 sq. deg of W51 in the J=2-1 lines. We have begun mapping in the J=3-2 line. We achieve angular resolutions of 33″ and 24″ in the J=2-1 and J=3-2 lines with 1.3 and 0.9 km s−1 resolution.

The International Astronomical Union has a strong commitment to the development of astronomical education and research throughout the world, especially in those countries developing economically. This commitment is in part through the work of IAU Commission 46 for astronomy education and development. Within that commission, the Program Group for the World-wide Development of Astronomy (PGWWDA) coordinates many of these activities, promoting the development of astronomy in developing countries.

This is an ongoing project.

During last few years, new instruments like GIRAFFE (Flores, H., Hammer, F., Puech, M., et al., 2006, A&A 455,107) or SINFONI (Förster Schreiber, N.M., Genzel, R., Lehnert, M.D., et al., 2006, ApJ 645,1062) have began investigations on 3D kinematics of high redshift galaxies. This is just the head of the iceberg as Extremely Large Telescope will allow this kind of study on a larger sample. By now, it is important to be able to recover the actual kinematic parameters, and overall to disentangle evolutionnary effects from distance effects.

The status of Japan's planning of the optical/infrared astronomy projects for the 2010's is briefly reviewed. The road map shows a 30 m class extremely large ground based telescope project with advanced adaptive optics capability, JELT, and a mid-infrared optimized 3.5 m space telescope project, SPICA, as the top-priority major project to be accomplished probably on international collaboration basis.

We study the inclination dependent luminosity function (LF) of spiral galaxies of the Sloan Digital Sky Survey (SDSS). Up to 60000 sample galaxies are selected from the 2nd data release of SDSS by fracdeVr < 0.5. Magnitudes and other related photometric parameters are taken from NYU-VAGC(Blanton et al.2005). The apparent axis ratio (b/a)is used as an observational inclination indicator to define sub-samples. LFs of all 5 SDSS bands (u, g, r, i, z) are drawn for different sub-samples. Significant correlation is found between characteristic magnitudes (M*) of sub-samples and their inclinations, which can be fairly explained by dust extinction. A linear fit of the relation between M* and log(b/a) measures the M*(0) (for expected face-on spirals, with 0.2 ~ 0.3 mag brighter than that of LF of whole sample) and the intensity of dust extinction γ, for each band (Figure 1(a)). Additionally, since γ ∝ τ (optical depth), the wavelength dependent γ describes the extinction curve. Figure 1(b) shows a good linear fit that implies the extinction curve obeys the power law very well, with τλ = τV(λ/5500Å)−0.97±0.07. The power index n ~ 1 is shallower than that of the MW, LMC and SMC (n=1.1~1.5), but significantly steeper than the value of Charlot et al. (2000) (n=0.7), which under the assumption of a patchy distribution of dust in spiral galaxies. So our result implies that dust distributed in spirals, on average, are not as patchy as Charlot et al. assumed.

Globular clusters have been long predicted to host intermediate-mass black holes (IMBHs) in their centres. The growing evidence that some/all Galactic globular clusters (GCs) could harbour middle range (102 – 104M⊙) black holes, just as galaxies do, stimulates the searches and the development of new methods for proving their existence. Here we propose another method of detection – the microlensing of the cluster stars by the central BH.

New observations in favour of a significant role of secular evolution are reviewed: central star formation boosted in pseudo-bulge barred galaxies, relations between bulge and disk, evidence for rejuvenated bulges. Numerical simulations have shown that secular evolution can occur through a cycle of bar formation and destruction, in which the gas plays a major role. Since bars are weakened or destroyed in gaseous disks, the high frequency of bars observed today requires external cold gas accretion, to replenish the disk and allow a new bar formation. The rate of gas accretion from external filaments is compatible with what is observed in cosmological simulations.

The Square Kilometre Array SKA is intended to be the centimeter- and meter-wavelength telescope for the 21st century. At long wavelengths, the SKA's key science projects include the search for highly redshifted hydrogen, including the signal from the epoch of re-ionization, and the search for the first supermassive black holes.

Results of the Genesis mission to sample the solar wind are summarized.

The particle reaceleration model is one of the most promising possibilities to explain the Mpc-scale diffuse radio emission detected in a number of galaxy clusters. Ongoing and future radio observations at low frequencies may help in constraining and testing this model.

We study the star formation history of the galactic young open cluster NGC 6231 using new, deep, wide-field BVRI imaging. Contrary to previous suggestions, we do not find a lack of low-mass cluster members; our derived mass function is compatible with a Salpeter IMF. The star formation history of NGC 6231 appears to be bi-modal, with a first wave of star formation activity 3–5 Myr ago, followed by a new generation of stars forming ~ 1 Myr ago.

We discuss the issue of selecting highly-compact radio sources for the definition of the celestial reference frame.

The Virtual Observatory provides a natural solution to the existence problem in communications: how can one ask a question of another unless you know the other exists? Many think e-mail from apparent strangers, e-blogs, etc., suggest there is no shortage of possible such solutions. In that context, is the Virtual Observatory in fact the necessary and desirable part of the solution? Specifically, does the VO necessarily play a critical role in delivering end-to-end facility science, from ideas, through proposals, resources/facilities, to distributed, reviewed, knowledge? If not, what else needs to be added?

Different hydrodynamic regimes for the gaseous outflows generated by multiple supernovae explosions and stellar winds occurring within compact and massive star clusters are discussed. It is shown that there exists the threshold energy that separates clusters whose outflows evolve in the quasi-adiabatic or radiative regime from those within which catastrophic cooling and a positive feedback star-forming mode sets in. The role of the surrounding ISM and the observational appearance of the star cluster winds evolving in different hydrodynamic regimes are also discussed.

By using 2D simulations, we examine the generation of dense cores and substructures by magnetosonic waves. We find that the excitation of slow-mode waves by fast-mode waves produces these high-density structures.