We discuss and illustrate contributions that optical interferometry has made on our current understanding of cool evolved stars. We include red giant branch (RGB) stars, asymptotic giant branch (AGB) stars, and red supergiants (RSGs). Studies using optical interferometry from visual to mid-infrared wavelengths have greatly increased our knowledge of their atmospheres, extended molecular shells, dust formation, and winds. These processes and the morphology of the circumstellar environment are important for the further evolution of these stars toward planetary nebulae (PNe) and core-collapse supernovae (SNe), and for the return of material to the interstellar medium.

This contribution discusses the challenges of implementing star formation andstellar feedback processes in galaxy simulations. Insufficient computational power and numerous poorly understoodphysical processes, force simulations to adopt sub-grid models of the interstellar medium. These maycrucially bias results. We advocate for smaller (~ kiloparsec) scale simulations of the interstellar medium to guide the development of sub-grid models in larger simulations. In this vein, I show results on ever increasing scales ranging from ~1 h-1 kpc3 ISM simulations, to a 1 h-1 Mpc3 simulation of a galaxy forming at high redshift, to a larger cosmological volume, 6.25 h-1 Mpc3, evolved down to redshift 3. We find that galactic winds can be poweredby SN implemented as point explosions in high redshift galaxiessimulated with sufficient spatial resolution. Galaxies at lower redshift require alternative sub-grid feedback models and we present one possible solution to generate winds from galaxies atredshift ~4.



All stars end through a phase where they form copious amounts of dust either in a stellar outflow or following explosive events. The most efficient dust factories seem to be stars that evolve through the Red Giant stage and form for several 105 yrs, dust in a cool stellar wind. The dust returned by them triggers the interstellar dust cycle and therefore is vital for the matter cycling in space. We discuss the theoretical basis for calculating the dust production by such stars. First, some elements of the theory of chemical equilibrium condensation calculations are presented and it is then discussed how the concept of activities can be used to also study non-equilibrium condensation. Then we discuss how dust particle growth in stellar winds can be calculated and which kind of input data are required for such calculations. Finally some results for dust production by AGB stars are discussed.

The Square Kilometre Array is a global project to develop the nextgeneration radio telescope at metre to centimetre wavelengths. It willhave a collecting area of order one million square metres, asensitivity 100 times higher than the extended VLA, an instantaneousfield of view (FOV) larger than the full moon, and, in some designs,more than one FOV allowing multiple simultaneous use. It will be anextremely powerful survey telescope with the capability to follow upindividual objects with high angular and time resolution. The SKA willreach a point source sensitivity of 25 nano-Jy in 1 hour ofintegration, and a maximum resolution of better than 1 milli-arcsecond at20 GHz with excellent imaging over several orders of magnitude at anygiven frequency. The SKA science reach will be enormous, allowing newdiscoveries in astroparticle physics and cosmology, fundamentalphysics, galactic and extragalactic astronomy, and solar systemscience. Technological innovation, closely paralleling commercial ITdevelopments, is key to the design concepts under investigation and tothe cost goal of USD 1000/m2. The selection of technologies for theSKA is scheduled in early 2008. A number of possible locations for thetelescope are under investigation with a choice scheduled in early2006. Construction of the array will take most of the next decade.


This paper reviews the various processes that have been proposed to explain the observedtrend of PAH strength with metallicity. It summarizes a study showing that, although PAHdestruction by hard radiation is important in low-metallicity environments, it is notsufficient to explain their paucity. In these systems, the deficiency of their formationmechanism, related to stellar evolution, has to be invoked.

Classification and parametrization of unresolved galaxies to be detected by Gaia is thegoal of our contribution to DPAC/CU8. Gaia will observe more than several times106 unresolved galaxies seen almost as point sources. For the classificationand parametrization of these sources we have undertaken the following tasks: a) providinglibraries of synthetic galaxy spectra (produced under the PÉGASE.2 code of galaxyevolution) and a semi-empirical library using observed galaxy spectra from SDSS dataarchive. b) Developping an appropriate algorithm called Unresolved Galaxy Classifier(UGC). The algorithm is being developed implementing the Support Vector Machines (SVM), asupervised training technique. This algorithm utilizes Gaia simulated BP/RP galaxy spectraof our synthetic galaxy library.

We apply a simple, one-equation, galaxy formation model on top of the halos and subhalos of a high-resolution dark matter cosmological simulation to study how dwarf galaxies acquire their mass and, for better mass resolution, on over 105 halo merger trees, to predict when they form their stars. With the first approach, we show that the large majority of galaxies within group- and cluster-mass halos have acquired the bulk of their stellar mass through gas accretion and not via galaxy mergers. We deduce that most dwarf ellipticals are not built up by galaxy mergers. With the second approach, we constrain the star formation histories of dwarfs by requiring that star formation must occur within halos of a minimum circular velocity set by the evolution of the temperature of the IGM, starting before the epoch of reionization. We qualitatively reproduce the downsizing trend of greater ages at greater masses and predict an upsizing trend of greater ages as one proceeds to masses lower than mcrit. We find that the fraction of galaxies with very young stellar populations (more than half the mass formed within the last 1.5 Gyr) is a function of present-day mass in stars and cold gas, which peaks at 0.5% at mcrit = 106−8 M⊙, corresponding to blue compact dwarfs such as I Zw 18.

Dome Fuji is potentially one of the best astronomical sites in Antarctic plateau. We have a plan to build a 2-m class infrared telescope at Dome Fuji, and have been evaluating the site since the 2006/2007 Antarctic summer. We present the outline of a 2-m class telescope project and some results of our SODAR measurements.

The evolution of stars in the mass range 7–12 M๏ is characterized bythe off-center ignition of carbon in condition of partially degeneracyfollowed by the propagation of a convectively bound flame and the formationof a neon-oxygen core. In this chapter, we review the evolutionaryfeatures of these peculiar stars and pay a special attention to thethermally pulsing super-AGB phase and associated nucleosynthesis. Theevolution toward electron capture supernovae for the most massive membersof this class is briefly mentioned. In light of new computations, we alsodiscuss the question of Mup, the critical mass above which carbon ignitesas well as Mn, the minimum mass for the formation of a neutron star andanalyze the dependence of these transition masses on metallicity.

We present a summary of the extensive problems posed by the curious abundance correlations seen in stars in Galactic globular clusters.We discuss three scenarios, and conclude that only one seems to beconsistent with the observations. Even this is still rather unsatisfyingfrom many viewpoints. We determine the kind of nucleosynthesis requiredand discuss AGB stars as the possible source. Some calculations seem torule out AGB stars and others seem to favour them. The reasons for the differences are discussed. No satisfying conclusion is reached!

Seismology is the only way to investigate the internal structure ofthe giant planets, with a lot of scientific implications such ashigh pressure physics and huge constraints on the scenario of solarsystem formation. As compared to other existing possibilities(ground based network, spacecraft), seismology of Jupiter will takea maximum benefit from the peculiarities of the Concordia station asan astronomical observatory. Indeed, the continuous temporalcoverage for all the winter season, and the quality of theatmospheric seeing, are crucial parameters for this program. Thejovian seismometer SYMPA, already used for network observations, isperfectly suitable for Dome C conditions. With the alreadyexisting small telescopes deployed in the frame of site testingprogram, seismology of Jupiter will constitute a excellentintermediate project with high scientific return, before theinstallation of large telescopes. In a second step, such aninstrument could be a first light instrument for a 1.5 m classautomatic telescope, which is to be developed as an individual stonefor a large interferometer. With this diameter, the same scientificprogram on Saturn could also be achieved.

We discuss recent progress made in the spectral modelling of OB stars from the main sequence to evolved phases as BA-type supergiants. Non-LTE line-formation computations can now reproduce observed spectra over the entire optical and near-IR wavelength range with high confidence, facilitating stellar atmospheric parameters and elemental abundances to be determined at high accuracy and precision. An overview is given how the fundamental stellar parameters of single stars determined in our new approach compare to high-precision data derived from detached eclipsing massive binary stars. Finally, the observational constraints for a sample of Galactic objects are put in context with state-of-the-art evolution models for rotating massive stars.

We have found low-mass star-forming regions with extremely high abundances of carbon-chain molecules. Those are L1527 in Taurus and IRAS 15398-3359 in Lupus. In these sources, carbon-chain molecules would be regenerated in a lukewarm region near the protostar, triggered by the evaporation of the CH4 ice. This is new carbon-chain chemistry (Warm Carbon-Chain Chemistry: WCCC) in contrast to the conventional one applied to cold starless cores. Our interferometric observation shows a steep abundance increase of the carbon-chain molecules inward of a radius of 500 − 1000 AU from the protostar. This size corresponds to the temperature range of 20–30 K, which is close to the evaporation temperature of CH4 (25 K). This result is therefore consistent with the WCCC. The discovery of the WCCC sources demonstrates chemical diversity of low-mass star-forming regions. In particular, a remarkable contrast can be seen between the WCCC and the hot corino chemistry known in IRAS 16293-2422. A possible origin for the diversity would be the time scale of the starless-core phase; a shorter contraction time would result in the WCCC. Relatively low deuterium fractionation ratios in L1527 also support this scenario. If so, chemical compositions will tell us an important clue to understand the source-to-source variation of star-formation processes.

The accretion and desorption processes of gas molecules on cold grains play an important role in the evolution of dense clouds and circumstellar regions around YSOs. Given the low temperatures in dark cloud interiors (10–20 K), thermal desorption is negligible and most molecules are expected to stick to grains leading to depletion in the gas phase. Laboratory simulations of these processes under astrophysically relevant conditions are required for their understanding. The use of ultra-high-vacuum conditions minimalizes contamination by background water accretion. This introduces a radical improvement, allowing the study of photodesorption and the detection of products at very low abundances in a water-free ice matrix. We studied UV-photoprocessing of pure NH3 and N2 ices under ultra-high-vacuum conditions using the Interstellar Astrochemistry Chamber. The photodesorbed molecules, and the volatile products released upon photolysis and warm-up, were detected in situ by quadrupole mass spectroscopy.

Surveys provide a wealth of data to the astronomical community that are used well after their completion. In this paper, we propose a project that would take the maximum benefit of Dome C in Antarctica by performing two surveys, in the wavelength range from 1–5 µm, complementary to SNAP space surveys. The first one over 1000 sq. deg. (1 KdF) for 4 years and the second one over 15 sq. deg (SNAP-IR) for the next 4 years at the same time as SNAP 0.35–1.7 µm survey. By using a Ground-Layer Adaptive Optics system, we would be able to recover, at the ice level and over at least half a degree in radius, the ~300 mas angular resolution available above the 30-m high turbulent layer. Such a survey, combining a high angular resolution with high sensitivities in the NIR and MIR, should also play the role of a pre-survey for JWST and ALMA.

The infrared fluorescence decay and the dispersed emission spectrum are presented for gaseous benzene following 193 nm laser excitation. They were measured with FIREFLY (Fluorescence in the InfraRed from Excited FLYing molecules), a new home-made spectrometer. Redshift and redtail in the CH stretch emission spectra (3.3 μm region) demonstrate that anharmonicity plays a key role when dealing with high internal energies, as it is the case in the interstellar medium.

We investigated the dependence of a spectral lag against energy band based on 28 brightGRBs registered by SPI and IBIS/ISGRI of INTEGRAL observatory. It was found that forsimple structure bursts or well separated pulses of multipulse bursts the spectral lag canbe approximated by the relation ofτ ~ Alg(E), where A is a positiveparameter, which correlates with pulse duration. We have not found any negative lag insimple structure bursts or in well separated pulses. While investigating the time profileof the whole burst negative lag may appear due to different spectral parameters of thepulses.

Accurate characterization of the errors in the global astrometric solution for Gaia isessential for making optimal use of the catalogue data. We investigate the structure ofthe covariance between the estimated astrometric parameters by studying the properties ofthe astrometric least squares solution. We find that astrometric errors can be separatedin a star and an attitude part, due to the estimation of the star and attitude parametersrespectively. Hence the covariances can be separated in a star, an attitude and a crossterm. This is demonstrated using our scalable simulation tool AGISLab, where thecovariances are estimated statistically using Monte Carlo techniques.

There is an ongoing debate in the literature concerning the effects of averaging out inhomogeneities (“backreaction”) in cosmology. In particular, some simple models of structure formation studied in the literature seem to indicate that the backreaction can play a significant role at late times, and it has also been suggested that the standard perturbed FLRW framework is no longer a good approximation during structure formation, when the density contrast becomes nonlinear. In this work we use Zalaletdinov's covariant averaging scheme (macroscopic gravity or MG) to show that as long as the metric of the Universe can be described by the perturbed FLRW form, the corrections due to averaging remain negligibly small. Further, using a fully relativistic and reasonably generic model of pressureless spherical collapse, we show that as long as matter velocities remain small (which is true in our model), the perturbed FLRW form of the metric can be explicitly recovered. Together, these results imply that the backreaction remains small even during nonlinear structure formation, and we confirm this within the toy model with a numerical calculation.

Solar magnetic fields are produced by dynamo action in or just below the solar convection zone. After an account of observations of solar magnetic activity, the fundamentals of dynamo theory are reviewed, and the ideas applied to a discussion of different models of dynamo action in the Sun.