Optical Interferometry has had an impressive 30-year run of innovation, prototyping and implementation. Some half-dozen arrays are now in operation. Publications are increasing exponentially. In a future phase of advanced facility development, interferometry could move in any of several directions: increased sensitivity, higher resolution, better imaging. What role may the Antarctic have in the future?

While the PAMELA collaboration has recently confirmed the cosmic ray positron excess, it is interesting to review the effects of dark matter subhalos on the predicted antimatter signals. We recall that, according to the general subhalo properties as inferred from theoretical cosmology, the enhancement cannot be larger than ~20 for the antimatter yield. This bound is obviously different from what is found for γ-rays. We also show some predictions for supersymmetric benchmark models observable at the LHC and derived in the cosmological N-body framework, but remind the existing discrepancy between the profiles derived from N-body experiments and the current observations.

The search for extrasolar transiting planets requires high accuracy photometric observations over a long time basis. The method therefore favors observing sites allowing for long uninterrupted observations, or observations with space satellites. The first space mission searching for planetary transits is the French-led CoRoT mission launched in December 2006. Its longest observing sequences span 150 days, whereas Dome C can provide a ground-based site for observations over 2–3 months. Full observational coverage of at least three transit events up to about two weeks orbital period can be obtained from Dome C during one winter season when realistic conditions for cloud coverage are taken into account. The efficiency can be further optimized if Dome C is combined with other sites at low-latitudes, closing the gap of the summer break in Antarctica.


Telescope pupils are usually not well suited for high dynamical range imaging. Central obstruction, telescope spiders, hard edges and sparseness (for interferometers) can make it very challenging to build a coronagraph. Fortunately, it is often possible to remap a telescope pupil to achieve high contrast imaging without loosing light. In the case of a monolithic telescope, pupil remapping can produce an apodized pupil with 2 aspheric mirrors which redistribute the light without introducing phase aberrations. Similarly, an interferometer pupil can be remapped into a tight configuration compatible with coronagraphic techniques.

In this paper we give a survey of the methods we have developed for multiple image deconvolution, with application to the reconstruction of the images of the Large Binocular Telescope (LBT). We first describe the main features of LBT and of the Fizeau interferometer, denoted LINC-NIRVANA, that will be one of the basic instruments of the telescope. It will allow to reach the resolution of a 22.8 m mirror by combining different images taken with different orientations of the baseline. Next we discuss the problem of multiple image deconvolution, that is crucial for obtaining a unique high-resolution image from the multiple images provided by LINC-NIRVANA. We present the state-of-the art of the methods based on the Richardson-Lucy (RL) approach and we discuss topics such as computational efficiency, correction of boundary effects and super-resolution. Then, in the perspective of going beyond RL, we extend to the problem ofmultiple image deconvolution the split gradient method (SGM) that isa general approach to the design of iterative methods for the constrained minimization of regularized functionals. Finally we present an application of SGM to the regularized reconstruction of objects with high-dynamic range. The different methods are illustrated with examples taken from the many numerical experiments we performed on this problem.

The Herschel Dwarf Galaxy Survey investigates the metal enrichment of the dust and gas in galaxies through observations of the local universe dwarf galaxies via the new far-infrared (FIR) and submillimetre imaging spectroscopic and photometric observations from the recently launched Herschel Space Observatory. The dust spectral energy distributions can now be constrained out to submm wavelengths and often show a submm excess in the low metallicity galaxies, which, if tracing very cold dust, could highlight large dust masses, sometimes not easily reconciled with their low-metallicity and observed gas mass. Additionally, Herschel observations of the FIR fine-structure lines probe the low density ionised gas, the HII regions and photodissociation regions. L[CII]/LCO is remarkably high in dwarf galaxies – typically an order of magnitude larger than more metal-rich starburst galaxies, pointing to a potentially significant reservoir of H2 not traced by CO but shielded in the C+-emitting envelopes. Thus a more accurate estimate of the molecular gas mass in low metallicity galaxies will be via the (CO + [CII]) to H2 conversion factor. The 88 μm [OIII] line is the brightest of all FIR lines in low-metallicity galaxies, sometimes 1.5 to 2 time brighter than the 158 μm [CII] line which is usually the dominate FIR coolant in normal spiral and starburst galaxies. The 88 μm [OIII] line may become the workhorse diagnostic for the high-redshift low-metallicity galaxies which will be targets for future submm observatories, such as ALMA. Further observations from The Herschel Dwarf Galaxy survey will provide a more complete picture of the nature of the dust and gas in low metallicity galaxies and thus a more comprehensive view of the chemical evolution of galaxies.

Red supergiants with their enormous brightness at J-band are ideal probes of cosmic chemical composition. It is therefore crucial to have realistic models of radiative transfer in their atmospheres, which will permit determination of abundances accurate to 0.15 dex, the precision attainable with future telescope facilities in galaxies as distant as tens of Mpc. Here, we study the effects of non-local thermodynamic equilibrium (NLTE) on the formation of iron, titanium, and silicon lines, which dominate J-band spectra of red supergiants. It is shown that the NLTE radiative transfer models enable accurate derivation of metallicity and effective temperature in the J-band. We also discuss consequences for RSG spectrum synthesis in different spectral windows, including the heavily TiO-blanketed optical region, and atmospheric structure. We then touch upon challenges of NLTE integration with new generation of 3D hydrodynamical RSG models and present the first calculations of NLTE spectra with the mean 3D model of Betelgeuse.

CASPER (Concordia Atmospheric SPectroscopy of Emitted Radiation)is a spectrometer proposed for installation at Dome C, devoted tomeasurements of atmospheric emission in the spectral regionbetween 180 μm and 3 mm (3–55 cm-1). Thisinstrument will be able to perform continuous spectral sampling atdifferent altitudes at angular scales of ~1°. From therecorded data it is possible to extract atmospheric transmittancewithin 1% in the whole wide operating band, together with watervapour content and O2 and O3 concentrations. CASPER willallow us to characterize the site for future FIR/mm telescopes.Atmospheric data recorded by CASPER will allow for correction ofastrophysical and cosmological observations without the need fortelescope-specific procedures and further loss of observation timewith more precision in the observations themselves. Calibration ofground-based telescopes on known sky sources is strongly affectedby atmospheric absorption. CASPER has this as its primary goal.The spectrometer is based on a Martin-Puplett interferometer. Twodata sampling solutions will be performed: phase modulation &fast scan strategy. Sky radiation is collected towards theinterferometer by an optical setup that allows the field of view,to explore the full 0° ÷ 90° range of elevation angles. Witha low spurious polarization instrument, monitoring of polarizedatmospheric contribution will be possible.

Nebular emission lines are easy to observe, and their spectrum contains a lot of information. We explain the mechanisms of production of the emissions, and the relation between the intensity of the recombination and forbidden lines, and the physical parameters of the objects. A gallery of emission lines spectra is presented, and a rough analysis will clarify their differences. The case of Planetary Nebulae will be developed, in order to determine the extinction constant, the plasma parameters (electron density and temperature), the chemical abundances, and also the properties of the central star (temperature, mass, stellar wind velocity, age).

We describe recently proposed algorithms, denoted scaled gradient projection (SGP) methods, which provide efficient and accurate reconstructions of astronomical images. We restrict the presentation to the case of data affected by Poisson noise and of nonnegative solutions; both maximum likelihood and Bayesian approaches are considered. Numerical results are presented for discussing the practical behaviour of the SGP methods.

Atomic diffusion – important in many contexts in stellar astrophysics and an important thread running through this meeting – is most spectacularly observable in the atmospheres of some A stars. The magnetic Ap stars and the non-magnetic Am stars show directly abundance anomalies caused by gravitational settling and radiative levitation. Over the last decade spectroscopic studies have begun to provide maps of abundance distributions in the magnetic Ap stars in three dimensions. Interestingly, high radial overtone p-mode pulsations in roAp stars have also given three-dimensional views of the stellar atmospheres with studies of rotational and line profile variations of pulsation amplitudes and phases. These detailed looks at the effects of microscopic atmospheric changes in the strongly non-LTE and magnetic upper atmospheric layers of Ap stars provide perhaps the most exciting challenge to atomic diffusion theory in terms of detailed explanation and prediction. Am stars were at one time thought not to pulsate because of gravitational settling of He from the He ii ionization zone that provides the κ-mechanism driving for δ Sct pulsations in A stars. In the last few years we have found with SuperWASP and Kepler observations that many Am stars do pulsate. More than half of all A stars pulsate at Kepler micromagnitude precision, yet there is a subset of A stars that truly do not pulsate at that level. Are these Am stars with the strongest signature of atomic diffusion? Is atomic diffusion the reason for the pulsational stability of these stars? The answers are not yet known.

Over the last few years, evidence that nearby spiral galaxies are surrounded by massive halos of cold gas has been accumulating. This extra-planar cold gas, rotating more slowly than the disk gas, is observed in galaxies with a range of different properties (such as mass and star formation rate, SFR) and it appears analogous to the Intermediate and High Velocity Clouds of the Milky Way. Models for the origin of extra-planar gas have been proposed taking into account the effects of supernova feedback (galactic fountain), cooling flow accretion and hydrostatic equilibrium. Several techniques have been used from analytical treatments and ballistic orbit integration to hydrodynamical simulations. I present a new model where a galactic fountain sweeps up ambient medium as it travels through the halo. This seems to give the best results in reproducing the kinematics of the extra-planar gas and it implies a gas accretion rate of the order of the SFR of the host galaxy.

The AMANDE facility produces mono-energetic neutron fields from 2 keV to 20 MeV with a metrological quality (Gressier et al. 2004). To be considered as a standard facility, fluence and energy distributions of neutron fields have to be mastered, i.e. measured by primary detector standards. For this purpose, a new gaseous Time Projection Chamber (μTPC) is being developed within the MIMAC project devoted to directional Dark Matter search (Billard et al. 2010). The μTPC is dedicated to measure neutron fields from 2 keV up to 1 MeV. The measurement strategy requires track reconstruction of recoiling nuclei down to a few keV, which can be achieved with low pressure gaseous detectors. Hence the energy must be measured precisely and the track of the recoiling nucleus must be 3D reconstructed. This is achieved with a low pressure micropattern gaseous detector (a pixelized bulk micromegas) equipped with a self triggered electronics able to perform the anode sampling at a 50 MHz frequency. Methods to measure fluence and neutron energy with the TPC have been described.

Supernovae are known to be the dominant energy source for driving turbulence in the interstellar medium. Yet, their effect on magnetic field amplification in spiral galaxies is still poorly understood. Analytical models based on the uncorrelated-ensemble approach predicted that any created field will be expelled from the disk before a significant amplification can occur. By means of direct simulations of supernova-driven turbulence, we demonstrate that this is not the case. Accounting for vertical stratification and galactic differential rotation, we find an exponential amplification of the mean field on timescales of 100 Myr. We highlight the importance of rotation in the generation of helicity by showing that a similar mechanism based on Cartesian shear does not lead to a sustained amplification of the mean magnetic field.

The NIR Ca II triplet has proven to be an important tool for quantitative spectroscopy. Here we present results of synthetic spectral analysis for the Ca II triplet for low-metallicity red giant stars, combined with observational data. Our results start to deviate strongly from the widely-used and linear empirical calibrations below [Fe/H] = −2. We provide a new calibration for Ca II triplet studies which is valid down until [Fe/H] = −4 and apply this new calibration to current data sets. We suggest that the classical dwarf galaxies are not so devoid of extremely low-metallicity stars as was previously thought and discuss preliminary results and possibilities for follow-up observations of these extremely low-metallicity candidates.

Three topics within GAIA photometry have been selected for discussionhere. (1) The sampling scheme of the CCDs has been tuned to serve thevarious purposes: detection of stars, astrometry, broad- andmedium-band photometry, and imaging of a small area around eachdetected star, but the tuning may not yet be optimal. (2) Thecalibration of CCD sensitivity is critical since we aim formillimagnitude accuracy, the spikes of the diffraction image aresuited for an accurate calibration of the magnitude scale, and forextending the range of astrometry and photometry to very bright stars.(3) Finally the various photometric filter systems are illustrated.

The Sun's magnetic activity has changed considerably during its evolution from a protostar to a low-activity main-sequence star. The youngSun produced orders of magnitude more hot plasma, X-ray emission, and high-energyparticles. The present paper summarizes a few recent investigations onthe nature of the magnetic activity and associated high-energy processesin the Sun at different stages of its evolution,with emphasis on the physical mechanisms that may be responsible for coronal heating,the large-scale structure of the magnetic fields, and the possible mass-loss history ofthe Sun.

An invariant classification scheme of algebraicallygeneral rotating dust with a purely electric Weyl tensor ispresented. It turns out that the vorticity vector of the dustcongruence is necessarily parallel to a Weyl principal vector, whichis moreover geodesic. An explicit metric expression can be obtainedfor the subclass of expanding models with one functionallyindependent zero-order Riemann invariant. The basic equations forthe general case, where there are two such invariants, are givenwithin a weighted 1+1+2 tetrad formalism.

Gaia will also provide a comprehensive survey of Solar System objects. If compared toother large ground-based surveys, Gaia potential for discoveries of small asteroidsappears to be limited by its magnitude threshold for detection. However, it can providevaluable data on the physical properties of the observed objects. If compared to LSST,Pan-STARRS or other surveys Gaia is complementary and occupies a clearly definedniche on its own.