We are exploring instrumental concepts of Near and Mid InfraRed (NIR, MIR) wide field camera-spectrographs for a 2 m-class telescope at Antarctica. Scientific drivers are star formation and very low mass objects. Both concepts pretend to exploit the unique features of Dome C: superb seeing, low temperature, improved IR transmission and reduced sky background. Two preliminary concepts are presented here. The NIR instrument would cover the wavelength range 0.97–5.0 μm and would be optimized for the K,L and M bands. The MIR instrument would observe in the range 7–30 μm and would be specifically designed to exploit the extended portion of the Q window (20+ μm).

We use cosmological hydrodynamic simulations including galacticfeedback based on observations of local starbursts to find aself-consistent evolutionary model capable of fitting the observationsof the intergalactic metallicity history as traced by C iv betweenz = 6.0 → 1.5. Our main finding is that despite the relativeinvariance in the measurement of Ω(C iv) as well as the columndensity and linewidth distributions over this range, continualfeedback from star formation-driven winds are able to reproduce theobservations, while an early enrichment scenario where a majority ofthe metals are injected into the IGM at z > 6 is disfavored. Theconstancy of the C iv observations results from a rising IGMmetallicity content balanced by a declining C iv ionization fractiondue to a 1) decreasing physical densities, 2) increasing ionizationbackground strength, and 3) metals becoming more shock-heated at lowerredshift. Our models predict that ~20× more metals areinjected into the IGM between z = 6 → 2 than at z > 6. Weshow that the median C iv absorber at z = 2 traces metals injected 1 Gyr earlier indicating that the typical metals traced by C iv areneither from very early times nor from very recent feedback.

Molecules containing one or a few hydrogen atoms and a heavier atom (hydrides) have been predicted to trace FUV radiation. In some chemical models, FUV emission by the central object or protostar of a star forming region greatly enhances some of the hydride abundances. Two massive regions, W3 IRS5 and AFGL 2591, have been observed in hydride lines by HIFI onboard the Herschel Space Observatory. We use published results as well as new observations of CH+ towards W3 IRS5. Molecular column densities are derived from ground state absorption lines, radiative transfer modeling or rotational diagrams. Models assuming no internal FUV are compared with two-dimensional models including FUV irradiation of outflow walls. We confirm that the effect of FUV is clearly noticeable and greatly improves the fit. The most sensitive molecules to FUV irradiation are CH+ and OH+, enhanced in abundance by many orders of magnitude. Modeling in addition also full line radiative transfer, Bruderer et al. (2010b) achieve good agreement of a two-dimensional FUV model with observations of CH+ in AFGL 2591. It is concluded that CH+ and OH+ are good FUV tracers in star-forming regions.

We present results obtained using the magnetic Dartmouth stellar evolution code that address the possibility that magnetic fields are inflating low-mass stars in detached eclipsing binaries. While it seems plausible that magnetic fields are inflating stars with radiative cores, the level of inflation observed among fully convective stars appears too large to be explained by magnetic fields. We provide an alternative explanation, stellar metallicity, and propose observations that can help further constrain stellar models.

IR spectroscopy is the premier tool to study the composition of interstellar dust. Broad absorption and emission bands provide direct identification of the solid compounds present in space and allow measurement of accurate abundances. Systematic studies of large samples of sources allow then inferences on the origin and evolution of dust in space. Overall, the observed infrared spectra of interstellar and circumstellar dust reveals an incredibly rich and varied composition. This chapter briefly reviews the principles of infrared spectroscopy. This is then applied to the composition of circumstellar oxides and minerals and interstellar Polycyclic Aromatic Hydrocarbon molecules.

The IRAIT (International Robotic Antarctic Infrared Telescope) telescope will be the first European infrared telescope operated on the Antarctic Plateau. The main IRAIT Focal Plane Instrument is AMICA (Antarctic Multiband Infrared CAmera), a two-detector instrument designed to operate in the Near- and Mid-infrared (2-28 µm) regions. IRAIT will start operation during the2007–2008 Antarctic campaign, though the instrumentation will reach Antarctica one year before, at the end of 2006. It will offer a unique opportunity to test the science that can be done from Dome C (in this sense it is a precursor for larger facilities as PILOT). We briefly describe the telescope and its auxiliary equipment, and we presentexample of the kind of science that will be feasible with this infrared observatory of moderate size.

To date, over 30 multiple exoplanet systems are known, and 28% of stars with planets show significant evidence of a second companion. I briefly review these 30 systems individually, broadly grouping them into five categories: 1) systems with 3 or more giant (M sin i> 0.2 MJup) planets, 2) systems with two giant planets in mean motion resonance (MMR), 3) systems with two giant planets not in MMR but whose dynamical evolution is affected by planet-planet interactions, 4) highly hierarchical systems, having two giant planets with very large period ratios (>30:1), and 5) systems of “Super-Earths”, containing only planets with (M sin i< 20 M⊕). 
It now appears that eccentricities are not markedly higher among planets in known multiple planet systems, and that planets with M sin i< 1 MJup have lower eccentricities than more massive planets. The distribution of semimajor axes for planets in multi-planet systems does not show the 3-day pile-up or the 1 AU “jump” of the apparently-single planet distribution.

WEAVE, the next-generation spectroscopic facility for the WHT, is being built with Gaia support as a central science case. WEAVE is a π-square degree multi-fibre system capable of deploying either 1000 single-fibre probes, 20 mini-IFUs or a single large IFU, to feed a two-arm bench spectrograph. With two spectral resolution modes, main products in support of Gaia will be 1–2 km s−1 accuracy radial velocities in the range 16 < V < 20, and abundances of individual elements to ∼0.1 dex up to V ∼ 17. WEAVE will be used to carry out massive surveys that exploit Gaia data in topics of Milky Way astronomy and stellar evolution.

A new type of singularity theorem, based on spatial averages of physical quantities, is presented and discussed. Alternatively, the results inform us of when a spacetime can be singularity-free. This theorem provides a decisive observational difference between singular and non-singular, globally hyperbolic, open cosmological models.

The calibration of the Radial Velocity Zero-Point (RVZP) of the Radial VelocitySpectrometer (RVS) will be performed with the help of Radial Velocity (RV) standard starsand asteroids. A full-sky list of RV standard stars candidates has been built for thispurpose within the Development Unit (DU) 640 of the Gaia DPAC Consortium. A ground-basedcampaign of RV observations has been initiated to eliminate unsuitable candidates.Simulations have also been performed in order to estimate in advance the number of RVstandard stars and asteroids crossing the RVS field of view. These standard stars andasteroids will also be very helpful for controlling any harmful effect (especially the CCDradiation damage) on calibration and RVZP during the lifetime of the Gaia project.Kinematic RV are expected to be published at the end of the project for the brighteststars, taking into account gravitational redshift and convective shifts for the linespresent in the RVS spectral wavelength range.

We present the variability processing and analysis that is foreseen for the Gaia mission within Coordination Unit 7 (CU7) of the Gaia Data Processing and Analysis Consortium (DPAC). A top level description of the tasks is given.

Stellar ages have traditionally been used to constrain cosmological models by setting lower limits to the age of the universe. We quickly review the basic cosmological concepts that underpin the derivation of a finite age, and the constraints given by the measure of cosmological parameters at a redshift z ∼ 1000. The most direct way of measuring stellar ages through the abundance of radioactive elements is shown to suffer from systematics in the evaluation of the production ratios, to the extent that the constrains are less stringent that previously thought. The discrepancy between the ages of the oldest stars and the cosmologically inferred age of the universe may well be dominated by systematc effects in the predicted evolution of low-mass stars.

The Antarctic Plateau provides thebest terrestrial astronomical observing conditions across the Mid-InfraRed (MIR) and submillimeter wavebands due to its remarkable atmospheric transparency and stability. The opening of Concordia Station at Dome C is now offering a unique opportunity to the international submm astronomical community to perform ground-breaking astronomical science.To take advantage of these unique conditions, we are proposing the realization of an international Antarctic Submillimeter Observatory (ASO) based on the ALMA antenna prototype, to carry out both continuum and spectral line observations, across the MIR and submm wavebands. The telescope would be able to operate in the MIR using the innermost surface (2-4 m in diameter) of the primary reflector, which would be accurate enough to operateat wavelengths as short as ~5 micron.

Internal waves and tidal interactions constitute powerful mechanisms for angular momentum exchanges in star-planet systems. In this lecture, we review the state of the art of their modelling and we discuss their impact on the evolution of stellar systems. In this context, we first show how internal waves are able to deeply modify the secular transport of angular momentum in stellar interiors in the whole Hertzsprung-Russelll diagram. Then, we show how tidal waves, as well as the related exchanges of angular momentum, strongly depend on the internal structure of stars and planets.

The Concordia station on the Antarctica plateau will open verysoon its winter-over activities. Astronomy is among the toppriorities, because of the unique qualities that are beingdemonstrated step by step by the site testing programmesConcordiastro and Aastino.

We report on new optical emission line observations toward the northern part of the Magellanic Stream. Using the Wisconsin H-Alpha Mapper (WHAM), we have detected Hα emission toward 17 directions spread across 50∘ of the Stream. We find strong variation in the Hα surface brightness with no significant correlation with Magellanic longitude. We compare our data with HI observations and briefly discuss the implications for the physical conditions of the Stream.

In the present review we summarize direct and indirect evidence that the massive close binary frequency is very large. Wethen discuss the binary evolutionary processes and we present a general massive close binary evolutionary scheme. Finally,we highlight the importance of massive close binaries for population number synthesis and the chemical evolution ofgalaxies.

Aromatic carbon, in some form, has been an essential ingredient by and large in allmodels of the extinction curve, since the original proposal to attribute the bump at 217.5nm to “astronomical graphite”. This aromatic carbon is most naturally identified, in up todate models, with a population of Polycyclic Aromatic Hydrocarbons (PAHs), free and/orclustered. In all models, this PAH population accounts for the far–UV nonlinear rise inthe extinction curve, contributes to the bump and possibly part of the large set ofunidentified, discrete absorption features in the visible (the Diffuse InterstellarBands). We review the current state of our understanding of the contribution of PAHs tointerstellar extinction, and what constraints can be imposed on the PAH population byfitting extinction models to observations.

Laboratory studies on the interaction of atomic hydrogen with aliphatic and aromatichydrogenated carbon grains are discussed. When exposed to atomic hydrogen, both types ofhydrogenated carbon grains act as catalysts for molecular hydrogen formation. In the firstcase, an exchange reaction with hydrogen chemisorbed in aliphatic carbon sites is theformation route to H2 formation. For aromatic carbon grains, the formation ofmolecular hydrogen takes place through a two-step reaction sequence: 1) superhydrogenation of the aromatic carbon islands of grains 2) exchange reactions on theseislands. This mechanism represents a good approximation of molecular hydrogen formation onlarge neutral PAHs.

KIDA (for KInetic Database for Astrochemistry) is a project initiated by different communities in order to 1) improve the interaction between astrochemists and physico-chemists and 2) simplify the work of modeling the chemistry of astrophysical environments. KIDA was designed to group at the same place and with the same format all gas-phase chemical reactions useful for astrochemical simulations of the interstellar medium and planetary atmospheres. From KIDA, a subset of chemical reactions has been extracted for the cold and dense interstellar medium: kida.uva.2001.