PILOT (Pathfinder for an International Large OpticalTelescope) isa proposed 2 m class optical/infrared telescope to be sited atDome C on the Antarctic plateau. Recent site testing results fromDome C have shown remarkable ground level seeing, a largeisoplanatic angle, and a long atmospheric coherence time. Thesefactors significantly improve the resolution and increase thecapabilities of adaptive optics systems. Additionally, the low skyemission at Dome C gives a significant increase in infraredsensitivity compared to typical mid-latitude sites. PILOT isenvisaged as a winterised version of a commercially available 2 mclass telescope, with a simple low cost dome (sufficient for thelow ground level wind speeds), and a tip-tilt and/or a deformablesecondary mirror. A number of science cameras covering the visibleto the sub-millimetre are being considered.

The frequency of planets in binaries is an important issue in the field of extrasolar planet studies, because of its relevance in the estimate of the global planet population of our Galaxy and the clues it can give to our understanding of planet formation and evolution. Here we present an update of the results discussed in Bonavita & Desidera (2007) (hereafter BD07), where we reported the outcomes of our literature search for binaries and multiple systems among the sample with uniform detectability (UD) defined by Fischer & Valenti (2005) (hereafter FV05).

The author discusses models of the Milky Way. An interpolation formula for the contribution of the exponential disc to the circular velocity is proposed.

Period analysis of eclipsing binaries can be performed effectively when using fine-tuned phenomenological models. The combination of regression analysis and genetic algorithms is a powerful tool for such astrophysical tasks as light curve analysis, mid-eclipse time determination and O − C diagram investigation – even apsidal motion and light time effect can be resolved.

A very brief introduction to the theory of line broadening is presented.

We explore the possibility that galaxy clusters or halos could besuited environments to host fermions like massive neutrinos in theirdegenerate state. Equilibrium density profiles for galaxy clustersand halos are calculated where the contribution of fermion particlesto an isotropic collisionless component is taken into account.Fermions are supposed to cluster in CDM protoclusters while theirphase space density is sufficient for not neglecting the Pauli'sexclusion principle.


Close hierarchical triple stellar systems offer a unique possibility to study not only theoretically, but even observationally (at least with limitations) the interaction between a non-spherical and temporally variable gravitational field and the internal structures of the stars. From this purpose a new numerical integrator was developed for studying the orbital and spin evolution of hierarchical triple stellar systems. The code includes equilibrium tide approximations with arbitrary direction of rotational axes. The variation of the orbital elements (e.g. the inclination of the close -eclipsing- binary) and its observational consequences according to the distorted models with different mass-distributions of the stars, as well as with and without dissipation, is studied in the case of the well-known eclipsing triple system Algol. We found that in the absence of dissipation the third star may cause sudden fluctuations in the orbital elements and in the rotation of the binary components, even if they were previously synchronized. Tidal dissipation can eliminate these fluctuations; nevertheless certain variations may subsist, and they could explain some effects that have been observed in several eclipsing binaries.

We show that in rapidly oscillating Ap stars with resolvedmagnetically split lines, different pulsation behaviours can beexpected for the π and σ line components. We outline theprospects that this opens for diagnosis of the pulsation ofthese stars. We present a first application to the strongly magneticstar HD 166473. While the predicted effect could not be observed(possibly due to the low pulsation amplitude), marginal detection ofvariation of the mean magnetic field modulus with the pulsationfrequency is achieved.

We have used the new broadband capabilities of the Mopra telescope to map the distribution of 26 different molecular transitions in an approximately 1 degree square region of the southern Galactic plane (the G333/RCW106 giant molecular cloud complex). The aim is to addresss observationally some of the key questions about the dynamical processes surrounding massive star formation (e.g. massive stellar winds and large-scale galactic flows) and their relative importance in regulating the star formation process. These dynamical processes help drive the turbulent motions, which are ubiquitous in giant molecular clouds (GMCs). The multi-molecular line nature of this survey is what distinguishes it from similar surveys and is crucial for gaining a clear picture of the energetics and dynamics of the gas. Investigating and understanding the chemistry of this region is a necessary part of the project if the molecular line observations are to be interpreted physically.

We demonstrate the eclipsing binary detection performance of the Gaia variability analysis and processing pipeline using Hipparcos data. The automated pipeline classifies 1 067 (0.9%) of the 118 204 Hipparcos sources as eclipsing binary candidates. The detection rate amounts to 89% (732 sources) in a subset of 819 visually confirmed eclipsing binaries, with the period correctly identified for 80% of them, and double or half periods obtained in 6% of the cases.

Atmospheric field experiments were made at the French-Italian station of Concordia at Dome C during several years. These experiments were limited to the summer season. In 2005 Concordia has become a permanent base, this allowed to carry out STABLEDC (STudy of the Atmospheric Boundary Layer Environmental at Dome C plateau station) that is an atmospheric field experiment of the duration of one year. The aim of STABLEDC was to study the processes occurring in the long-lived stable and the weak convective atmospheric boundary layers, observed during winter and summer, respectively, and to collect the relevant parameters for the atmospheric models. Both in situ and ground based remote sensing instruments have been used to monitor the meteorological parameters. The first part of the paper gives a brief illustration of the objectives of the field experiment, and a description of site and instrumentation. The second part shows the behaviour of some micrometeorological parameters: temperature, wind speed, sensible heat flux. The surface radiation balance components are also shown. Finally some experimental activities are proposed.

Angular momentum is playing a key role during the collapse of prestellar cores since it is leading to disk formation and to some extent to binary formation. On the other hand, it has long been recognized that the stars possess a tiny fraction of the initial momentum that their parent clouds retain, an issue known as the “angular momentum problem”. In these lectures, we attempt to present the most recent calculations performed to investigate the angular momentum transport and the influence angular momentum has, during the collapse of prestellar cores. After a brief introduction of the star formation context and a broad description of the important features within collapsing cores, we discuss the so-called catastrophic braking. Indeed when magnetic field and rotation axis are aligned, the magnetic braking is so efficient that the formation of early disks is completely prevented. We then present the various studies which have attempted to explore the robustness of this efficient transport including influence of non-ideal MHD, misalignment between magnetic field and rotation axis and turbulence. While the role of the first, is not entirely clear; the two other effects diminish the efficacity of the magnetic braking making the issue less severe than in the pure ideal MHD aligned configuration. Finally, we discuss the fragmentation of low and high mass cores with particular emphasis on the impact of the magnetic field. In particular, we discuss the drastic stabilization that magnetic field has on low mass cores and the possible solution to this apparent conundrum. In the context of high mass stars, its influence is much more limited reducing the number of fragments by a factor of the order of two. However when both radiative feedback and magentic field are included, the fragmentation is very significantly reduced.

Recent developments in coronagraphy have increased the reachable dynamic range limit of telescopes and thus opened the possibility for the imaging of fainter and fainter companions. They rely on a series of modifications of the original concept involving amplitude and phase masks in either the pupil or the image plane. They are designed to operate optimally at one wavelength. In this paper we first study the chromatic leakage in Pupil Apodised Lyot Coronagraphs and then present a theoretical solution that create a polychromatic null while maximizing the photon flux from the companion. Finally we discuss a promising experimental implementation of this solution using interferometric apodisations.

The observed brightness fluctuations and large-scale structures on thesurface of the Red Supergiant Betelgeuse make the star a prime targedfor future interferometric measurements. At the same time, they openthe possibility to resolve these structures in numerical radiationhydrodynamics simulations of the entire star. After some general remarksabout the possibility and difficulties of 3D simulations of stars ingeneral results of such calcuations of the outer convective envelope andthe atmosphere of a Red Supergiant and a star on the Asmyptotic GiantBranch are presented. These show that numerous short-lived small-scalesurface granules coexist with a few long-lived large-scale envelopeconvection cells. Pressure fluctuations deform the star and influencethe surface convection. The convective “granulation" pattern differsfrom the solar one. Convection and pulsations produce large-scalehigh-contrast brightness fluctuations that might explain the observedluminosity variations and surface “spots”. Shock waves and supersonicatmospheric velocities manifest themselves in broad line profiles.

A possible method of pupil apodization using Zernike's phase contrastis presented. I recall the phase contrast principle and show through numericalsimulations that it may be used to generate an apodization using very simpleoptics in the monochromatic case. I also demonstrate that the generalformalism for Lyot and Roddier & Roddier coronagraphy can be extended to theZernike case. This may improve the quality of the simulations undertakento demonstrate the technique's performances.

We investigate the occurrence of water vapour signatures in a total of 10 red giants in the solar neighbourhood at mid-infrared wavelengths (12 μm). With the use of high resolution spectra from TEXES and synthesized spectra based on MARCS model atmospheres, we analyse the differences and discuss plausible causes. These include abundance adjustments, the addition of non-photospheric components (MOLspheres) and a different temperature profile.