We present the pipeline processing (for photometry and spectrophotometry) primarily based on the comparison of the observation with a prediction from the spectral energy distribution and total flux of the source and a set of parameters modelling the instrument properties observation-to-observation. Experiments on G white light calibration yield residuals well below one mmag for most of the cases, but for extreme colour stars. For blue and red spectra, tests up to now yield residuals significantly smaller than the observational noise, except for sources with very strong spectral features, which present flux residuals of 2–3% in the spectral lines (at G = 15). Work continues to account for all instrumental effects, to add complexity to the instrument model and to improve the processing pipeline.

We have recently identified a previously unknown radial migration mechanism resulting from the overlap of spiral and bar resonances in galactic discs (Minchev & Famaey 2010; Minchev et al. 2010b). This new mechanism is much more efficient than mixing by transient spirals and its presence is unavoidable in all barred galaxies, such as our own Milky Way. The consequences of this are a strong flattening in the metallicity gradient in the disc, an extended disc profile, and the formation of a thick disc component, all taking place in only a couple of Gyr. This timescale is drastically shorter than previously expected and thus can put strong constraints on the longevity, strength and pattern speeds of the Galactic bar and Spiral Structure.

The maximum luminosity of protostars forming in molecular clouds isinvestigated as a function of the parent cloud mass on the basis of arich cloud sample searched for in the literature. In total, we gathered499 molecular clouds among the published data, out of which 243clouds are found to be associated with candidates for protostars selectedfrom the IRAS point source catalog. A diagram of the maximum stellarluminosity in each cloud and the parent cloud mass shows that theyoung stars in the clouds associated withregions are apparentlymore luminous than those in clouds away from HIIregions over theentire cloud mass range investigated (1 < MCL/M⊙ < 106).In addition, wefound that there are well-defined upper and lower limits in themaximum stellar luminosity distribution with the lower limit having asteeper dependence on the cloud mass(LMAX ∝ MCL1.5) than the upperone (LMAX ∝ MCL0.8). All these featurescould be naturally accounted forif we assume that the luminosity function of protostars is controlled by thecloud mass and the external pressure imposed on the cloud surface. Weintroduce a simple model for the stellar luminosity function as afunction of these quantities.

We discuss the determination of fundamental parameters of "normal" hot, massive OB-type stars, namelytemperatures, luminosities, masses, gravities and surface abundances. We also present methods used to derive properties of stellar winds - mass-loss rates and wind velocities from early-type stars.

I review recent studies of the emission-line regions in Orion and M 17. Both have similar geometries, a bubble of hot shocked gas surrounding the central star cluster, with H+, H0, and H2 regions, often referred to as H II regions, PDRs, and molecular clouds, forming successive shells on the surface of a molecular cloud. The magnetic fields in the H0 regions have been measured with 21 cm Zeeman polarization and are found to be 1 – 2 dex stronger than the field in the diffuse ISM. The regions appear to be in rough hydrostatic equilibrium. The H+ region is pushed away from the star cluster by starlight radiation pressure. Since most starlight is in ionizing radiation, most of its outward push will act on the H+ region and then on to the H0 region. The magnetic pressure in the H0 region balances the momentum in starlight and together they set the location of the H0 region. The picture is that, when the star cluster formed, it created a bubble of ionized gas which expanded and compressed surrounding H0 and H2 regions. The magnetic field was amplified until its pressure was able to support the momentum in starlight. This offers a great simplification in understanding the underlying physics that establishes parameters for PDR models.

In this paper we review the progress towards the deployment of alarge "PILOT-like" telescope at Concordia Station, Dome C. PILOT isa proposed 2.4 m optical/IR telescope that will cost in excess of EUR10 m, and is thus representative of the scale of facility that willtransform Concordia into a significant international observatory. Adesign study of PILOT, funded by the Australian government, iscurrently underway. We describe the current status of this designstudy, and discuss the implications that major internationalprojects such as PILOT hold for the future of Antarctic astronomy atConcordia.

We summarize the main highlights from ISO observations towards Sgr B2 and Orion KL in the far–IR domain (~43 to 197 μm). Both Star–Forming Regions are among the best sources to construct a template for more distant and unresolved regions (e.g., extragalactic). We stress some peculiarities in the interpretation (excitation and radiative transfer) of far–IR spectral lines and dust continuum emission.

We use the mass-to-light gradients in early-type galaxies to infer the global dark matter fraction, fd = Md/M*, for these systems. We discuss implications about the total star formation efficiency in dark-matter halos and show that the the trend of fd with mass produces virial mass-to-light ratios which are consistent semi-analitical models. Preliminary kurtosis analysis of the quasi-constant M/L galaxies in Romanowsky et al. seems at odd with Dekel et al. simulations.

I present an simple, introductory review text, focusing on recent deep field studies using radio telescopes, including high-resolution, wide-field VLBI observations. The nature of the faint radio source population is discussed, taking into account complimentary data and results that are now available via the sub-mm, IR, optical and X-ray wave-bands. New developments regarding the increased sensitivity of VLBI and an expansion in the instruments field-of-view are also presented. VLBI may be an important tool in recognising distant, obscured AGN from the “contaminant” star forming galaxies that now dominate lower-resolution, sub-arcsecond and arcsecond radio observations.

Near infrared observations of reflection nebulae have set the historical ground for thediscovery of interstellar PAHs, but since, space observations have focused on their mid-IRfeatures, and data shortward of 5   μm have remained scarce. TheSpitzer/IRAC images in the 3.6 and 4.5   μm channels do show that thenear-IR emission from small dust particles is ubiquitous across the Galaxy, but provide nospectroscopic information. To investigate the nature of this near-IR dust emission, wehave obtained AKARI spectroscopic observations, over the 2.5−5   μmspectral range, for a set of archetype PDRs mapped with the Spitzer spectrometer at mid-IRwavelengths. These AKARI data supplement earlier observations with the SWS ISOspectrometer, in providing the gain in sensitivity needed to observe low excitationsources, and the spatial information required to spatially correlate near-IR spectroscopicsignatures with physical conditions and observed changes in mid-IR spectra. This paperpresents the first results of the data analysis, in relation to two open questions oninterstellar PAHs. (1) Is there an evolutionary link from aliphatic carbon dust to PAHs?(2) What is the origin of the near-IR dust continuum? The AKARI spectra display featureslongward of the main 3.29   μm PAH feature, and continuum emission. Theintensity ratio between the features ascribed to aliphatic CH bonds and the3.29   μm aromatic band, varies spatially in a way that may beinterpreted as evidence for aromatization of the smallest dust particles byphoto-processing. The continuum displays a striking step-increase across the3.29   μm feature. We also present a spectrum of a photodissociationregion with a feature at 4.65   μm, which has been speculated to berelated to the CD stretch in aliphatic hydrocarbon side-groups on PAHs.

In the study of extended sources such as star forming regions, galactic planetary nebulae or comets wide field integral-field spectroscopy at high spectral resolution in the infrared, would be the ideal tool. It is shown that an imaging FTS (IFTS) is the only instrument which can combine a wide field, up to ~10', with a spectral resolution ≥105. At Dome C, in the 2 to 25 μm region, as instrument of a 3-m class telescope, a wide-field IFTS would have no equivalent in space and on ground. It can take full advantage of all the astronomical properties of this site, in particular the lowest thermal background emission conditions on Earth. A program to simulate the expected performances has been developed. At the highest resolution the best sensitivity implies the use of narrow-band filters on the emission lines of interest.

The processing of dust in shocks in the interstellar medium can lead to changes in the dust to gas mass ratio and also to a radical evolution of the dust size distribution. Here we focus on the important results of numerical models that simulate the impact of shocks on the interstellar dust size distribution in molecular clouds and in the warm intercloud medium. We emphasize the necessity of detailed modelling of the grain charging processes and the grain inertia in order to unravel the complexities and consequences of the dust dynamics in shock waves.

We review the experimental evidence for Einstein's special and general relativity. A variety of high precision null experimentsverify the weak equivalence principle and local Lorentz invariance,while gravitational redshift and other clock experiments support localposition invariance. Together these results confirm theEinstein Equivalence Principle which underlies the concept thatgravitation must bedescribed by a metric theory.Solar system experiments that test the weak-field, post-Newtonianlimit of metric theories strongly favorgeneral relativity. The BinaryPulsar provides tests of gravitational-wave dampingand of strong-field general relativity. Recently discovered binarypulsar systems may provide additional tests. Ongoing and futureexperiments, such as the Gravity Probe B GyroscopeExperiment, satellite tests of the Equivalence principle, and tests ofgravity at short distance to look for extra spatial dimensions could constrain extensions of general relativity.Laser interferometricgravitational-wave observatories on Earth and in space may provide new testsof gravitational theory via detailed measurements of the properties of gravitational waves.

Diffusion in cool B stars of the main sequence has been shown to strongly affect opacities and convection in cool B stars of the main sequence. We show here that diffusion in B stars maintains or enhances the excitation ofpulsations in these stars. This result conflicts with observations as cool B starsthat show evidence of diffusion, the HgMn stars, are stable to the currentdetection level. We discuss possible implications of this discrepancy for the models.

As red supergiants are the largest and brightest stars, they are ideal targets for the new generation of sensitive, high resolution instrumentation that provides spectrophotometric, interferometric, astrometric, and imaging observables. The interpretation of the complex stellar surface images requires numerical simulations of stellar convection that take into account multi-dimensional time-dependent radiation hydrodynamics with realistic input physics. We show the results obtained with the synergy between the radiative hydrodynamics code CO5BOLD and the post-processing radiative transfer code Optim3D. Such simulations support a proper and quantitative analysis of these observations, and the observations provide the theoretical work with strong constraints.

Near-infrared (NIR; 2.5–5 μm) low-resolution(λ/Δλ ~ 100) spectra were obtained for anumber of Galactic and extragalactic objects with the Infrared Camera (IRC) in the AKARIwarm mission. These data provide us with the first opportunity to make a systematic studyof the 3.3–3.5 μm PAH features in a galactic scale as well as within anobject. Whereas the 3.3 μm band is well resolved in most spectra, the3.5 μm band is not clearly separated from the 3.4 μmband in the IRC spectrum. The intensity ratio of the summation of the 3.4 and3.5 μm bands to the 3.3 μm band shows a tendency toincrease towards the Galactic center, although a large variation in the ratio is also seenin a local scale. A search for deuterated PAH features in the 4 μm regionis carried out in IRC NIR spectra. Emission lines originating from the ionized gastogether with the detector anomaly hamper an accurate search at certain wavelengths, butlittle convincing evidence has so far been obtained for the presence of significantfeatures in 4.2–4.7 μm. A conservative upper limit of a few percents isobtained for the integrated intensity ratio of the 4.4–4.7 μm possiblefeatures to the 3.3–3.5 μm PAH features in the spectra so farobtained.

In a first part of the paper we give a simple introduction to the free space propagation of light at the level of a Master degree in Physics. The presentation promotes linear filtering aspects at the expense of fundamental physics. Following the Huygens-Fresnel approach, the propagation of the wave writes as a convolution relationship, the impulse response being a quadratic phase factor. We give the corresponding filter in the Fourier plane. As an illustration, we describe the propagation of wave with a spatial sinusoidal amplitude, introduce lenses as quadratic phase transmissions, discuss their Fourier transform properties and give some properties of Soret screens. Classical diffractions of rectangular diaphragms are also given here. In a second part of the paper, the presentation turns into the use of external occulters in coronagraphy for the detection of exoplanets and the study of the solar corona. Making use of Lommel series expansions, we obtain the analytical expression for the diffraction of a circular opaque screen, giving thereby the complete formalism for the Arago-Poisson spot. We include there shaped occulters. The paper ends up with a brief application to incoherent imaging in astronomy.

The structure function (or the power spectrum)of phasefluctuations induced by atmospheric turbulence is the mainquantity which must be known to optimize the High AngularResolution techniques used for astronomical observations. Itallows to evaluate the state of coherence of the perturbedwavefronts. In this paper are firstly recalled classical resultsconcerning the propagation of the luminous waves through theterrestrial atmosphere and consequently the image formation. Then,different models generally used to describe the optical effects ofatmospheric turbulence, due to numerous thin layers, are presentedand their influence discussed. A second order statistical analysisis performed and the coherence parameters deduced. The necessityof measuring these parameters appears evident and dedicatedmonitors must be built.

The influence of a magnetic field on the broadening of spectral lines and transition arrays in complex spectra is investigated. The anomalous absorption or emission Zeeman pattern is a superposition of many profiles with different relative strengths, shifts, widths, asymmetries and sharpnesses. The σ and π profiles can be described statistically, using the moments of the Zeeman components. We present two statistical modellings: the first one provides a diagnostic of the magnetic field and the second one can be used to include the effect of a magnetic field on simulated atomic spectra in an approximate way.

In this contribution, we present our recent effort in understanding the solar small-scale magnetic field. Firstly, with the unique data from MDI/SOHO in an interval embodying solar cycle 23, we find three categories of small-scale magnetic elements, and their number variations shows no correlation, anti-correlation and correlation with sunspots, respectively. The possible sources for the three categories of small-scale magnetic elements are discussed. Secondly, by the observations from SOT on board Hinode, we study the properties of vector magnetic field in quiet Sun. The following results are summarized. (1) Two categories of horizontal magnetic elements are disclosed, and most of horizontal elements are associate with the emergence of U-loop. (2) The magnetic field of quiet region is obviously non-potential. The filigrees and network bright points are characterized by strong longitudinal field, large electric helicity and free energy density. (3) For quiet region, the intra-network region displays a predominance of weak field concentration, but network region shows the coexisting of weak field with strong field; For polar region, the strong field occupies 6.7% of the region. (4) On quiet region, the magnetic field mainly resides in the inter-granular lanes. By the observation, we reconstruct an average granular model, for which the detailed distributions of vector fields, Doppler velocity and intensity are obtained.