We present a tomographic reconstruction of polar plumes as observed in the Extreme Ultraviolet in January 2010. Plumes are elusive structures visible in polar coronal holes that may play an important role in the acceleration of the solar wind. However, despite numerous observations, little is irrefutably known about them. Because of line of sight effects, even their geometry is subject to debate. Are they genuine cylindrical features of the corona or are they only chance alignments along the line of sight? Tomography provides a means to reconstruct the volume of an optically thin object from a set of observations taken from different vantage points. In the case of the Sun, these are typically obtained by using a solar rotation worth of images, which limits the ability to reconstruct short lived structures. We present here a tomographic inversion of the solar corona obtained using only 6 days of data. This is achieved by using simultaneously three space telescopes (EUVI/STEREO and SWAP/PROBA2) in a very specific orbital configuration. The result is the shortest possible tomographic snapshot of polar plumes. The 3D reconstruction shows both quasi-cylindrical plumes and a network pattern that can mimic them by line of sight superimpositions. This suggests that the controversy on plume geometry is due to the coexistence of both types of structures.


Caustics are formally singular structures that frequently form in collisionless media. The non-negligible velocity dispersion of dark matterparticles renders their density finite. We evaluated the maximum density ofthe caustics within the framework of secondary infall model of formation ofdark matter haloes. The result isthen used to demonstrate that caustics can be probedby properly stacking the weak-lensing signal of about 600 haloes. CFHTLS accompanied by X-ray observations and the space-based experiments like SNAP or DUNE can provide us with the required statistics.The extension of our results to more realistic models including the effects of mergers is outlined.


We present here a study of the Infrared properties ofAsymptoticGiant Branch stars (hereafter AGB) based on existing databases,mainly from space-borne experiments. Preliminary results about Cand S stars are discussed, focusing on the topics for which futureInfrared surveys from Antarctica will be crucial. This kind ofsurveys will help in making more quantitative our knowledge of thelast evolutionary stages of low mass stars, especially for whatconcerns luminosities and mass loss.

The dynamics of stars and gas appear markedly different in flocculent, tidally induced and quasi-stationary spiral galaxies. Numerical simulations show that the gas and stars exhibit fairly chaotic dynamics during a tidal interaction, unlike the predictions of density wave theory. For a flocculent galaxy, the stars and gas tend to be situated in potential minima associated with the stellar distribution. I will demonstrate a possible observational test to distinguish between drivers of spiral structure by comparing the ages of stellar clusters, using the results of the simulations as an example.

With high resolution simulations, we are also starting to resolve giant molecular clouds, and can thus relate the properties of these clouds to the presence of spiral structure. Calculations so far suggest that spiral structure simply defines where the clouds form, rather than directly triggering star formation. In the last section of this review, I highlight recent efforts to produce synthetic HI and CO observations from numerical simulations.

Our aim is to study the evolution of tidal dwarf galaxies. The firststep is to understand whether a model galaxy without Dark Matter cansustain the feedback of the ongoing star formation. We present testsof the evolution of models in which star formation efficiency,temperature threshold, initial distribution of gas and infall arevaried. We conclude that it is feasible to keep a fraction of gasbound for several hundreds of Myr and that the development of galacticwinds does not necessarily stop continuous star formation.

We present the results from an optical monitoring campaign aimed at studying theafterglow properties of the short GRB 100816A. We implemented a new way of processing theSwift-BAT data, and based on it we reclassified this burst as short,discarding the initial classification as long. Observations were carried out mainly withthe GTC Telescope within the four following days after the burst to investigate theoptical photometry of its afterglow, and a year later to localize the host. We completedthe optical imaging with the 1.23 m and 3.5 m CAHA Telescopes. We built and fitted thenIR-optical SED for the characterization of the host. The best fit of the SED(χ2/d.o.f. = 1.656) obtained for assumed values of a solarmetallicity, and an extinction of AV = 0.2mag is obtained fora starburst galaxy with a dominant stellar population aging about 360 Myr.

The science case for FIR/Submm surveys of the extragalactic sky to be carried out from Dome C is reviewed. The main questions concerning the formation and evolution of galaxies making up the CIRB are outlined and opportunities to exploit Dome C unique observing conditions through single-dish observations are discussed.

Recent lyot coronagraphic performances achieved with adaptive optics (AO) instruments ADONIS/SHARPII, PUEO/KIR and NAOS/CONICA are presented and compared to detection limit predictions estimated with a simple analytic approach. The aim is to discuss and to determine the different observing limitations, to optimize the use of the instrument capabilities and to support the design of future instruments in the specific field of high contrast observations.

A brief summary of some aspects of atomic physics theory useful for stellar atmospheres is given.

Contrary to what is still often admitted when studying the chemical evolution of galaxies, the element abundances observed in stellar atmospheres are often not representative of the initial composition of the protostellar nebula. Element abundances may be altered during stellar evolution by atomic diffusion and/or accretion, if not by nuclear reactions. Atomic diffusion occurs in any type of stars, with time scales extremely different according to the macroscopic motions with which they have to compete. Accretion may occur in solar type stars during planetary formation, which seems to be a common process. Following the success of helioseismology, asteroseismology is now becoming a fundamental tool for penetrating the secrets of the internal structure of stars. In particular it may be used to derive their internal abundances compared to the observed ones. In the present paper, I focus on main-sequence stars. I first recall the situations where abundance stratification can act for exciting or stabilizing stellar oscillations, second I describe how seismic observations can be used to derive abundance gradients inside stars.

We present the scientific case for a high resolution spectro-imagerin the mid-IR that wouldbe dedicated to the mapping of H2 emission in its four lowest rotational transitions, at 28.2, 17.0, 12.3 and 9.7 micron with a spectral resolution ~104 sufficient to provide kinematical distances ingalaxies. The proposed instrument on a 2 m-class telescope will be most sensitive to H2 line emission simultaneously extended and structured at small scale, in gas at temperatures higher than 80 K. Colder H2,which may contribute most of the baryonic dark matter ingalaxies, will be traced by the emission of glitters of warm H2heated, throughout the medium, by the dissipation of omnipresent turbulence.The main scientific objectives are to (i) directly measure themass and temperature distribution of the warm H2, far from star formingregions, in particular in low metallicity environments where thetraditional tracers of H2 (CO, dust emission) fail, (ii) trace the dissipation of turbulence in the perspective of building a global view of the star formation process in galaxies and (iii)trace baryonic dark matter in the form of cold H2in a large sample of galaxies along the Hubble sequence.

Photodissociation regions (PDRs) are gas phases in which far-ultraviolet radiation plays a significant role in the heating and/or chemistry (Tielens & Hollenbach 1985). X-ray dissociation regions (XDRs) are regions in which X-rays dominate the heating and/or chemistry (Moloney et al. 1996). Much progress has been mode in modeling PDRs (e.g., Röllig et al. 2007) and XDRs (e.g., Meijerink et al. 2007) and the models predict several line intensities and line ratios of atomic and molecular species that are good diagnostics for discriminating between the two. I will discuss the theoretical models in light of the most recent observations.

We explore the possibility of detecting and characterising the warp of the stellar disc of our Galaxy using the synthetic Gaia data and the UCAC4 proper motion catalogue. We develop a new kinematic model for the galactic warp. We generate random realisations of test particles which evolve in a realistic Galactic potential warped adiabatically to various final configurations. The Gaia selection function, its errors model and a realistic 3D extinction map are applied to mimic three tracer populations: OB, A and Red Clump stars. A family of Great Circle Cell Counts (GC3) methods is used. They are ideally suited to find the tilt and twist of a collection of rings, which allow us to detect and measure the warp parameters. Moreover, We look for the kinematic signature of the warp in the μb proper motions of stars as a function of galactic longitude. Using the UCAC4 proper motions, we do not obtain a similar trend as the one we expect from our warp model. We explore a possible source of this discrepancy in terms of systematics caused by a residual spin of the Hipparcos celestial reference frame (HCRF) with respect to the extra-galactic inertial one.

Antarctica offers unique conditions for ground-based observations, such as low sky background in the infrared, improved seeing, and low turbulence and scintillation noise. These properties are particularly beneficial to imaging, precision photometry, and infrared observations. It may be less clear if Antarctica offers equally compelling advantages for spectroscopy, in particular in the optical domain. However, scientific programmes that make use of imaging (or 3D) spectroscopy for selected follow-up studies of IR surveys, long-termmonitoring of extended targets and resolved stellar population studies in crowded fields, also benefit from the site conditions at Dome C.

The present work is placed in the framework of the preparation for the interpretation of the seismic space data from the space mission CoRoT. In this context, rotation have become one of the most limiting factors when analysing the observed spectra of stars. A general view on the effects of rotation on the oscillations is given from the point of view of a linear perturbation analysis. As well, the latest results about the effect of shellular rotation on adiabatic oscillation frequencies are addressed. Finally, the role of rotation on asteroseismic diagnostics is discussed. In particular, échélle diagrams and analysis of rotation profile variations are examined.

This paper deals with adaptive optics in the framework of very high-contrast astronomical imaging. Starting from a brief global overview of classical adaptive optics (AO) systems, the specificities and main characteristics of extreme AO (XAO) systems are exposed. Along the way from AO to XAO, some relevant points (relevant with respect to the goals claimed by high-contrast imaging techniques) are emphasized.

Low-frequency oscillations are unstable in a wide range of stellar models and have been detected in a number of B-type stars. For such modes, even a moderate rotation significantly affects amplitude distribution over stellar surface and hence their visibility conditions. Adopting the traditional approximation, we study effects of rotation on relative amplitudes in photometric passbands and in radial velocity. We present numerical results for unstable modes in a selected stellar model of a 6 M๏ main sequence star. The goal is to show how observable amplitudes, which are tools for mode identification, depend on the rotation rate and on the aspect angle.

The papers in this volume represent a broad spectrum of observational, theoretical, and computational astrophysics, sharing as a unifying core the Disk-Halo Interaction in the Milky Way and other spiral galaxies. This topic covers a wide range of Galactic and extra-galactic research, built on a foundation of numerous and diverse physical processes. This summary groups the papers according to six themes, with some historical background and finally a look to the future. The final message is that the astrophysical techniques discussed and reviewed at this conference will grow over the next decade to answer even more fundamental questions about galaxy evolution and the history of the universe.

Directional information should play a significant role for a firm detection of the galactic dark matter. We developed a prototype three-dimensional gaseous tracking device for a direction-sensitive dark matter direct detection. We investigated the performance of the prototype detector and demonstrated a direction-sensitive dark matter search experiment in a surface laboratory. We set the first limit on the spin-dependent WIMP (Weakly Interacting Massive Particles)-proton cross s ection by a direction-sensitive method.

Whereas the understanding of most phases of stellar evolution made considerable progress throughout the whole of the twentieth century, stellar formation remained rather enigmatic and poorly constrained by observations until about three decades ago, when major discoveries (e.g., that protostars are often associated with highly collimated jets) revolutionized the field. At this time, it became increasingly clearer that magnetic fields were playing a major role at all stages of stellar formation. 
We describe herein a quick overview of the main breakthroughs that observations and theoretical modelling yielded for our understanding of how stars (and their planetary systems) are formed and on how much these new worlds are shaped by the presence of magnetic fields, either those pervading the interstellar medium and threading molecular clouds or those produced through dynamo processes in the convective envelopes of protostars or in the accretion discs from which they feed.