Depending on whom you ask, PAHs are either the smallest dust particles or the largestgas-phase molecules in space. Whether referred to as gas or dust, these PAHs can containup to20% of the total cosmic carbon abundance and as such also play an important role inthe carbon chemistry of protoplanetary disks. The interpretation of PAH bands is often acomplex procedure involving not only gas physics to determine their ionization stage andtemperature, but also radiative transfer effects that can bury these bands in a strongthermal continuum from a population of larger dust particles.

PAHs are most readily seen in the spectral energy distributions (SEDs) of disks aroundHerbig AeBe stars where they are photoprocessed by the stellar radiation field. Resolvedimages taken in the PAH bands confirm their origin in the flaring surfaces ofcircumstellar disks: if the SED is consistent with a flat disk structure (lessilluminated), there is little or no evidence of PAH emission. The very low detection ratesin the disks around T Tauri stars often require an overall lower abundance of PAHs inthese disk surface as compared to that in molecular clouds.

In this review, I will adress three aspects of PAHs in protoplanetary disks: (1) Do PAHsform in protoplanetary disks or do they originate from the precursor molecular cloud? (2)Is the presence of PAH features in SEDs a consequence of the disk structure or do PAHs infact shape the disk structure? (3) How can we use PAHs as tracers of processes inprotoplanetary disks?

PILOT is proposed as a partnership between Australia and Europe todevelop a 2.4 m optical/infrared telescope for Dome C,Antarctica. Funding for a detailed designed study is being soughtfrom Australian sources, with a view to commencing construction inearly 2008. The current “strawman” design is for an f/10 dualNasmyth configuration with provision for both a silicon carbide fasttip-tilt secondary mirror for the thermal infrared, and an adaptivesecondary mirror to achieve diffraction-limited imaging atwavelengths as short as V-band.


The formation of inorganic dust in circumstellar environments of evolved stars is poorly understood. Spectra of molecules thought to be most important for the nucleation, i.e. AlO, TiO, and TiO2, have been recently detected in the red supergiant VY CMa. These molecules are effectively formed in VY CMa and the observations suggest that non-equilibrium chemistry must be involved in their formation and nucleation into dust. In addition to exploring the recent observations of VY CMa, we briefly discuss the possibility of detecting these molecules in the “dust-poor” circumstellar environment of Betelgeuse.

We have compiled a new catalogue of open clusters in the Galaxy which updates the previous catalogues of Lyngå (1987) and of Mermilliod (1995) (included in the WEBDA database). New objects and new data, in particular, data on kinematics (proper motions, radial velocities) that were not present in the old catalogues, have been included. Virtually all the clusters (1622) presently known were included, which represents an increment of about 450 objects relative to the Lyngå (1987) catalogue. The catalogue is presented in a single table containing all the important data (positions, reddenings, distances, ages, kinematics) which makes it easy to use. The catalogue includes mean absolute proper motions for hundreds of open clusters (Dias et al. 2001, 2002a) obtained using the Tycho2 proper motions. Unpublished mean radial velocities of several dozens of clusters are also presented in this work. The catalogue is being constantly updated and the latest version can be accessed on-line at http://www.astro.iag.usp.br/~wilton/ were more data such as membership probabilities for individual stars can also be accessed.

I review the development of ideas regarding the angular momentumevolution of solar-type stars, from the early 60's to the most recentyears. Magnetic fields are the central agent that dictates therotational evolution of solar-type stars, both during the pre-mainsequence, through star-disk magnetic coupling, and during the mainsequence, through magnetized winds. Key theoretical developments aswell as important observational results are summarized in this review.

The development of fast numerical methods for multilevel radiative transfer (RT) applications often leads to important breakthroughs in astrophysics, becausethey allow the investigation of problems that could not be properly tackled using the methods previously available. Probably, themost familiar example is the so-called Multilevel Accelerated Λ-Iteration (MALI) technique of Rybicki & Hummerfor the case of a local approximate operator,which is based on Jacobi iteration. However, there are superior operator-splitting methods, based on Gauss-Seidel (GS) and Successive Overrelaxation (SOR) iteration, which provide a dramatic increase in the speed with which non-LTE multilevel transfer problems can be solved in one, two and three-dimensional geometries. Such RT methods, which were introduced by Trujillo Bueno & Fabiani Bendicho ten years ago, are the main subject ofthe first part of this paper. We show in some detail how they can be applied for solving multilevel RT problems in spherical geometry, for both atomic and molecular line transitions. The second part of the article addresses the issue of the calculation of the molecular number densities when the approximation of instantaneous chemical equilibrium turns out to be inadequate, which happens to be the case wheneverthe dynamical time scales of the astrophysical plasma under considerationare much shorter than the time needed by the molecules to form.

The fullerene C60 has four infrared active vibrational transitions at 7.0, 8.5,17.5 and 18.9 μm. We have previously observed emission features at17.4 and 18.9 μm in the reflection nebula NGC 7023 and demonstratedspatial correlations suggestive of a common origin. We now confirm the identification ofthese features with C60 by detecting a third emission feature at7.04 ± 0.05μm at a position of strong 18.9 μm emissionin NGC 7023. We also report the detection of these three features in the reflection nebulaNGC 2023. We show with spectroscopic mapping of NGC 7023 that the 18.9 μmfeature peaks on the central star,that the 16.4 μm emission feature dueto PAHs peaks between the star and a nearby photodissociation front,and that the 17.4μm feature is a blend of a PAH feature and C60. The derivedC60 abundance is consistent with that from previous upper limits and possiblefullerene detections in the interstellar medium.

Heartbeat stars are a relatively new class of eccentric ellipsoidal variable first discovered by Kepler. An overview of the current field is given with details of some of the interesting objects identified in our current Kepler sample of 135 heartbeats stars. Three objects that have recently been or are undergoing detailed study are described along with suggestions for further avenues of research. We conclude by discussing why heartbeat stars are an interesting new tool to study tidally induced pulsations and orbital dynamics.

In the last five years our knowledge of magnetism in early-type stars has significantly improved because of the new gen- eration of high-resolution spectropolarimeters (ESPaDOnS@CFHT, Narval@TBL, HARPSpol@ESO). The success of the Magnetism in Massive Stars (MiMeS) Project, for example, has greatly improved our understanding of the magnetic properties of massive early-type stars; however, it was mainly focused on single stars. Summarized here is our general understanding of stellar magnetism in early-type stars and the recent findings from the MiMeS project. As recent results suggest a significant fraction of early-type stars are in binaries, this implies that the interplay between magnetic fields and binarity has yet to be investigated in any significant detail. To this end, the current analysis of the recently discovered magnetic field in the rapidly-rotating secondary star of the close, massive binary system known as Plaskett’s star – a unique system that is testing our current theories of binarity and magnetism in early-type stars, and a target for investigation in the recently accepted Binarity and Magnetic Interactions in various classes of Stars (BinaMIcS) Large Programs at CFHT and TBL – is discussed.

We present a progress report on including all the lines in the linelists,including all the lines in the opacities, including all the lines inthe model atmosphere and spectrum synthesis calculations, producinghigh-resolution, high-signal-to-noise atlases that show (not quite) allthe lines, so that finally we can determine the properties of stars froma few of the lines.

Model atoms are an integral part in the solution of non-LTE problems. They comprise the atomic input data that are used to specify the statistical equilibrium equations and the opacities and emissivities of radiative transfer. A realistic implementation of the structure and the processes governing the quantum-mechanical system of an atom is decisive for the successful modelling of observed spectra. We provide guidelines and suggestions for the construction of robust and comprehensive model atoms as required in non-LTE line-formation computations for stellar atmospheres. Emphasis is given on the use of standard stars for testing model atoms under a wide range of plasma conditions.

Our current picture of black hole gravitational collapserelies on two assumptions: i) the resultingsingularity is hidden behind an event horizon– weak cosmic censorship conjecture – and ii) spacetimeeventually settles down to a stationarity state.In this setting,it follows that the minimal area containing an apparent horizonis bound by the square of the total ADM mass (Penrose inequality conjecture).Following Dain et al. (2002), we construct numerically a familyof axisymmetric initial data with one or several marginallytrapped surfaces. Penrose and related geometric inequalitiesare discused for these data. As a by-product, it is shownhow Penrose inequality can be usedas a diagnosis for an apparent horizon finder numerical routine.

Submillimetre/TeraHertz (e.g. 200, 350, 450 μm) astronomy is the prime technique to unveil the birth and early evolution of a broad range of astrophysical objects. A major obstacle to carry out submm observations from ground is the atmosphere. Preliminary site testing and atmospheric transmission models tend to demonstrate that Dome C could offer the best conditions on Earth for submm/THz astronomy. The CAMISTIC project aims to install a filled bolometer-array camera with 16×16 pixels on IRAIT at Dome C and explore the 200-μm windows for potential ground-based observations.

Mass-loss rates are one of the most relevant parameters determining the evolution of massive stars. In particular, the rate at which the star loses mass during the red-supergiant (RSG) phase is the least constrained by the observations or theory. In this paper, we show how the mass loss during the RSG phase affects the later evolution of the star, as well as the final type of supernova towards which it leads. We also discuss some possibilities to discriminate between blue stars that went through a RSG phase and those which remained in the blue part of the Hertzsprung-Russell diagram.

We present a new multi-fluid, grid-based magnetohydrodynamics (MHD) code PIERNIK, which is based on the Relaxing Total Variation Diminishing (RTVD) scheme (Jin & Xin 1995). The original scheme (see Trac & Pen 2003 and Pen et al.  2003) has been extended by an addition of dynamically independent, but interacting fluids: dust and a diffusive cosmic ray (CR) gas, described within the fluid approximation, with an option to add other fluids in an easy way. The code has been equipped with shearing-box boundary conditions, a selfgravity module, an Ohmic resistivity module, as well as other facilities which are useful in astrophysical fluid-dynamical simulations. The code is parallelized by means of an MPI library. In this paper we introduce a multifluid extension of the RTVD scheme and present a test case of dust migration in a two-fluid disk composed of gas and dust. We demonstrate that due to the difference in azimuthal velocities of gas and dust and the drag force acting on both components, dust drifts towards maxima of the gas pressure distribution.

In the interstellar medium (ISM), PAHs are abundant and also carry most of the dustsurface. They are thus privileged sites for surface reactions such as the formation ofH2. In regions penetrated by UV photons, PAHs loose electrons by thephotoelectric effect and efficiently heat the gas. In more shielded regions, PAH recombineand may carry an important fraction of the cloud electronic charge which plays animportant role in the gas dynamics and chemistry. We review here processes involving PAHswhich control key aspects of the physics of the ISM. We also discuss the correspondingobservational constraints. Most of these processes involve a detailed knowledge of thecharge of PAHs and we therefore review current models in this area. We argue that morelaboratory measurements of the rate of electronic capture on large PAH cations areneeded.

Studies of dust analogs formed from hydrocarbon(CH4, C2H2, C2H4, C2H6) and PAH precursors havebeen performed using a new facility that we have developed to simulate interstellar andcircumstellar processes. The species formed in a plasma are detected,characterized andmonitored in situ with high-sensitivity techniques,which provide bothspectroscopic and ion mass information. From these measurements we derive information onthe nature,the size and the structure of dust particles,as well as a betterunderstanding of the growth and destruction processes of extraterrestrial dust.

Preliminary simulation and optimization studies of the Directional Dark Matter Detector and the Directional Neutron Observer are presented. These studies show that the neutron interaction with the gas-target in these detectors is treated correctly by GEANT4 and that by lowering the pressure, the sensitivity to low-mass WIMP candidates is increased. The use of negative ion drift might allow us to search the WIMP mass region suggested by the results of the non-directional experiments DAMA/LIBRA, CoGeNT and CRESST-II.

Ultra-compact dwarf galaxies (UCDs) are predominatly found in the cores of nearby galaxy clusters. Besides the Fornax and Virgo cluster, UCDs have also been confirmed in the twice as distant Hydra I and Centaurus clusters. Having (nearly) complete samples of UCDs in some of these clusters allows the study of the bulk properties with respect to the environment they are living in. Moreover, the relation of UCDs to other stellar systems in galaxy clusters, like globular clusters and dwarf ellipticals, can be investigated in detail with the present data sets. The general finding is that UCDs seem to be a heterogenous class of objects. Their spatial distribution within the clusters is in between those of globular clusters and dwarf ellipticals. In the colour-magnitude diagram, blue/metal-poor UCDs coincide with the sequence of nuclear star clusters, whereas red/metal-rich UCDs reach to higher masses and might have originated from the amalgamation of massive star cluster complexes in merger or starburst galaxies.