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).

We present the results of the first light of CORONA obtained during the summer campaign 2005 at Dome C. The CORONA experiment uses an automated 14'' antarctized telescope for its remote operation from the Concordia station. The instrument includes an Achromatized Phase Knife Coronagraph (APKC) with no tip-tilt correction. The high contrast long exposure is obtained from image selection among raw short exposures.

The UFFO pathfinder mission will attempt to locate the optical afterglow of a GRB withinseconds of its detection and location by a wide field X-ray imager. It will be mounted onthe Lomonosov spacecraft for launch in 2013 and consists of a coded mask X-ray imager UBATto detect a GRB and estimate a direction vector which will be passed to the SMT opticalsystem which will rotate a moveable mirror to lock onto the GRB and direct the opticalafterglow to a camera with a  ~17′ wide aperture. We present the design geometry ofthe UBAT instrument only, with results of simulations for a range of GRB types to showprobable photon integration times to be expected to extract a significant FOV imagereconstruction and GRB location.

ALMA will observe extrasolar planetary systems in various stages of formation. From young, planet-forming (protoplanetary), dusty disks, to mature solar-system analogs, ALMA will produce transformational science. We investigate the imaging capabilities of ALMA to infer structure in protoplanetary disks created by a protoplanet, as well as possible direct detection of the protoplanet itself. In addition, ALMA will be able to perform high-accuracy astrometry of main sequence stars, allowing us to search for the astrometric wobble caused by orbiting planets.

The cooling of baryons in the centers of dark matter halos leads to a more concentrated dark matter distribution. This effect has traditionally been calculated using the model of adiabatic contraction, which assumes spherical symmetry, while in hierarchical formation scenarios halos grow via multiple violent mergers. We test the adiabatic contraction model in high-resolution cosmological simulations and find that the dissipation of gas indeed increases the density of dark matter and steepens its radial profile compared to the case without cooling. Although the standard model systematically overpredicts the increase of dark matter density, a simple modification of the assumed invariant from M(r)r to $M(\bar{r})r$, where $\bar{r}$ is the orbit-averaged particle position, reproduces the simulated profiles within 10%.

In this contribution we briefly introduce a mechanism for short gamma ray burst emissiondifferent from the usually assumed compact objects binary merger progenitor model. It isbased on the energy release in the central regions of neutron stars. This energy injectionmay be due to internal self-annihilation of dark matter gravitationally accreted from thegalactic halo. We explain how this effect may trigger its full or partial conversion intoa quark star and, in such a case, induce a gamma ray burst with isotropic equivalentenergies in agreement with those measured experimentally. Additionally, we show how theejection of the outer crust in such events may be accelerated enough to produce Lorentzfactors over those required for gamma ray emission.

Many multi-planet systems have been discovered in recent years. Some of them are in mean-motion resonances (MMR). Planet formation theory was successful in explaining the formation of 2:1, 3:1 and other low resonances as a result of convergent migration. However, higher order resonances require high initial orbital eccentricities in order to be formed by this process and these are in general unexpected in a dissipative disk. We present a way of generating large initial eccentricities using additional planets. This precedure allows us to form high order MMRs and predict new planets using a genetic N-body code.

Late-type MS stars display optical variability on different time scales due to the presence of photospheric brightness inhomogeneities produced by surface magnetic fields, analogous to cool spots and bright faculae observed in the Sun. We are developing methods to model the optical variability of main-sequence late-type stars to understand the impact of solar-like activity on the detection of planetary transits and to significantly improve the detection efficiency. Our techniques will also allow to map the longitude distribution of active regions on stars that harbor planets and to look for a possible connection between stellar activity and the presence of planets around a star. 


It is shown that the cosmological constant problem inbrane-world is different from the same problem in generalrelativity, essentially because the gauge fields fields contributingto the vacuum energy are confined to the brane-world, but the cosmological term propagates in the bulk. The brane-wrld equations of motioninclude a second order, conserved symmetric tensor field infour dimensions defined by the extrinsic curvature, whichadjusts the vacuum energy. In the application to theFRW brane-world universe embedded in a five-dimensional deSitterbulk, that tensor modifies Friedman's equation with a remarkable agreement with the current gold set of cosmological data.

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.

We review recent examples where the synergy between radio and X-ray observations has led to substantial progress in understanding astronomical systems. The sub-arcsecond imaging capabilities of the Chandra X-ray observatory provides a 100-fold improvement for comparing X-ray and radio structures. We specifically discuss examples which provide insight into the outflow of material and energy from pulsars and supernovae, the centers of clusters of galaxies, and the nuclei of quasars.

In the last years, some issues concerning Cepheids have beenresolved, based on observations and modeling. However, as usual, newdifficulties arise. The link between the dynamical structure ofCepheid atmosphere and the distance scale calibration in theuniverse is now clearly established. To support observations, wecurrently need fully consistent hydrodynamical models, includingpulsating and evolutionary theories, convective energy transport,adaptive numerical meshes, and a refined calculation of theradiative transfer within the pulsating atmosphere, and also in theexpected circumstellar envelope (hereafter CSE). Confronting suchmodels with observations (spectral line profiles, spatial- andspectral- visibility curves), will permit to resolve and/orstrengthen subtle questions concerning (1) the limb-darkening, (2)the dynamical structure of Cepheids' atmosphere, (3) the expectedinteraction between the atmosphere and the CSE, and (4) it willbring new insights in determining the fundamental parameters ofCepheids. All these physical quantities are supposed furthermore tobe linked to the pulsation period of Cepheids. From these studies,it will be possible to paint a glowing picture of all Cepheidswithin the instability strip, allowing an unprecedent calibration ofthe period-luminosity relation (hereafter PL relation),leading to new insights in the fields of extragalactic distancescales and cosmology.

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.

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.

The role of Venus and Mercury transits is crucial to know the past history of the solar diameter. Through the W parameter, the logarithmic derivative of the radius with respect to the luminosity, the past values of the solar luminosity can be recovered. The black drop phenomenon affects the evaluation of the instants of internal and external contacts between the planetary disk and the solar limb. With these observed instants compared with the ephemerides the value of the solar diameter is recovered. The black drop and seeing effects are overcome with two fitting circles, to Venus and to the Sun, drawn in the undistorted part of the image. The corrections of ephemerides due to the atmospheric refraction will also be taken into account. The forthcoming transit of Venus will allow an accuracy on the diameter of the Sun better than 0.01 arcsec, with good images of the ingress and of the egress taken each second. Chinese solar observatories are in the optimal conditions to obtain valuable data for the measurement of the solar diameter with the Venus transit of 5/6 June 2012 with an unprecedented accuracy, and with absolute calibration given by the ephemerides.

Red supergiants (RSG) are a crucial phase in the evolution of massive stars. At solar metallicity, they represent the stage where substantial amounts of mass and angular momentum are lost. Here we investigate the role of RSGs at very low metallicity. We have computed evolutionary tracks at Z=0.0004 with and without rotation, using the latest version of the Geneva stellar evolution code. Here, we briefly discuss the evolution of RSGs, their lifetimes, mass ranges for forming RSGs, maximum luminosity of RSGs, and how these are affected by rotation.

The Sculptor dwarf Spheroidal is a Milky Way satellite with a dominant old (>10 Gyr) population that displays at least two distinct stellar populations. We present new sensitive imaging data from CTIO/MOSAIC and make a detailed study of the stellar populations of Sculptor, including the main sequence turnoff (MSTO) properties. We present the Star Formation History (SFH) and Metallicity Distribution Function (MDF) of the Sculptor dSph and find that a well-defined radial gradient is present not only in metallicity but now also in age.

Binary stars are abundant. We describe their orbits and the effects oftides and introduce the concept of the Roche lobe and mass transfer.We illustrate binary star evolution with Algols, cataclysmic variablesand type Ia supernovae as examples.

Chemodynamical disc galaxy simulations coupled with stellar populations synthesis models allow to build multi-wavelength images from numerical simulations, and then to follow their morphological evolution in colour and not only on the mass distribution. Using such technique, we present the evolution of several photometric observables, of the Tully-Fisher relation, as well as the evolution of disc structural parameters.

We have analyzed the distributions of CO and temperature in a large suite of simulatedmolecular clouds, in order to help us understand how to interpret CO line emission fromreal molecular clouds. We find that most of the CO is located at densities over103cm-3 where the temperature is roughly 10–20 K independently ofthe mean density, metallicity and UV field strength. Although, most of the volume is inwarmer and thinner regions where CO abundance is small. On that account, CO observationsalone give a misleading view of the physical conditions in the clouds.