"The different paths of disk dispersal: a Herschel view on young and evolved clusters"

Aurora Sicilia-Aguilar (Universidad Autonoma de Madrid)

Abstract
The short lifetime of protoplanetary disks poses strong constraints to the formation of planetary systems - but fully dispersing a massive disk in a short time can also be a problem. Multiwavelength observations reveal a large variety of disks in clusters of any age, ranging from diskless stars in young regions, to rare disks with strong accretion and little evidence of evolution at 10 Myr. Objects found to be in an intermediate state between disked and diskless systems (transition disks) show also differences in disk structure and accretion properties. In this context, Herschel/PACS observations offer important information on the disk global properties and also on the structure of the star-forming cloud. Exploring with PACS different types of disks in very different clusters (the young Coronet cluster, the intermediate-aged Tr37, and the old NGC7160 cluster), we find a large variety of dispersing disks. Some systems appear to have inner holes and large disk masses, while others have very reduced dust masses and no holes, defining several distinct evolutionary paths. Why some disks disperse at an early age while others continue to accrete for a long time until they evolve in different ways seems to be an interplay of various physical processes where the system's initial conditions and environment probably play an important role.

"Star Formation Rates and Scaling Relations in Molecular Clouds"

Marco Lombardi (University of Milan)

Abstract
It has long been recognized that star formation occurs in dark molecular clouds, but the physical properties of these objects and the star formation process is still largely debated. In this talk I will present recent investigations on the structure of molecular clouds and on scaling relations between star formation rates and molecular gas masses. To obtain these results I correlate near-infrared extinction maps of a set of nearby molecular clouds with catalogues of protostars observed in the clouds. With these data in hand I will show that there is a local equivalent of the Kennicutt-Schmidt law for star formation.

"Neutron stars in globular clusters: catch and lose"

Frank Verbunt (Radboud Universiteit 
Nijmegen)

Abstract
Millisecond radio pulsars are abundant in globular clusters, as are their progenitors, the X-ray binaries. They are formed in close encounters between neutron stars and other stars and binaries, as realized soon after their discovery. A binary with a neutron star formed by a close encounter is in turn subject to further, secondary encounters. I describe my research with Paulo Freire (MPI f. Radioastronomie, Bonn) on possible relations between such secondary encounters and the observed properties of radio pulsars in globular clusters, and on a possible explanation for apparently young pulsars among them.

"Sailors, 
astronomers and the discovery of the southern sky"

Frank Verbunt (Radboud Universiteit 
Nijmegen)

Abstract
The area around the southern celestial pole is invisible from Europe, and was therefore unknown to European astronomers until seafarers started traveling the southern seas after1500. The first detailed maps of the previously invisible area was made on the basis of measurements made by Dirck Keyser and Frederick de Houtman, during and after the first merchant voyage of Dutchmen to the Far East.

The talk describes the adventures accompanying the measurements, the controversy concerning priority, the grouping of the newly found stars in twelve constellations, and the spread of this knowledge across Europe in the form of globes, maps and catalogues. The talk ends discussing Halley’s accurate measurements on the island of St.Helena.

"The detailed view of the interplay of gas and stars in starburst galaxies: NGC 5253 as a case sample"

Ana Monreal-Ibero (IAA-CSIC, Granada)

Abstract
Nearby blue compact galaxies are a subgroup of starbursts that constitute ideal laboratories to test in detail the interplay between massive star formation and the surrounding gas, under similar conditions to those occurring when galaxies were forming. Given its proximity and the wealth of ancillary information available in all spectral ranges, a particularly well-suited example for the study of this interaction is NGC 5253.

We are carrying out a detailed analysis of the central region of NGC 5253 using optical integral field spectroscopy. The outcome of this work has been published in Monreal-Ibero et al. 2010, 2012, 2013 and Westmoquette et al. 2013. In this talk I will review the results presented so far. Among other topics, I will address the 3D structure of the physical properties (electron density, temperature and excitation) of the ionized gas. Also, I will present mapping of its chemical content and the relation with the Wolf-Rayet star population of this galaxy. Two elements, deserving a detailed discussion, will be highlighted: nitrogen and helium.

"Epic Astrobiology"

Caleb Scharf

Abstract
The study of life, its origins, forms, and possible presence beyond the Earth is experiencing a renaissance. Much of this is driven by discoveries here, on Mars and in our solar system, and especially in the abundant and diverse population of planets around other stars. I will review some of the more interesting pieces of science, and discuss the theoretical and observational challenges that are particular for astronomy, as well as ways in which we're making progress and what we can expect from this odyssey in the near future.

"Towards a more comprehensive understanding of exo-planetary worlds with direct imaging"

Laurent Pueyo (STScI)

Abstract
Direct imaging mitigates selection effects inherent to the currently known exo-planetary population since it is sensitive to objects in an orbital space orthogonal to the one available with indirect methods. Upcoming campaigns will survey young and adolescent stars and probe for signatures of their formation history using instruments designed for high-contrast imaging. In the first part of this presentation I will discuss the wealth of information accessible using such surveys. I will describe current methods and ongoing projects aimed not only at identifying exo-planetary systems but also at estimating their bulk physical properties and atmospheric chemistry. I will in particular highlight our recents results, obtained using both the HST NICMOS Archive and the Project 1640 Integral Field Spectrograph installed at the Palomar Hale Telescope, that provide new insights regarding the true nature of a known exo-planetary system. Direct imaging is moreover envisioned as the preferred method to search for biomarkers in the atmosphere of earth-analogs, and answer one of humanity's most ancient questions "Are we alone?". This endeavor presents daunting technical challenges: such science requires to detect a planet whose signal is ten order of magnitude fainter than its host star. In the second part of this presentation I will review recent progress in high-contrast coronagraphic technologies spurred by this ambitious goal, with a particular emphasis on our work in high-precision modeling and experimental demonstration of phase induced amplitude modulation concepts. Technology demonstration efforts in this field have been focused on un-obscured off-axis apertures, because of the long standing belief that light diffracted by the secondary support structures and segment gaps would be a major hindrance to reaching the desired contrast. This places considerable constraints on future observatory architectures. I will present a solution to this problem and show that, using concepts and technologies already developed for monolithic un-obscured telescopes, high-contrast can in principle be achieved with any aperture geometry, even in the presence of a central obscuration and segment gaps.