Seminars and Colloquia at ESO Santiago

I will present QSFit, a new software package able to perform automatic analysis of Active Galactic Nuclei (AGN) optical spectra. The software provides luminosity estimates for the AGN continuum, the Balmer continuum, both optical and UV iron blended complex, host galaxy and emission lines, as well as widths, velocity offsets and equivalent widths of emission lines, and slopes of the AGN continuum.

We used QSFit to analyze 71,251 SDSS optical spectra of Type 1 AGN at z < 2 and to produce a publicly available catalog of AGN spectral properties. Such catalog allowed us (for the first time) to estimate the AGN continuum slopes and the Balmer continuum luminosities on a very large sample, and to show that there is no evident correlation between the continuum slopes and the redshift. All data in the catalog and the IDL code to replicate the analysis, are available in a dedicated website.

The whole fitting process is customizable for specific needs, and can be extended to analyze spectra from other data sources. The ultimate purpose of QSFit is to allow astronomers to run standardized recipes to analyze the AGN data, in a simple, replicable and shareable way.

The Dark Energy Survey (DES) supernova program has completed the 4 of its 5 years of observations. This multi-colour, cadenced search for high redshift supernova has already discovered over 1500 likely type Ia supernova (SNIa) candidates. With NIR light-curves, spectroscopy and deep stacks providing photometric redshifts and detailed environmental information for every transient, the DES dataset is unrivalled in it's potential to to study SLSNe. I will present the DES SLSN sample from the first 4 years of the survey, including the highest spectroscopically confirmed supernova at z~2.

Multiple stellar populations in Milky Way globular clusters manifest themselves in a large variety of photometric sequences in the color-magnitude diagram and chemical patterns. The origin of these patterns is still unknown. According to some scenarios, multiple sequences are the signatures of multiple stellar generations, Milky Way globular clusters were much more massive at their birth and contributed significantly to the assembly of the Galactic halo. I will review the observational evidence of multiple stellar populations in Milky Way globular clusters and present the latest results in the field.

Observation of gravitational waves leave no doubt: black holes are real, gigantic, massive structures made of pure gravity. But our theoretical understanding allows them also to be small, and interact in a very special way with the sub-atomic particles. What do the smallest possible black holes look like? We have no way to observe them, they probably are nowhere close to us, but in principle, they should exist, and we want to understand their laws. Then, they form a fantastic puzzle that our theoreticians are trying to solve. In doing so, we may learn new things about these black holes, about the space and time they sit in, and about those subatomic particles.

In the seventh session of the JAO series on Practical Interferometry, we continue with topics related to imaging.  This session will focus on multi-resolution ALMA data, meaning data from two or more of the following: 12-m array, 7m-array, and total power (single dish).  Combining data from the multiple ALMA arrays is a powerful method to recover emission over a range of spatial scales.  We will review various methods, including feather and joint deconvolution.  We will show some specific (molecular outflow) examples using the different methods.

The results from the ALMA polarization system have begun both to expand and to confound our understanding of the role of the magnetic field in low-mass star formation.  After a brief motivation via CARMA, SMA, and other polarization observations from the prior decade, I will discuss new ALMA results, including the highest resolution and highest sensitivity polarization images made to date of two very young, Class 0 protostellar sources.  These new observations achieve ~140 AU resolution, allowing us to probe polarization -- and thus magnetic field orientation -- in the innermost regions surrounding the protostars.  First is a Class 0 protostellar source in Serpens known as Ser-emb 8, where a comparison with cutting-edge, moving-mesh AREPO simulations suggests that cloud-scale turbulence -- not a large-scale magnetic field preserved from the source's natal cloud -- is dictating the magnetic field morphology immediately surrounding the protostar.  In contrast, in the second source, known as Serpens SMM1, the magnetic field has clearly been shaped by the bipolar outflow emanating from the central source -- a situation that is quite different from the turbulence-dominated morphology of Ser-emb 8.  Finally, I will show recent observations of polarization toward IM Lup, a much more evolved, Class II protoplanetary disk.  In the case of IM Lup, consistent with previous observations of other disks, the polarization appears to be due to scattering by dust grains, thus complicating the search for magnetic fields in disks, but opening up a new window into dust grain growth and evolution.

In the past few years the advance of multiplexing spectographs has enabled astronomers to obtain valuable insights into the kinematics of intermediate to high redshift galaxies, with the ultimate goal of discovering a link between the evolution of disks and dark matter haloes. One of the most sought after diagnostics is the stellar mass Tully-Fisher relation, which cosmological dark matter simulations have predicted should have evolved since high redshift (z<3). Analysis of emission line kinematics have provided tentative evidence for this prediction, albeit with large scatter between different studies, especially at z < 1. However the interpretation of such an offset of the Tully-Fisher relation is made more complicated because of the significant role that gas plays in high redshift disks, the sample selections of different surveys, and the lack of signal-to-noise to recover rotation at radii beyond the optical disk. In this talk I will present recent results from the Large Early Galaxy Astrophysics Census (LEGA-C), a VLT/VIMOS survey of ~3000 K-band selected galaxies at 0.6 < z < 1. The high integration times - ~20 hrs per source - provide the signal-to-noise needed to obtain strong constraints not only on the gas kinematics, but also the stellar kinematics of galaxies. I will combine these constraints to derive the Tully-Fisher relation between 0.6 < z <1 as well as constraints on dark matter and baryonic mass.

The predictions of light element abundances in standard Big Bang Nucleosynthesis (BBN) agree very well with astrophysical probes of primordial material, with the exception of lithium.  Most of the observational constraints we have on the primordial abundance and cosmic evolution of Li comes by way of the Li abundance in stellar atmospheres, which  are four times lower than BBN predictions in the precision CMB era.  A broad range of potential solutions to this "lithium problem" have been suggested, from stellar astrophysics solutions (depletion of the surface Li abundances in stars) to physics beyond the Standard Model (annihilating or decaying dark matter in the epoch of BBN).  We have adopted a new approach to this problem, using observations of Li in interstellar gas of low-metallicity galaxies to probe the cosmic evolution of Li.  I will summarize our recent results using this approach, which leave the door open for new physics in the early Universe.

The last few years have seen the advent of new technologies in the sub-mm and IR regimes that allow for unprecedented quality observations of star forming regions. As such we are finally able to produce statistically significant samples of star forming cores at the same time as mapping their surrounding environment with high spatial resolution. In this talk I will present results from the Herschel Space Observatory Gould Belt and HOBYs surveys that covered the Orion A Molecular Cloud complex and the W3 Giant Molecular Cloud. Both these regions contain intermediate to high mass star formation and a rich environment that includes triggered and spontaneous star forming regions as well as a plethora of filaments. We have obtained a statistically significant sample of star forming cores located in different environments and thus derived the properties both of the dense cores as well as their surrounding environment. As such, in this talk I will discuss the role of the environment in deciding the final mass of the forming stars with a focus on the presence of filaments and triggering phenomena in these two star forming regions.

The Fornax Deep Survey (FDS) is a new deep imaging survey of the Fornax Cluster, including thegroup of NGC 1316 (the Radio Galaxy Fornax A), taken with ESO’s VST by a Europeanconsortium with a strong contribution from INAF-Naples (Italy) and Groningen. With data similarin depth to the NGVS survey of Virgo, we are studying many aspects of the formation of galaxiesand the role of the environment. We concentrate on dwarf galaxies, outer halos of massive galaxies,and globular cluster systems around galaxies. Apart from optical data in ugr and i we also have datain the near-infrared K-band, and can use archival surveys in the UV and mid-IR. An HI survey withthe MeerKAT instrument in South Africa is starting soon, and we are undertaking an IFU survey ofa complete sample of dwarf galaxies with SAMI at the AAT. In this talk I will concentrate onstudies of Ultra Diffuse Galaxies (UDGs) in Fornax, and on studies to characterise the dwarfpopulation in nearby clusters.

Astronomical observations are mostly based on measurements of the intensity of light emitted or scattered by celestial objects. Polarimetry is a technique that measures another property of light, i.e., the distribution of the planes of oscillation of the electric field associated to the radiation itself. When this distribution is not uniformly random, we say that the light is polarised.
Polarisation arises every time there is a mechanism that breaks the symmetry within a radiative source, or between the source and the observer, for example the presence of a magnetic field in a stellar atmosphere, or the scattering of the sunlight by the surface of an asteroid. In this talk I will introduce basic concepts and describe some applications of polarimetric techniques both in everyday life and in astronomy. I will present recent spectropolarimetric observations of various objects of our solar system, including planet Earth. I will show how these new measurements represent a serious challenge for our theoretical understanding of the light scattering, but also a powerfull tool for remote sensing, including monitoring of the terrestrial atmosphere, and search for extraterrestrial life.

Luminous infrared galaxies (LIRGs) dominate the cosmic infrared background, and hence their study is crucial to understand galaxy formation and evolution. Furthermore, their extreme environments make them ideal laboratories to probe both star formation, nuclear activity, and the interplay between both phenomena. On this talk I will summarize my work, giving an overview of the main physical processes taking place in local LIRGs from a multi-wavelength perspective at different spatial scales, from their overall properties to their central hundred-parsec regions.

A nova eruption in a cataclysmic variable (CV) is a thermonuclear
explosion on the surface of the white-dwarf primary once it has accreted
a critical mass from its late-type companion. In-between
these eruptions, the binary is supposed to appear as a ’normal’ CV,
although for the fist tens or hundreds of years, the white dwarf is
still heated up which might influence the mass-transfer rate of the
binary. To compare the nova-populations with the general CV-one, a large
number of old novae are needed. We have conducted a program to recover
old novae and study the binary within. I here present the results of
this program as well as of new deep wide-field Hα + [NII] surveys of
cataclysmic variables to search for remnant nova shells around the
binaries. Such shells have been found around some cataclysmic variables
that were hitherto not known as novae. They provide the unambiguous
evidence that the system has experienced a nova eruption in the past and
thus point to the oldest novae observable.

Orion's massive Integral Shaped Filament (ISF) is home to the nearest significant protocluster, the Orion Nebula Cluster (ONC). We compare 3 constituents of Orion A (gas, protostars, and YSOs), both morphologically and kinematically, to show the following. Essentially all protostars lie superposed on the Integral Shaped Filament (ISF), while almost all YSOs are not.  The fact that protostars move <1 kms relative to the filaments, while YSOs move several times faster, implies that a “slingshot mechanism” may eject protostars from the dense filamentary cradle. The B-field morphology (helical) and strength, compared with the gas mass distribution, indicates that magnetic instabilities may be propagating through the cloud, driving oscillations in the ISF. These may be responsible for the "slingshot". Followup ALMA data confirm aspects of this picture.  New work on the Orion Nebula Cluster (ONC) further elucidates the local physical properties in the center of the forming protocluster.  Intriguingly, the ONC crossing time (~0.5 Myr) is nearly identical to the filament oscillation timescale.  These results indicate that the gas density regulates the star density in the ONC, such that tidal effects due to filament oscillations may set the protocluster structure.  We suggest that clusters that form in oscillating filaments are ultimately ejected, similar to the protostars in the "slingshot", thereby ending their formation phase.

Finding life on an exoplanet from telescopic observations would be a historic discovery. But what should we look for? Also, how do we assign a probability to whether life has really been found? Terrestrial life modulates most atmospheric gases so that remote spectra can indicate life. The most unusual gas is O2, which first accumulated 2.4-2.1 Gyr ago. From this time, life would have been remotely detectable from ozone or oxygen bands. Today’s oxidizing air creates transparency to sunlight, allowing prominent Rayleigh scattering, so that even Earth’s visible “Pale Blue Dot” color is biological. But O2-producing metabolism is complex compared to that of simpler life that doesn’t use or produce O2. What, then, is a biosignature on an inhabited world without O2? A more general approach examines how biogenic gases cause chemical disequilibrium. Disequilibrium suggests that relatively abundant CH4 and CO2 in the absence of CO is a combinatorial biosignature on an inhabited, anoxic world. Such a biosignature might be more prevalent than oxygen/ozone and might be detectable with extremely large telescopes or perhaps JWST. But the extraordinary claim of life should be the hypothesis of last resort only after abiotic alternatives are eliminated. Possible false positives suggest the need for a probabilistic framework to assess biosignatures. In such a framework, I argue, the ‘habitable zone’ is a Bayesian prior and appropriate simulations need to find Bayesian likelihoods of spectral or photometric data occurring in scenarios with and without life.

The basic ALMA calibration, imaging and cleaning-deconvolution are first quickly reviewed. The data simulation package in ALMA is then described and used for the planning a relatively complicated ALMA observation at two frequencies and two configurations. Then, these data will be imaged using the new task in casa for image deconvolution, tclean, to illustrate its use.

Condensate clouds are crucial to understand the atmospheric spectra of exoplanets and ultracool brown dwarfs. However, the link between cloud structure and physical parameters like surface gravity remains poorly understood. Under Hubble Space Telescope Cloud Atlas Program (P.I: Daniel Apai), we use rotational modulations to measure cloud structure variation at different atmospheric pressure levels and compare rotational amplitudes across different surface gravity and spectral types objects. In this talk, I will present one of the largest rotational modulation of an unusually red L-dwarf,  WISEP J0047, discuss the latest modeling progress of its atmosphere and it's implication to our current understanding of dusty cloud structure. I will also provide a brief introduction of my current observing program that aims to investigate further the formation mechanism of dusty clouds.

Transmission spectroscopy offers the exciting possibility of studying terrestrial exoplanet atmospheres in the near-term future. The TESS mission, scheduled for launch next year, is expected to discover thousands of transiting exoplanets around bright host stars, including an estimated twenty habitable zone super-Earths. Atmospheric follow-up for the majority of these exciting exoplanets will come from ground-based observations, due to time pressure on space-based facilities. At the same time, unprecedented precisions from both ground- and space-based instruments will enable searches for atmospheric signatures from smaller and cooler exoplanets. However, these observations will be increasingly subject to noise introduced by heterogeneities in the host star photospheres such as star spots and faculae. In this talk, I will discuss ACCESS, the largest ground-based transmission spectroscopy survey to date, and how we are laying the groundwork for atmospheric follow-up of TESS targets. I will also summarize our work on understanding the effects of heterogeneous stellar photospheres on current and future transit observations. The combination of these foundational steps will allow us to successfully identify and correctly interpret exoplanet transmission spectra from exciting TESS targets.

The ESO Library has always served as a substantial information resource
through its collections and ESO telescope bibliography (telbib).
Additionally, the Library shares developments in the evolving fields of
publishing and scholarly communications with our users. This
presentation will focus on the Library's recent efforts in improving its
telbib database and interface; the implementation of DOIs (Digital
Object Identifiers) at ESO; the use of the Zenodo platform for ESO
conference proceedings; and promotion of the ORCID author identifier as
a means of improving research data management.

TBD

The Square Kilometre Array (SKA) will be a next-generation radio telescope. It will be by several measures, the largest scientific facility on Earth. This is an ambitious project to build a radio telescope that will revolutionise our understanding of the Universe and the laws of fundamental physics. This talk will describe the key features and requirements to begin this process by designing and building SKA1 and the benefits that will result.

In the first quarter of 2018, new powerful ways of interacting with the ESO Science Archive
will be offered. On one side, users will be able to search and navigate through the
science data products of ESO using a new, very interactive, and full-sky visual web interface.
On the other, using their own favourite programming language, or via common astronomical tools,
users will gain direct database and data access to the enriched science metadata, and to the
collections of science data and ambient measurements.
A short demo about the new web user interface will be provided,
along with some examples of tool interactions with the archive.
Finally, using the new infrastructure I will demonstrate how it becomes possible
to correlate ambient conditions with the data quality of the science data products.

I will present our analysis results on the mid-J CO line

emission over galaxy scale from a large sample of local

luminous infrared galaxies (LIRGs) observed with Herschel

Space Observatory and the CO (6-5) line emission over

a scale of 30-100 pc in the nuclei of representative

LIRGs observed with ALMA.  The mid-J CO line emission acts

as the cooling mechanism for the dense molecular gas that

is giving birth to and also receiving energetic feedback

from young stars. I will highlight what we have learnt

from these observations with respect to the interplay

between molecular gas, star formation and AGN, and illustrate

how one can apply our local knowledge to characterizing

star formation and gas properties in high-z galaxies.

It is well known that the magnetic activity of solar type stars decreases with age, but it is widely debated in the literature whether there is a smooth decline or if there is an early sharp drop until 1-2 Gyr followed by a relatively inactive constant phase. We revisited the activity-age (AC) relation through Ca II H & K lines. We measure the activity indices using HARPS time-series observations of 82 solar twins with precise isochronal ages and physical parameters. New relations between activity and age of solar twins were derived assessing the chromospheric age-dating limits. The age-activity relation is still statistically significant up to ages around 6-7 Gyr, in agreement with previous works using old open clusters and field stars with precise ages. This confirms that Ca II H & K lines remain a useful clock also for stars slightly older than the Sun.

I will review recent results regarding the evolution of key properties of young solar-type stars during 
the pre-main sequence stage and beyond. I will highlight in particular early rotational evolution and its 
relationship to disk accretion, the evolving magnetic properties of young stars, and the different modes 
of star-disk interaction as recently revealed by space photometry and the follow-up spectroscopic and 
spectropolarimetric monitoring of a few prototypical young stellar objects. 

The interpretation of observational data implies the solution of an ill-posed inverse problem. Bayesian probability theory (BPT) is applied to ensure that the solution is stable, unique and close to the exact solution of the inverse problem. Bayes’ theorem allows us to tackle the problem by means of backward probabilities. The backward probability involves inductive reasoning and it differs from the forward probability. The latter represents the distribution of the experimental data specified by the error distribution of the experiment. The backward probability, instead, does not  describe properties of random variables, though it depends on the full data, on the errors entering the experiment and on all relevant information concerning the nature of the physical situation and knowledge of the experiment. Representative models are incorporated into the analysis with the advantage to provide a simplified description of the complex process for reasoning. BPT provides the tool to investigate probabilistic models and to deal with uncertainties in the data with a principled and defined method. An automated system to reason, i.e. to take information about the world and to reach conclusions, is provided.

Special focus is given on applications to image and spectra analysis, involving the estimation of a (complex) objective function defined in an high-dimensional design domain. BPT applications are shown through MaxEnt method (A.Strong et al., 1989+), Bayesian mixture models (F.Guglielmetti et al., 2009+), Information Field Theory (T.Ensslin et al., 2009+), robust outlier tolerant evaluation (U. von Toussaint et al., 2014+), the axion-search example (F.Beaujean et al., 2017).

You can find more about talks on Bayesian data analysis at:

http://wwwmpa.mpa-garching.mpg.de/~ensslin/Bayes_Forum/bayes_forum.html

Ground-based telescopes equipped with state-of-the-art spectrographs are able to obtain high-resolution transmission and emission spectra of exoplanets that probe the structure and composition of their atmospheres. Various atomic and molecular species, such as Na, CO, H2O have been already detected in a number of hot Jupiters. Molecular species have been observed only in the near-infrared while atomic species have been observed in the visible. I will focus my talk on the search of water vapor in the atmosphere of the exoplanet HD 189733b using a high-resolution transmission spectrum in the visible obtained with HARPS. I am using a cross-correlation technique that combines the signal of 600 - 900 individual water vapor lines in the water band around 6 500 Å. And I would like to show that this technique is able to reach a 1-σ precision of 20 ppm on the transmission spectrum and demonstrate that space-like sensitivity can be achieved from the ground, even for a molecule that is a strong telluric absorber. This approach opens new perspectives to detect various atomic and molecular species with future instruments such as ESPRESSO at the VLT. Upcoming near-IR spectrographs will be even more efficient and sensitive to a wider range of molecular species.

Gaia, the 1+ billion star, highest precision, astrometric satellite mission was launched in December 2013.  This mission is on course to revolutionise our understanding of many areas in astronomyfrom the dynamical and physical properties of minor bodies in our Solar System to the formation andstructure of the Milky Way, and thus of galaxies in general. In order to fully achieve the ambitious goals of the mission, and to completely eliminate systematic influences such as aberration, we must know the position and velocity vectors of the spacecraft as it orbits the Lagrange point to an accuracy greater than can be obtained by traditional radar techniques. For this reason the GBOT-group was formed within the Gaia Data Processing and Analysis Consortium utilising a small network of 2 m class telescopes.Observations are being done on a daily basis, the aim being of a precision/ accuracy of 20 mas.I will given an overview of the project, including the status so far, the turbulent history, and the challenges ahead and will also comment on the GBOT asteroid programme, an extention of the actual GBOT mission, exploiting the GBOT data to search for asteroids that happen to be in the field, almost 14,000 of which have been detected until now.

Low-frequency observations were typical when radioastronomy was born, but soon the interest focused
on the 1-10 GHz range, which became the standard in the field. Recently, new instruments have been
built to observe the sky below 1 GHz. In this talk, I will present the LOw Frequency ARray (LOFAR), 
which operates in Europe with unprecedented sensitivity and angular resolution between 10 and 250 
MHz. I will summarize some scientific results achieved by various groups with LOFAR as well as the 
technical challenges related to operating such an instrument. Besides its role as a pathfinder for SKA,
thanks to its growing network with baselines beyond 1000 km and frequency range down to 10 MHz, 
LOFAR will still play a major role even when SKA1 is fully operational.

According to standard evolutionary theory, cataclysmic variables (CV)
evolve from longer to shorter orbital periods until a minimum period
P_min is reached. The period bouncers are such CVs that have passed
beyond P_min and are evolving back toward longer periods, with the
donor star now extremely dim. This has long been predicted to be the
"graveyard" and current state of 70% of all CVs, though only about a
dozen of more or less robust candidates for such period bouncer
systems have been identified until now, out of a thousand of known
CVs. In this talk I will discuss the various methods by which such
post period-minimum CVs can be recognized, and will also highlight
recent progress in this field.

The NASA “New Frontier” Juno mission has been investigating Jupiter’s 
atmosphere since August 2016, providing unprecedented insights into 
the planet.
Juno includes a suite of 9 instruments, with the aim to investigate 
the Jupiter origin and properties, with a particular attention to the 
magnetosphere, and atmospheric chemistry and dynamics. In addition, 
Juno observations are strongly contributing in disclosing the auroral 
mechanism properties. The spacecraft is in a spinning elliptic polar 
orbit, which makes the observations quite peculiar and innovative to 
achieve the proposed scientific objectives.

The Jupiter Infrared Auroral Mapper (JIRAM) experiment is equipped 
with a single telescope that accommodates both an infrared camera and 
a spectrometer, which permits obtaining images in the L and M bands 
with the spectral radiance over the central zone of the images. JIRAM 
is also able to perform spectral imaging of the planet in the spectral 
range 2.0-5.0 μm covered with 336 bins and a spectral sampling of 9 
nm. Instrument design, modes, and observation strategy are optimized 
for operations onboard a spinning spacecraft in polar orbit around 
Jupiter.

We will present first results obtained with the JIRAM experiment, and 
focusing in particular on the H3+ emissions on both hemisphere of 
Jupiter in the auroral oval and at mid latitudes.
Dynamical, chemical and thermal properties have been deeply faced for 
the Great Red Spot by taking advantage of observations with JIRAM in 
the thermal spectral region around 5 μm (Grassi et al. 2017; Sindoni 
et al. 2017). H3+ emissions were investigated both in the auroral 
regions (Dinelli et al., 2017; Adriani et al., 2017; Mura et al., 
2017) and at mid latitudes (Migliorini et al., in preparation).

The JIRAM heritage comes from Italian-made, visual-infrared imaging 
spectrometers dedicated to planetary exploration, such as VIMS-V on 
Cassini, VIRTIS on Rosetta and Venus Express, and VIR-MS on the Dawn 
mission.

In this talk, I will present a new extragalactic survey that characterise dusty galaxies at low redshifts: the Valparaíso ALMA Line Emission Survey (VALES). I will introduce the use of ALMA Band-3 CO(1-0) and APEX SEPIA Band-5 CO(2-1) observations to study the molecular gas content in a sample of ~100 main-sequence (and starburst) star forming galaxies up to z=0.35. The galaxies are far-IR bright [L_IR/Lo = 10^(10-12)Lo] emitters selected from the H-ATLAS survey over ∼160 deg^2 and present good wavelength coverage. We have spectrally detected (>5sigma in a previous Herschel campaign) 27 galaxies in [CII] and ~60 galaxies in CO, facilitating a characterisation of the ISM state in some of these galaxies via Photo Dissociation Region modelling. One third of the ALMA targets are spatially resolved in CO, so we have compared the VALES sample with others taken from the literature in terms of the global Schmidt-Kennicutt law. We are also modelling the dynamics of resolved galaxies in order to understand the main internal parameters controlling the star-formation activity. We explore the star formation efficiency in these galaxies, finding that most of them follow a long-standing mode of star-formation with gas consumption timescales of ~1-2 Gyr. A non negligible fraction of galaxies is found to be dominated by the gas mass content (f_gas>30%), fractions which are similar to those found in normal high-redshift star-forming galaxies. To finalise, I will show the future prospects of this campaign by introducing the follow-up campaigns we are leading from Valparaíso.

References:

http://adsabs.harvard.edu/abs/2017arXiv170509826V

http://adsabs.harvard.edu/abs/2016arXiv161105867H

http://adsabs.harvard.edu/abs/2017arXiv170207350H

The star-formation conditions that produce bound clusters is an important open question. We address this problem in a study of NGC 6231, a young stellar cluster in the Sco OB1 association where star-formation has recently ended. Our study is based on a new, multi-wavelength census of cluster members, which we use to model the cluster’s physical structure. The cluster is well described by an isothermal ellipsoid surface density, with a moderate ellipticity, a cluster core radius of 1.2±0.2 pc, and a central density of 150±50 stars pc^-3. We find mild mass segregation of stars >8 Msun and no radial-age gradient. Substructure includes a small subcluster superimposed on the main cluster as well as non-isotropic structure in the outer regions. Based on these results, we argue that the cluster likely formed through the coalescence of several subclusters of stars, but has expanded significantly since formation. Cluster properties are consistent with NGC 6231 surviving to become a gravitationally bound open cluster like the Pleiades after 100 Myr.

The GaLAxy Cluster Evolution Survey (GLACE) is conducting a thorough study on the variation of galaxy properties (star formation, AGN activity and morphology) as a function of environment in a representative and well-studied sample of clusters, in order to help understanding how galaxy properties are altered as they enter into over-dense

regions. The GLACE survey is performing a deep panoramic survey of emission line galaxies (ELG), mapping a set of optical lines ([OII], [OIII], Hβ and Hα/[NII] when possible) in several galaxy clusters at z ∼ 0.40, 0.63 and 0.86, using the tunable filters (TF) of the OSIRIS instrument at Spanish 10.4m GTC telescope, applying the technique of TF tomography to

cover a range of several thousand km/s within the whole field of view of 8 arcmin.  Multi-wavelength ancillary data (from UV to FIR) are also exploited. In this talk, I will give an overview of the survey, outline the specific techniques applied, in particular those devised to observe and analyse TF data and finally will summarise the main results obtained so far.

Stellar clusters have traditionally been thought of as simple stellar populations, with all of the stars within a given cluster having the same chemical composition and age, within some small tolerance. However, all old globular clusters (GCs) in the Galaxy that have been studied in the necessary detail show chemical abundance anomalies (known as multiple populations - MPs) not observed in field stars of the same metallicity. The most common of these are the Na-O and N-C abundance anti-correlations.
The origin of MPs is still under debate, with none of the proposed scenarios able to reproduce the main observational properties of MPs without making ad hoc assumptions.
I will present the results from our ongoing HST Magellanic Cloud Cluster survey, which attempts to shed light on the physical property that controls the onset of MPs. The survey is composed of 12 massive clusters in the Large and Small Magellanic Clouds, spanning a wide range of ages (100 Myr-11 Gyr), but with similar masses. The surprising result we found is that all clusters older than 2 Gyr appear to host MPs, while all clusters younger do not. This finding clearly marks cluster age as one of the major parameter controlling the presence of MPs. This also points towards a fresh new perspective on to the onset of MPs, since this is completely unexpected for all theories for the origin of MPs.

Galaxies are expected to loose their baryons from galactic winds and acquire new fresh material from the intergalactic medium. How much gas is being lost is an outstanding question in observational cosmology. Thanks to the MUSE VLT instrument, one can now put new constraints on gas flows around galaxies using absorption or emission techniques. In this talk, I will present recent results from the MUSE gto program on the circum-galactic medium.

A new class of supernovae, called superluminous supernovae, has been discovered in the past few years. They are 100 times brighter (with absolute mag -21) than normal core-collapse supernovae. This means that the standard paradigm of iron-core collapse cannot account for the origin of superluminous supernovae. An alternative mechanism is needed to power such high luminosities, such as magnetar spin down, pair-instability explosions or shell collisions. In this talk, I will present our work on superluminous supernovae, from their discovery using all-sky surveys (e.g. PanSTARRS1), to their classification with the Public ESO Spectroscopic Survey for Transient Objects (PESSTO), and their follow-up with large facilities such as the 8m VLT. We found superluminous supernovae appear to occur exclusively in metal-poor dwarf galaxies, indicating that a sub-solar metallicity is required to produce them. We also found a possible relation that, if magnetar powering is the source of the extreme luminosity, the initial magnetar spin is correlated with the metallicity of the host galaxy. If this correlation is found to hold, it represents a major step forward in our understanding of superluminous supernovae. Finally, I will discuss the ongoing and future science projects related to these explosions, in particular utilising JWST and LSST in the next era of high-redshift observations.

The Universe is in constant change. Events such as supernovae and flares from active galactic nuclei give evidence of the transient nature of the sky. Transients are typically discovered by optical surveys observing large regions of the sky at a high cadence. There is however an interest in detecting and studying the counterparts at different wavelengths in order to construct a more complete picture of the transient itself as well as from the object that gave origin to it. In this talk I will present a selection of transients we have followed-up in radio, including recent results on two interesting transients discovered by the All-Sky Automated Survey for Supernovae (ASAS-SN). I will also make a quick review on what can be done with current facilities and how transient radio studies will change when the Square Kilometre Array comes online.

There are two intriguing questions that need to be answered
with future cosmological observations: (1) what sources reionized
the universe and (2) what formation mechanisms are behind the
densest and most ancient stellar systems known today, the Globular
Clusters (GC). These two issues may coalesce into a common answer.
The first point requires the investigation of very low-luminosity
regimes at high redshift, that, in turns, is opening for the
investigation of the second issue (proto-GC). We identified the faintest
star-forming systems at z>3, both in the non-lensed fields (down to
mag_uv~30.5) and behind galaxy clusters (mag_uv~31-33, de-lensed).
The combination of VLT/MUSE/X-Shooter and HST Frontier Fields suggests
some of them are optically thin, powered by young and dense star clusters
having stellar masses of a few 10^6 Msun enclosed within a few tens
parsec effective radius. A new low-luminosity/mass/size regime has been
definitely accessed at z>3, including cases of faint HST-undetected objects.
These new low-luminosity sources will be reference targets for the future
observational campaigns with JWST.

Observations probing the edges of the visible Universe is one of the most intriguing challenges of the coming decade, particularly with respect to detecting the first galaxies at z>12 and the first population III stars. Many surveys have been completed in order to push even further the observational limits of the Universe and to strongly increase the number of very high-redshift sources known (z>6). All these observations aim to constrain the role played by the first galaxies in the reionization process occurring during the first billion years of the Universe. This goal can only be achieved by combining telescopes observing at different wavelength (visible, NIR, IR, sub-mm and radio). After describing the method used to select very distant galaxies, I will demonstrate that the VLT and ALMA are currently the best observatories to determine the nature and physical properties of the most distant galaxies.

In this talk, I will discuss how spectroscopic observations of the chemical components of protoplanetary disks are allowing us to study the structure and chemistry of planet-forming environments, and to test our ideas about how initial conditions and early evolutionary processes influence the outcomes of planet formation.  I will discuss the incredible progress that has been made in this field in the past decade, the challenges that remain, and some of the exciting possibilities for the near and far future.  I will also discuss in some detail an ongoing large program using the VISIR instrument at the VLT - my reason for visiting Chile.

I will present some of the most important results from GASP, a large MUSE program dedicated to studying galaxies undergoing ram-pressure stripping in clusters, commonly known as "jellyfish" galaxies. In particular, I will show some of the most spectacular specimens collected by GASP so far, discuss the orbital histories of jellyfish galaxies in clusters, and present a new exciting discovery that links intense ram-pressure stripping in cluster galaxies with AGN activity.

The observational knowledge of the formation and evolution of galaxies rests heavily
on the ability to perform a complete, or representative, census of all galaxies,
their content in stars, gas, dust and dark matter, at all epochs, a formidable endeavor.
Spectroscopic galaxy surveys are designed to observe the large samples needed
for statistical accuracy, study the distribution of galaxies in space with velocity information
(redshift), and to perform spectral analysis informing of their content.

Over its 15y lifetime, VIMOS on the VLT has been used to constantly pushed the observational
limit, delivering over half a million spectra of galaxies from the nearby universe
all the way to the epoch of reionisation.
I will recall the main science questions that VIMOS is set to answer.
I will then review some of the major VIMOS achievements in the field of galaxy evolution,
with results from the VVDS, zCOSMOS, VIPERS and VUDS surveys, and will present the
on-going LegaC and VANDELS surveys.
With VIMOS set to retire in 2018, I will place the scientific production of VIMOS in
the general context of the VLT, and will give a look to the future of large galaxy surveys.

The study of exoplanet atmospheres has developed rapidly over the last few years, we are now reaching a point where enough hot jupiter atmospheres have been studied in detail that we can begin to perform comparative planetology to figure out the underlying processes.

WASP-52b is a low density Hot jupiter with a particularly high transmission signal that makes it an excellent target for transmission spectroscopy. Using ACAM on the WHT we recovered a transmission spectrum between 400 and 900 nm on two separate nights. A Gaussian Process method was used to remove common mode systematics. Despite having a similar radiation environment to HD 189733b, WASP-52b presents a very different transmission spectrum, hinting at the complexity and variety of planetary atmospheres.

Secondly, I will show that high resolution spectroscopy present an opportunity to spatially resolve the atmospheres of exoplanets. I will present evidence that the atmosphere of the hot Jupiter HD 189733b has a strong eastward motion, with red-shifted absorption detected on the leading limb of the planet and blue-shifted absorption on the trailing limb. The results are based on a time-resolved model of the sodium transmission spectrum measured with the HARPS spectrograph. Our results demonstrate the feasibility of studying the weather patterns of distant planets from the ground.

Water fountain (WF) nebulae are Galactic stellar sources that display large-scale bipolar outflows in their dusty and molecular-rich circumstellar envelopes (CSEs). Such outflows are traced by high-velocity (> 100 km/s) spectral features of H2O maser emission. Moreover, it is thought that WF nebulae are evolved sources transitioning between the Asymptotic giant branch (AGB) phase and the Planetary nebulae (PNe) phase. Therefore, observational studies of the high-velocity outflows can provide important clues about the mechanism, yet unknown, that shapes the aspherical CSEs commonly observed towards PNe. In this talk I will present results of an observational project that aims to study the gas component of the CSEs of the WF nebulae IRAS 18043-2116 and IRAS 15445-5449. The goal of the project is to constrain the spatial distribution of emission from different molecular species at centimeter and micrometer wavelengths. The sources were observed using  the Australia Telescope Compact Array (ATCA), the Jansky Very Large Array (JVLA), and the Very Large Telescope (VLT-SINFONI). In both cases, our results support a scenario where the main energy input for the dynamics of the large-scale bipolar outflows could be associated to the launching and propagation of thermal radio jets throughout the slower, steady-expanding CSEs of these sources.

So far the gas conditions in main-sequence galaxies at the peak of the cosmic star formation history have been mainly investigated through the CO emission lines. However, observing the CO transitions at higher redshift becomes challenging, since the lines luminosity weaken as metallicity decreases. A powerful alternative could be the [CII] emission at 158um instead: it is the brightest line in the radio and far IR regime observed in star-forming galaxies, it is the main coolant of the interstellar medium (ISM), and it does not seem to fade at low metallicity. Local studies show that the [CII] luminosity correlates with the galaxy star formation rate (SFR), although main-sequence sources and starbursts seem to have different behaviours. At higher redshift the picture is even less clear and only samples of starbursts have been analyzed so far. To remedy this situation we have observed with ALMA a sample of ~ 10 main-sequence sources at z ~ 2 with the aim of tackling the following questions: is [CII] a good tracer of the molecular gas? How does it depend on the galaxy physical properties (e.g. SFR, hardness of radiation field, dust temperature and mass, specific SFR)? Answering these questions for z ~ 2 galaxies whose physical conditions are nowadays reasonably well understood will lay the ground for future explorations of the ISM at much higher redshift.

Dust thermal emissions observed with Herschel Space Observatory have revealed that interstellar molecular clouds consist of many filaments.  Polarization observation of interstellar extinctions in the optical and near IR wavelengths shows that the dense filaments are extending perpendicular to the interstellar magnetic field.  Magnetohydrostatic structures of such filaments are studied.  It is well known that a hydrostatic filament without magnetic field has a maximum line mass of lambda_max=2c_s^2/G, where c_s and G represent the isothermal sound speed and the gravitational constant. On the other hand, the magnetically-supported maximum line mass increases in proportion to the magnetic flux per unit length threading the filament (phi), as lambda_max ~ 2c_s^2/G + phi/(2pi G^1/2).  Comparison is made with 3D clouds. Stability of these magnetized filaments is studied using time-dependent 3D MHD simulations to discuss star formation in the filaments.  Polarization pattern expected for the magnetically subcritical filaments is calculated. The distribution function of the angle between B-field and the axis of the filament, which is obtained with Planck Satellite, is compared with this mock observations.

I will report on our recent MUSE observations of bright gravitational arcs to map the spatial distribution of the z=1 CGM. I will discuss our results and argue that this technique opens a new window in absorption-line studies of the high-redshift universe.

In the sixth session of the JAO series on Practical Interferometry, we discuss more advanced topics of calibration.  This follows the March and April presentations on data calibration.  Presentation will be given by expert visitor to the JAO, Luke Maud.  Topics covered will include:

• Phases,
• causes of phase defects,
• B2B study performed along with Yoshiharu Asaki

I will present VANDELS, an ESO public survey already half way to the end. Within VANDELS, we 
started a project dedicated to the definition of the environment and the study of the properties 
of star-forming galaxies in different environments. During my time here at ESO, we searched for 
overdensity structures in the most updated photometric+spectroscopic VANDELS parent catalog. 
I will show the interesting structures we have found at z>2. Also, we focused on a sample of 
Lya emitters and Lya absorbers. We studied their spectroscopic and morphological properties 
with respect to environments of different density. I will present our results on this topic and the 
future plans.

In the fifth session of the JAO series on Practical Interferometry, we discuss imaging.  Topics covered will include:

• Visibility to brightness distribution
• Sampling in (u,v) plane
• Deconvolution
• How to image in channel, frequency and velocity.
• Alternatives to CLEAN
• Imaging artifacts

X-ray luminous galaxy clusters are important probes to trace
the evolution of the cosmic large-scale structure and to test
cosmological models. To perform such studies it is of prime
importance to understand the physical structure of the X-ray
emitting intracluster medium and the scaling relations of
its properties. We will review some of the latest achievements
to constrain cosmological model parameters and neutrino masses
with our REFLEX galaxy cluster survey and discuss the influence
of the properties of the intracluster medium on these results.
Based on our X-ray cluster surveys we compiled a new sample
of superclusters applying a physically motivated definition
of these objects. We review some of the supercluster properties
and discuss how the supercluster environment affects the cluster
properties and its intracluster medium.

Stars are formed in cold and dense molecular clouds by gravitational collapse. This big picture has well been drawn in the past few decades.  However, many details are little known. One of long-standing,fundamental questions in star formation is what the roles of magnetic fields are. Due to the observational capabilities recently dramatically improved, magnetic field studies have the best opportunities ever. In this talk, I will introduce a JCMT large program: the B-fields in star-forming regions (BISTRO) project, which studies magnetic fields toward 16 fields of 7 nearby molecular clouds in intermediate scales.  In addition, I will present my recent ALMA observations toward the youngest protostellar systems, which show the magnetic fields in small scales associated in star formation.

The Antennae galaxies (NGC 4038/39) have long been regarded as the
prototype of a major merger.
In our MUSE data of the central field, we found diffuse Halpha emission
out to the edge of our field, about 15% more than was detected in
existing data. A region around the tip of the southern tidal tail also
shows new detections of both compact and diffuse ionized gas.
Using HST cluster data and MUSE HII region measurements, we investigate
which fraction of the diffuse gas can be ionized by leaking
Lyman-continuum photons from the star formation sites and how these
escape fractions compare to ionization-parameter sensitive line ratios.

There has recently been a large body of work investigating the low-mass end of the stellar initial mass function (IMF) in nearby elliptical galaxies. Usually assumed to be universal between all star forming regions, evidence is now emerging that the IMF may vary from one galaxy to another, or even vary spatially inside a single object. Measuring and understanding such IMF variation, and its consequences for our theories of how both stars and galaxies form, is a technically challenging task for observers and theorists alike. I will discuss how optical and near IR spectra can be used to measure the IMF in nearby galaxies, give some background of the history of this technique and also present results from my own work on this topic.

I will present the results on the project I worked on during my stay at ESO-Santiago. The 
project makes use of VANDELS data. First, we defined the environment in VANDELS. We 
recovered structures known at z<2.5 and we searched for overdensity at higher redshift. 
Also, we studied the spectroscopic properties of the galaxies characterized by a strong 
Lya emission in VANDELS spectra. We then studied similarities and differences on the 
Lyman alpha emission of the Lyman alpha emitters located in overdensities, 
underdensities, and very under dense regions.

The outer Galaxy provides a good opportunity to study star formation in an environment significantly different from that in the solar neighborhood including lower gas density and lower metallicity. However, star-forming regions in the outer Galaxy have never been comprehensively studied or catalogued because of the difficulties in detecting them at such large distance. We searched for star-forming regions with WISE MIR all-sky survey data and FCRAO CO northern outer Galaxy survey data. As a result, we successfully identified 711 new candidate star-forming regions in 240 molecular clouds up to Rg ~ 20 kpc, which enable statistical studies of star formation activities up to the extreme outer Galaxy for the first time. Using the new identified star-forming regions, I will report the global properties of star-formation activities in the outer Galaxy. I will also report our new star-forming region survey in the southern outer Galaxy and our future plan.

MUSE — the cosmic time machine" tells the story of the design, manufacture, installation, first light, and commissioning ofMUSE, the Multi-Unit Spectroscopic Explorer. This innovative and extremely powerful instrument, installed on the VLT in 2014, can measure the spectrum of light from every pixel in its images, giving a three-dimensional view of astronomical objects ranging from planets and satellites in the Solar System, through the properties of star-forming regions in the Milky Way and out to the distant Universe. The movie also explains — for a general audience — some of the exciting new science that is being done with this giant and complex machine.

The All-Sky Automated Survey for Supernovae (ASAS-SN or "Assassin") is a long-term project that is using small optical telescopes with wide fields of view to monitor the whole sky at high cadence. ASAS-SN started a real-time search for variable sources in the northern hemisphere in May 2013 and since July 2015 has been using 8 x 14cm robotic telescopes hosted by Las Cumbres Observatory in Haleakala (Hawaii) and Cerro Tololo (Chile) to observe the whole sky down to V ~ 17 mag every 2-3 days. The main scientific goal of ASAS-SN is to find the brightest supernovae without biases to their host galaxy properties. This systematic all-sky search allows ASAS-SN to discover many other interesting Galactic and extragalactic optical transients, including cataclysmic variables, large amplitude M-dwarf flares, young stars in outburst, novae, AGNs in outburst, and tidal disruptions events. In this talk, I will give an overview of the ASAS-SN survey and will highlight some of our most interesting discoveries. I will also discuss our plans for the future (2017-2018) of ASAS-SN: monitoring the whole sky every night and making all the light curves public in real time.

How do the properties of dark halos change with the brightness of the galaxies?  Galaxies of different masses form at different redshifts, so we would expect some changes. We measure the densities and scale radii for the dark halos of spirals from their rotation curves. For the very faint  pressure-supported dwarf galaxies, we can use the structure and velocity dispersions of their stars or gas. It turns out that the dark halos have well defined scaling laws between the brightness of the parent galaxy and the density and scale radii of the dark halos, extending over about 20 magnitudes in brightness. The origin of these scaling laws goes back to the fluctuation spectrum of the early universe. We also conclude that there may be a population of dark dwarfs with circular velocities less than about 40 km/s.

Galaxy rotation curves are an important source of information about the properties of dark halos. To study the dark halos, we need to decompose  the rotation curves into contributions from the baryons and the dark matter. This process is degenerate, unless we know a priori how much of the gravitational field comes from the baryons. It is possible to estimate the mass of the stellar disk directly by measuring the velocity dispersions of the disk stars, but the methods used so far have a basic conceptual flaw. We have tried to find a way around this flaw: our very recent work shows that the gravitational field in the inner parts of spirals is indeed dominated by the stellar disk.

I will discuss the main components of the Milky Way: the thin and thick disks. the bulge, and the stellar halo, the gaseous halo and the dark halo.  Each component is important as part of the narrative about how disk galaxies are assembled and evolve, chemically and dynamically. I will also discuss the implications of recent observations of disk galaxies at high redshift for the assembly narrative.

X-ray binaries are systems formed by either a neutron star or a black hole which is fed by a 'normal' companion star. In particular, transient X-ray binaries --a type of X-ray binaries with low-mass companions showing bright outburst episodes followed by long quiescence states-- are the perfect hunting ground to search for stellar-mass black holes. I will summarise their main properties, observational techniques to unveil them and our main difficulties. I will also present the latest results about Swift J1357.2-0933, V404 Cyg and MAXI J1659-152: systems that are changing our current understanding about these type of binaries.

Surveys of the presence of a magnetic field in components of upper main sequence
binary systems have the potential to uncover the field generation mechanism
and to learn about the impact of the magnetic field on the binary evolution. Due
to the obvious lack of magnetic components in binaries with short orbital
periods, a merging scenario for the origin of Ap stars was suggested. Indeed,
only two close binaries with a magnetic Ap component are currently known.
Importantly, the magnetic field behaviour in these Ap components is closely
related to the position of the companion. Also the inhomogeneous surface element
distribution appears to be affected by the presence of the companion. In our
talk we present the results of our study of a few recently detected
systems with magnetic components and discuss the implication for the origin of
their magnetism.

I will present a large ongoing effort to reveal the evolving structure of planet-forming disks at 0.05-10 au. A major component of this work is based on high-resolution spectroscopy (R ~ 700-100,000) of molecular gas emission at infrared wavelengths (2.9-35 um), as collected from a suite of instruments on the ground and in space (VLT-CRIRES, VLT-VISIR, Spitzer-IRS, Keck-NIRSPEC, IRTF-ISHELL). Large surveys of spectrally-resolved CO and H2O infrared emission from protoplanetary disks are providing spatially-resolved measurements of: 1) the location and excitation of molecules in the 0.05-10 au region, 2) the simultaneous depletion of dust and molecular gas during planet formation, 3) the evolving chemistry of inner disks that are being dried-up from their water content. We are now combining these surveys to high-resolution optical spectroscopy, to understand the role of winds in dispersing inner disks. I will conclude with future prospects for studies of evolving planet-forming disks at 0.05-10 au with upcoming observatories.

Rest-frame ultra-violet emission lines, including the Lyma alpha, CIII] and CIV emission lines, carry a wealth of information about the galaxies they are emitted from. Among other things the redshift, the ionization state, metallicity, and the temperature can be probed with these lines. At the epoch of reionization and shortly thereafter, these quantities are largely unknown. Hence, searching for and detecting rest-frame UV emission lines is a valuable tool to probe the physics governing galaxies at these epochs. I will present the latest results from our rest-frame UV line searches in the near-infrared (z > 6) with the HST Grism Lens-Amplified Survey from Space (GLASS), and in the optical (3 < z < 6) with VLT's Multi Unit Spectroscopic Explorer (MUSE).

TBD

I will aim to summarize the progress made in understanding the AU scale environment near an accreting luminous starover the past decade. Phenomena that occur on milli-arcsecond scales can now be accessed and allow a comparison of the "accretion-ejection" paradigm between high- and low-mass stars. This presentation will focus on observations with results from the VLT interferometer using the instruments AMBER and GRAVITY.

Recent observations from ALMA and extreme AO near-IR imagers are revolutionizing our view of disk evolution and planet formation. Resolved disk observations show intriguing features, such as spiral arms, rings, narrow gaps, and asymmetries. These features are often interpreted as evidence for planet formation processes. However, resolved studies have so far been very biased toward the brightest systems and/or transition objects (protoplanetary disks with inner holes and gaps), which are clearly not representative of the entire disk population. Since current statistics on extrasolar planets imply that most circumstellar disks should be forming planets (big or small), it is important to investigate the full distribution of disk properties present in star-forming regions. In this talk, I will discuss demographic studies in nearby molecular clouds and the constraints they impose to both disk evolution and planet formation theory.

During the master thesis research, the broadband light curves of the flat spectrum radio quasar (FSRQ) 3C 273  obtained between September 2008 and August 2012, were analysed. The light curves covered a wide range of frequencies from radio to gamma-ray emission. We used the discrete correlation function (DCF) to search  for correlation between light curves at different frequencies. We found a correlation between the gamma-ray emission and the radio mm-emission, as well as with the optical polarisation, indicating thus a non-thermal origin for the gamma-ray emission. From the time lags we calculated from the correlation results, we obtained the relative separation distance between the gamma-ray and the radio emission regions. We observed two components for the X-ray emission, coming from two different regions in the jet.
For the PhD thesis, a high resolution 3-mm line survey performed by Plateau de Bure interferometre targeted two galaxies M 82 and IC 342, observing the innermost 100 pc of the centre of those galaxies. The aim is to get a complete inventory of the lines found in these galaxies, and try to identify the different chemical regions. PCA method is to be applied to the data for a better understanding of the kinematics of the lines. Moreover, VLA Data of IC 342 are being analysed to confirm the possible NH3 maser emission previously observed in the galaxy.

The nova legacy project started ~four years ago monitoring bright classical novae from outburst to 
years after outburst through UV+optical high resolution spectroscopy. In this talk I will present the
project and will show how the collected data allowed constraining the ejecta kinematic and physical 
properties and how these match the scenario of ejecta produced during a single event and in 
free/ballistic expansion.

Active Galactic Nuclei (AGN) are powered by accretion onto supermassive black holes and, besides being among the most luminous sources of radiation in the Universe, are also widely believed to play an important role in the evolution of their host galaxies. The parsec-scale material surrounding the accreting supermassive black hole is responsible for feeding the AGN, and connects the system with its host galaxy, providing important information on the feedback that nuclear activity produces on the galaxy.

In my talk I will summarize our current understanding of the close environment of accreting supermassive black holes obtained by X-ray and infrared studies of AGN, and present the results of our analysis of local Luminous and Ultra-luminous IR galaxies in different merger stages carried out in the hard X-ray band. I will discuss the relation between obscuration and merger stage, and compare our results with ALMA observations of these systems.

Direct imaging offers a unique way to detect and study exoplanets, very complementary to indirect techniques. I will present a brief review of high contrast imaging and highlight a few results obtained with SPHERE on the VLT. I will finally briefly give a personal view of the future of exoplanet imaging.

TBD

Nowadays there is growing observational evidence that type 1 and type 2 AGN are actually characterised by intrinsically different physical properties. In the past years, in the framework of the verification of the AGN unified model, there have been several attempts to detect faint broad emission lines in type 2 AGN with both NIR and polarised spectroscopy. We here present the results from a systematic study performed using deep NIR (VLT and LBT) spectroscopy of a sample of ~40 type 2 AGN, drawn from the complete SWIFT/BAT 70-month hard (14-195 keV) X-ray selected sample. Thanks to our new virial relation based on unbiased physical quantities, i.e. hard X-ray luminosity and Paβ emission line FWHM, we have been able to measure for the first time in a virial way the supermassive black hole mass (BH) of type 2 AGN, whose values have been up today estimated using indirect proxies (e.g. from scaling relations). With direct virial masses for type 2 AGN, we discuss, for the first time, if the BH-host galaxy scaling relations hold for our type 2 AGN, thus putting a missing piece to the AGN/galaxy co-evolution puzzle.

VLTI community days were recently held in Garching to discuss the current state of VLTI as well as plan for the future instrumentation and facility upgrade. This presentation will include a summary of the outcome of these community days as well as presentation of the VLTI Roadmap for the next 15 years that was recently proposed at the SPC meeting.

The cold phase of the interstellar medium has a central role in galaxy growth and evolution. In normal galaxies following the so-called “main sequence” of star-forming galaxies, the star formation rate is believed to be regulated uniquely by the amount of gas available, and more specifically by the mass of cold and dense molecular gas. Despite the enormous efforts to trace molecular gas in larger and larger samples of galaxies, at multiple scales and at multiple epochs, nearly all of our empirical knowledge of scaling relations linking molecular gas and galaxy properties is still based on observations of massive (e.g. M*>10^10 M_Sun), metal-rich and gas-rich spirals. There is therefore a strong motivation to test molecular gas scaling relations over a much broader dynamic range of galaxy properties. With this goal in mind, we have undertaken the “APEX low-redshift legacy survey of molecular gas (ALLSMOG)”, a survey of CO(2-1) line emission in a sample of ~100 normal star forming galaxies in the local Universe, characterised by stellar masses (10^8.5<M*[M_Sun]<10^10), SFRs and gas-phase metallicities significantly lower than have been probed by previous CO observations. The survey was completed in early 2016 and the final data products will be released soon (Cicone et al. submitted). I will present our latest results based on the full ALLSMOG dataset.

The large field of the MUSE 3D spectrograph allows us to start making extragalactic surveys mapping the Universe over that area in 3D. In my talk I will present data from the MUSE WIDE survey, which maps out "shallow" 1h observations over fields with deep HST data and excellent multiwavelength coverage, such as the Chandra Deep Field South/GOODS-S and the CANDELS-DEEP/COSMOS region. This "spectroscopy of everything" allows for a tremendous potential of interesting sources, that would not have been targeted in typical magnitude limited MOS spectroscopy. The main focus of my talk will be on the detection of 1608 emission line sources in the first 44 arcmin2 of this survey in the CDFS. Even with just 1 hour exposure times - at high redshift, MUSE finds >~10 Lyman Alpha Emitters / arcmin2, about 20% of those without a catalogued HST counterpart. I will present the resulting luminosity functions and present some cases of extreme equivalent width Lyman Alpha Emitters and also spectacular extended Lyman Alpha emission around these objects.

I will review the main results obtained in the laboratory on the chemical and physical modifications of rocky materials and ices exposed to ion bombardment. In particular I will discuss the effects induced on the spectral properties (reddening and darkening) of the irradiated samples mimicking asteroidal and TNOs surfaces irradiated by cosmic ions.

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Reflectance spectroscopy is currently the best tool we have to study the surface compositions of Trans-Neptunian Objects (TNOs), some of the most pristine objects in the Solar System. Understanding the surface compositions of these distant, icy planetesimals can reveal much about the Solar System’s formation and subsequent evolution. Despite more than two decades of study only water ice has been confirmed on the surfaces of small TNOs and so far their bifurcated colour distribution has gone unexplained. I will be presenting a short overview of these topics along with 7 TNO reflectance spectra observed with the X-Shooter spectrograph. 5 of these spectra are typical of TNOs while two exhibit unusual behaviour in the Near-UV that has never been seen before. Comparison with laboratory spectra of PAHs show that the absorption edge we observe appears to be most consistent with the presence of aromatic C-H bearing molecules on the surfaces of these TNOs.

I'll give an update on some spacecraft missions, including some results from Rosetta and plans for future missions that will continue the exploration of small bodies of our Solar System. This will include the proposed AIDA asteroid deflection experiment and proposed future science missions to the asteroid belt, Castalia and CASTAway. I'll include the links each of these have with telescopic observations, and pose a question for astronomers to consider over lunch: What would you do with a telescope located in the asteroid belt?

The detection extra-solar planets through radial-velocity searches is likely limited by the intrinsic magnetic activity of the host stars. The correlated « magnetic noise » that arises from their natural radial-velocity variability (jitter) can easily mimic and hide the orbital signals of super-Earth and Earth-mass exoplanets.
The modeling of the RV jitter is thus essential to extrasolar planets searches. I will present here a technique we can use to filter out the RV activity jitter of low-mass star as well as what we currently know about the magnetic field of cool stars.

Lyman alpha (Lya) emitters (LAEs) provide our best opportunity to study low-mass galaxies experiencing active phases of star formation. Lya photons are scattered by HI atoms and therefore LAEs could be used as tracer of the HI distribution and kinematics. Insights in the propagation and escape of Lya photons can be obtained studying local star-bursts. However, LAEs have been detected at any redshift and their properties are not homogeneous.
We selected a sample of 2 < z < 4 LAEs from the VUDS (VIMOS Ultra Deep Survey) survey and I will present how scattering and HI kinematics, such as star-formation outflows, can affect the escape and large-scale propagation of Lya photons. This can have implications for the LAE evolution and also for the understanding of the galaxy properties at the epoch of re-ionization.

Pre-main sequence stars are supposed to be very close to their birthplaces and to have velocities still very similar to the initial ones. In this context, the kinematic studies of young stars are fundamental to discuss their formation mechanism. In addition, individual distances to these objects have to be accurately determined to derive reliable ages and masses. Significant progress has been made in recent years using a variant of the trigonometric parallax method based on multi-epoch VLBI observations to deliver very precise and accurate parallaxes for a few remarkable stars in nearby clusters. Another method based on proper motions, radial velocities and the convergent point of a co-moving group of stars also exists and allows for the determination of individual parallaxes for all cluster members. In this talk I will present recent results on the distance determination of young stars in nearby star-forming regions and stellar associations using these methods. The newly derived distances are used in this work to investigate the cluster kinematics, structure and evolution but also to refine the physical properties of young stars (mass, age and the lifetime of circumstellar disks).

Through targeted investments in outreach, ESO has, by some measures, become the most visible ground-based observatory and among the best known observatories in general (ground and space). ESO’s education and outreach efforts are a reference point and inspiration for other outreach teams around the world, as well as a rich source of high quality content.

The new ESO Supernova Planetarium & Visitor Centre brings new opportunities to strengthen ESO's power brand. It also brings an opportunity for ESO staff to engage directly with the general public. In this talk, I will present the plans we have for the centre, how you can get involved, as well as an overview of the profound changes it has triggered for outreach. Hopefully an interesting discussion about ESO's outreach can be initiated, so please bring any questions that you always wanted to ask.

In the fourth session of the JAO series on Practical Interferometry, we discuss calibrators.  This follows the March presentation on data calibration.  Topics covered will include:

• Planetary models
• Quasar properties
• Flux accuracy
• Calibrator surveys
• Use of ALMA database

Rotational lightcurves are among the most powerful tools to study the physical characteristics of small bodies in the Solar system. The periodic short-term brightness variations of minor planets can be used to reveal their spin rates as well as to constrain their shapes, densities and compositions.
Despite the compelling opportunities this method provides, the number of Jupiter family comets (JFCs) and Trans-Neptunian objects (TNOs) with well sampled lightcurves remains too low for significant statistical analysis. The main reason for this lies in the observational challenges this technique poses. Mainly, lightcurves of minor planets require long observing times on large telescopes. Additionally, lightcurves require precise photometric calibration in order to detect the object’s subtle brightness variation across nights and observing runs.
We have developed a method for absolute photometric calibration of multi-epoch observations using the Pan-STARRS Data Release 1, which allows us to achieve low photometric uncertainties and to combine data sets taken at different instruments during different observing runs. Here, I will present the absolute calibration technique and the results from the analysis of our TNOs and JFCs lightcurve programs.

Ram pressure due to the intra cluster medium is a mechanism which can effectively remove interstellar gas from galaxies, particularly in the form of diffuse atomic hydrogen, HI. In this talk, I will first present the high-resolution HI imaging data of carefully selected Virgo galaxies from the VIVA survey (VLA Imaging of Virgo galaxies in Atomic gas) to overview how HI morphology and kinematics can be used to diagnose various stages of ram pressure stripping. Also, I will present the results from the phase-space analysis of the VIVA galaxies by stripping stage, to discuss to what extent the classical ram pressure stripping of radially infalling galaxies to the cluster potential holds. On the other hand, the cold star forming molecular gas is an essential element to be probed to understand the galaxy evolution during/after HI stripping. By presenting the SMA and the ALMA data of several VIVA galaxies, I will discuss how deeply the ICM pressure affects the ISM content of galaxies, including the dense molecular gas, and hence how the star formation activities may change.

The search for low mass exoplanets with radial velocities (RV) is hindered by stellar variability associated with magnetic activity, rotation and convection. Because the orbital timescales can be close to the stellar rotation period, a number of methods have been developed to separate the two signals.
I will present one such method which uses Gaussian processes as correlated noise models, in order to extract information about both the planets and stellar activity from RV observations. The method has been applied to CoRoT-7, a well-known planet-host star that shows activity-induced RV signals of the order of several m/s, and to other targets where activity is probably mimicking real planet signals. Valuable insights can be obtained from the study of these systems since future spectrographs like ESPRESSO, capable of reaching cm/s precision, will face these same challenges when trying to detect Earth-like planets.

I will present the project I am going to develop during my 3-month visit at ESO-Santiago. We want to investigate how Lyman alpha emission depends on environment and how/if Lyman alpha emitting galaxies trace/follow overdensity structures with certain gas and environment conditions. We make use of an home made code to define the environment and data from the VANDELS ESO-public survey to study the spectroscopic properties of Lyman alpha emitters

Evolved stars (subgiants and giants) are suited targets for precision radial velocity (RV) studies
by two main reasons: 1) they are cooler and rotate slower than their former main-sequence
progenitor, which allow us to achieve RV precision at the m/s level for intermediate-mass stars
, and 2) we can use them to study the dynamical evolution of planetary
orbits due to the interaction with the expanding stellar envelope.
Since 2009, we have been conducting a radial velocity survey called EXPRESS (EXoPlanets aRound
Evolved StarS) aimed at studying the population of planets orbiting giant stars.
So far, we have computed precision radial velocities for a sample of 166 bright giant stars, resulting in
the detection of more than 20 giant planets and brown dwarf candidates and 24 spectroscopic binaries.
In this talk I will describe our project and show the main results after more than 7 years of observations.

Nuclear activity and intense star formation are two phenomena known to co-exist in a variety of galaxies, spanning several orders of magnitude in luminosity. I will present a compilation of results derived from studies of type 1 and type 2 AGN, using Spitzer and Herschel data that aim at quantifying the effects of the two phenomena in the mid- and far-infrared. I will address the incidence of star formation in AGN and the effects of the AGN on the properties of their hosts, and I will discuss possible synergies between the Herschel data and present and future facilities.

The diffuse interstellar medium is an important component of the Galaxy, since it represent a significant fraction of the mass and volume of the neutral gas. Advanced numerical simulations are now producing realistic descriptions of the formation and destruction processes of molecular clouds in relation with the large scale Galactic structure. Among the key element which remain not well represented, the subtle interplay of the elemental physical and chemical processes which determine the gas composition and thermal state, with macroscopic perturbations such as spiral arm density waves or large scale shocks.  Such theoretical advances need to be cross checked by new set of observations, providing an extensive diagnostics of the physical and chemical state of the matter. Recent absorption surveys have been obtained thanks to the Herschel mission, leading to new diagnostics of the molecular hydrogen content and the cosmic ray ionization rate, and measurements of the carbon abundance and gas thermal pressure throughout the Galaxy. The spectacular jump in sensitivity achieved with ALMA (and NOEMA in the northern hemisphere) allows systematic absorption surveys of radio-loud QSOs. The comparison of various species allows to determine accurate molecular abundances in the diffuse gas. I will discuss in particular how the combination of Herschel and ALMA data allows to support the use of HCO+ absorption as a diagnostic of molecular hydrogen, even in CO-dark gas. A serendipitous detection with ALMA of HCO+ and HCN in the Galactic bulge indicates the presence of diffuse molecular gas within about 1kpc of the center of the Galaxy in agreement with existing determinations of extinction towards bulge stars. The absence of CO emission and the large fraction of hydrogen in molecular form can be understood as resulting from the relatively low FUV radiation field and high shear in the bulge.

Ultra-Compact Dwarf Galaxies (UCDs) have filled the void between classical globular cluster and dwarf galaxies in the scaling relations of early type systems.  The nature of these objects is still under debate. They are either the surviving nuclei of tidally stripped dwarf galaxies or the high mass end of the globular cluster mass function. Several studies show that the dynamical mass of UCDs is elevated compared to what is expected from their stellar population. One explanation for these elevated M/L ratios is the presence of a super massive central black hole (SMBH) that is expected if they are stripped nuclei.
Recently, a SMBH was detected in the Virgo cluster UCD M60-UCD1 (Seth et al. 2014). This SMBH makes up 15% of the mass of the UCD. This discovery is the clearest indication yet that UCDs originate from more massive progenitors. The elevated dynamical M/L ratios of massive UCDs suggests that more UCDs host SMBHs. Thus UCDs could contribute significantly to the overall census of black holes in galaxies.
I will present the results from a follow-up effort to resolve the kinematical signatures of the very centers of several UCDs in Centaurus A and the Virgo Cluster. We use adaptive optics supported spectroscopy with SINFONI to probe them for the presence of a SMBH in their centers. We created a grid of Jeans Anisotropic Models (JAM) to find the best fit dynamical model to our data and the best-fit black hole masses. This allows us to make a first tentative estimate of the SMBH occupation fraction in UCDs.

Globular clusters have played an important role in the study of the processes that led to the formation of our Galaxy. Moreover, the dual Galactic globular cluster system is considered a manifestation of its hierarchical formation in the context of the Lambda-CDM scenario. Wide-field imaging and spectroscopy are crucial tools to unveil the remnants of their progenitor dwarf galaxies, already assimilated by the Milky Way. In this talk, I will present our detections of the Sagittarius tidal stream around the globular clusters Whiting1 and NGC7492. Our results confirm that both clusters are inmersed in the stream but only Whiting1 was formed in the interior of the Sagittarius dwarf spheroidal and later accreted. More importantly, I will present new detections of the Sagittarius tidal stream in the southern hemisphere, which might help to better understand the orbit of this remarkable halo substructure.

In 2011 the Nobel Prize in Physics was awarded "for the discovery of the accelerating expansion of the Universe through observations of distant supernovae". These Type Ia supernovae (SNe Ia) are also the dominant contributor to iron-group nucleosynthesis and leading candidates for the elusive sites of high energy cosmic rays, the p-process isotopes, and the positrons responsible for the 511 keV annihilation signal in our Galaxy. SNe Ia are thought to be thermonuclear explosions of white dwarf stars. Despite their ubiquitous importance to cosmology and astronomy, their progenitor systems and the explosion mechanism(s) are still largely unknown. This "SN Ia progenitor and explosion mechanism problem" is one of the great unsolved problems in astrophysics, complicated by the fact that in recent years several unique sub-classes of SNe Ia have been described. I will discuss leading explosion models for SNe Ia, present results from multi-dimensional hydrodynamical simulations of the final seconds of the star's life, and highlight our quest to predict testable observables for the different suggested progenitor and explosion mechanisms of SNe Ia.

NaCo-ISPY is a deep L'-band coronographic angular differential imaging survey for wide-separation giant planets around nearby young stars with circumstellar disks. Our main goal is the revelation and characterization of the hypothesized, but observationally only partially characterized wide separation (>5-10 au) giant planet (GP) population during the time of formation (protoplanetary disks) and dynamical evolution (debris disks).
The ISPY survey is distinguished from other exoplanetary surveys, in that it exploits the L-band advantages and focuses on a very specific and coherent target group.
I will give an overview of the project, presenting the team members, the science goals, illustrating the target selection and prioritisation, as well as showing some preliminary results.

Periodic variability due to rotation and patchy cloud cover has been detected in L and T brown dwarfs, with higher variability amplitudes observed at the L/T transition. Directly imaged planets occupy the same temperature regime as L and T type brown dwarfs and are predicted to exhibit similar variability.  We are currently conducting the first survey of weather patterns on free-floating young planetary mass objects and young low mass brown dwarfs with NTT SofI. We aim to discover and characterise variability in these objects and to constrain the fraction that show periodic variability due to rotationally modulated patchy cloud cover. A comparison of our survey with surveys of field brown dwarfs will provide insight into the effects of surface gravity on cloud structure. Here I will present some preliminary results from this survey.

Molecular compositions of multiple species can be a great diagnostic tool to study stages of star formation or the external environment that surrounds molecular clouds. With ALMA, the potential of astrochemical studies in external galaxies has been greatly widened. In this talk, I will show two examples of such studies, M83 and NGC 3256.

M83 is a nearby face-on barred spiral galaxy. We observed the circumnuclear ring (the central few 100s of pc) with ALMA. Our observations show that there is an evolution in chemical compositions as the gas flow from the galactic bar into the circumnuclear ring to the downstream of the ring, likely inducing star formation along the way.

NGC 3256 is a starburst merger with powerful molecular outflows from both nuclei. In our observations, the variation of chemistry is seen among the two nuclei, tidal tails, and outflows. For example, shock tracers are enhanced in tidal tails or outflows. Although complex chemistry is not seen in outflows as expected from their hot and tenuous nature, dense gas tracers such as HCN and HCO+ are observed. The chemical features of two nuclei are similar to that of a local starburst such as NGC 253, and significantly lack complex molecules compared with another merger Arp 220. This difference with Arp 220 may be a reflection of a less compact nature of star formation in NGC 3256.

In the third session of the JAO series on Practical Interferometry, we discuss basics of data calibration.  Topics covered will include:

• Phase calibration
• bandpass calibration
• amplitude calibration
• WVR and Tsys Flagging
• Self-cal

We aim to bring together astronomers who are pursuing a variety of strategies to contribute in answering the question: “What constitutes a prototypical low-mass star forming region from core to cluster scales?” This question refers specifically to the formation of low-mass stars, but it also can incorporate, for example, higher-mass stars that form in environments shared with low-mass stars, parallels between low- and high-mass star formation, starless cores, brown dwarfs, planetary formation simultaneous with low-mass star formation, and related topics. We suggest that all contributions present observations (from any wavelength) and/or numerical simulation to provide a perspective that is crucial for a comprehensive understanding of low-mass star forming regions.

More information at http://www.eso.org/sci/meetings/2017/star-formation2017.html

I will present an overview of ASPECS: the ALMA Spectroscopic Survey in the Hubble Ultra Deep Field (UDF). The goal of this survey is to obtain a ultra-deep, unbiased census of the molecular gas and dust continuum emission in high redshift galaxies (z = 0−8). Our pilot survey covers a 1 arcmin^2 region of the Hubble UDF, and provides full redshift coverage for CO and [CII] line emission by performing frequency scans of the ALMA bands 3 and 6. Our observations are amongst the deepest ever performed in such a contiguous area, reaching down to ~13 micro-Jy in the 1.2-mm continuum maps. In this talk, I will highlight the main results from our pilot cycle-2 survey, preliminary findings from our cycle-3 ultra deep 1-mm data, and and I will show expectations from our recently approved ALMA large program.

Globular clusters are no longer a proxy for a single stellar population. High-precision photometric and spectroscopic observations have been revealing multiple generations in Milky Way and extragalactic old and young massive clusters. The connection with global parameters (mass, age, environment, chemical and dynamical evolution history of the host galaxy) is not clear. On one side, observers are carrying out surveys to collect more information in the Milky Way and Local Group galaxies, e.g. VVV, Gaia-ESO, APOGEE, GOTHAM etc. And on the other side, theoreticians are trying to make sense of all pieces of observations. Both sides together are trying to solve the puzzle of how star clusters form and evolve, and its connection with the host galaxy.

Among some questions we would like to address during these two days are:
Are massive young clusters the prototypes of future globular clusters? What is missing in stellar evolution models, in particular of evolved stars such as those in AGB and HB phase? What is the relation between stars in clusters and dwarf galaxies, and stars in the Galactic halo and bulge? What is the fraction of Galactic clusters formed in situ and those formed in dwarf galaxies captured by the Milky Way? What are the differences and similarities between star clusters in the Milky Way and Local Group galaxies? How can star clusters be used as tracers of the chemical and dynamical evolution history of their host galaxy? What is the best instrumental complement that is needed to answer these questions?

Optical imaging with microarcsecond resolution will reveal details on and around stellar surfaces but requires kilometer-scale interferometers.  Intensity interferometry, electronically connecting independent telescopes, has an error budget that relates to electronic time resolutions of nanoseconds and light-travel distances of centimeters or meters (rather than scales of an optical wavelength), circumventing issues of atmospheric turbulence.  Once pioneered by Hanbury Brown and Twiss, digital versions of this quantum-optical technique have now been demonstrated in the laboratory, reconstructing diffraction-limited images from measurements over hundreds of optical baselines.  Baselines up to a few km will soon become available with the Cherenkov Telescope Array (primarily built for gamma-ray studies), thus realizing an optical interferometer in software, somewhat analogous to that of ALMA at radio wavelengths.

The Reionization of the Universe is one of the most important and
hottest topics of the present day astrophysical research. The most
plausible candidates for the reionization process are star-forming
galaxies, which according to the predictions of the majority of the
theoretical and semi-analytical models should dominate the HI ionizing
background at z>3. We have used deep U-band imaging in the COSMOS,
CANDELS GOODS-NORTH, and EGS fields in order to estimate the Lyman
continuum escape fraction of 69 star forming galaxies at z~3 down to
faint magnitude limits (L=0.2L*). We have measured a stringent upper
limit (<2%) for the escape fraction of HI ionizing photons from bright
galaxies (L>L*), while for the faint population (L=0.2L*) the limit to
the escape fraction is <10%. We have computed their contribution to
the observed UV background at z~3 and we have found that it is
difficult to keep the Universe ionized at z~3 only with star-forming
galaxies. We compare our results with recent achievements on the Lyman
continuum escape fraction of high-z galaxies and AGN in the
literature and discuss future prospects to shed light on the Dark Ages.

In the second session of the JAO series on Practical Interferometry, we discuss receivers and correlators.  Topics covered will include:

• mixers,
• amplifiers
• wavefront tracking
• cross correlation to produce visibilities
• spectral performance
• Tsys and Trx
• Receivers, IF

The first billion years after the Big Bang represent the final observational frontier

The "Practical Interferometry" series at JAO will take place periodically in 2017 during our normal colloquium time slot.  The goal is to have a general understanding of mm-wave interferometry, applicable to ALMA.  Presentations will be given by JAO members on various topics of expertise.  The target audience will be ESO/ JAO fellows and postdocs, and while this will guide the level of the presentations, all who are interested are invited to attend.

In the first of this series, we will present basic concepts of (mm) interferometry:

• Definitions and principles
• Explanation of single dish vs. interferometry observations
• Van-Cittert Zernike's theorem

Damped Lyman-alpha absorbers (DLAs) provide a powerful and precise method for studying the metallicity evolution at high redshift, and reveal detailed information about kinematics of the absorbing gas. However, for many years the physical nature of the galaxies in which the absorption arises has been mostly unknown, especially in terms of fundamental properties such as their sizes, masses, and star formation rates. Recently, the situation at high redshift has changed thanks to near-IR spectrographs (X-shooter and SINFONI in particular). In this talk I will present recent results from our survey targeting high-metallicity DLAs with X-shooter in order to search for emission counterparts of the absorption.

We find a high detection rate (7/11) in our high-metallicity sample, significantly higher than studies of blindly selected DLAs. Comparing the results, as well as previous literature studies, to a model in which DLA absorption arises from low-luminosity star-forming galaxies, we demonstrate that DLAs follow a relation between metallicity and luminosity. Moreover, we highlight the future prospectives of using DLAs as probes of the low-luminosity end of the luminosity function in the distant Universe.

Intermediate-age star clusters in the Large Magellanic Cloud show extended main sequence turn offs (MSTOs), which are not consistent with a canonical single stellar population. These broad turn offs have been interpreted as evidence for extended star formation and/or stellar rotation. Since most of these studies use single frames per filter to do the photometry, the presence of variable stars near the MSTO in these clusters has remained unnoticed and their impact totally ignored. We model the influence of Delta Scuti using synthetic CMDs, adding variable stars following different levels of incidence and amplitude distributions. We show that Delta Scuti observed at a single phase will produce a broadening of the MSTO without affecting other areas of a CMD like the upper MS or the red clump; furthermore, the amount of spread introduced correlates with cluster age as observed. This broadening is constrained to ages ~1-3 Gyr when the MSTO area crosses the instability strip, which is also consistent with observations. Variable stars cannot explain bifurcated MSTOs or the extended MSTOs seen in some young clusters, but they can make an important contribution to the extended MSTOs in intermediate-age clusters.

Planetary transits have proven to be one of the most efficient means of finding planets outside the Solar system, counting over 2500 exoplanet discoveries. These transiting planets are paramount for the study of exoplanet atmospheres as the stellar light is filtered through the planetary atmosphere during transit and planetary absorption signatures become imprinted on the stellar spectrum. Observations of hot-Jupiter transmission spectra have become increasingly numerous and reliable throughout recent years, allowing detailed constrains on the planet's physical and chemical atmospheric properties, interactions between planet and host star, and planet formation history. While early work relied largely on space-based facilities, ground-based techniques have seen major advances recently and have become instrumental in performing an extensive and comparative study of exoplanet atmospheres. I will review the current state of knowledge, summarize recent results and discuss future prospects of exoplanet characterization, with a focus on the potential of ground-based facilities. In particular, I will present recent and new results by our team on the transmission spectra of several hot Jupiters.

The Planck space mission, as well as balloon and ground based experiments
in Atacama and Antarctica, are measuring the sky polarization at sub-mm and
mm wavelengths with unprecedented sensitivity. The data analysis involves
research in cosmology and Galactic astrophysics, which might lead to a major
discovery for fundamental physics. The main goal  is to
characterize anisotropies in polarization of the Cosmic Microwave
Background (CMB) with sufficient precision
and confidence to detect the expected signature from primordial
gravitational waves. At the same time, we are getting the data needed to
characterize interstellar magnetic fields and their
coupling with matter and turbulence in the diffuse
interstellar medium and molecular clouds.  I will introduce these two
research fields that have become interconnected, present current
results and future perspectives.

Calibration is a critical component in the conversion of  raw data to material  ready for  scientific  analysis.   Consequently a complete, consistent  calibration plan  for  each data  set fulfilling  quality control criteria was recognized as a cornerstone of VLT operation.  In 2007, ESO organized  its first calibration workshop to  (a) foster the sharing of  information, experience and techniques  between observers, instrument developers  and instrument operation teams,  (b) review the actual precision and limitations of the applied instrument calibration plans, and (c) collect the current  and future requirements by the ESO users. It focused on calibration issues affecting the first generation instruments.

More information at http://www.eso.org/sci/meetings/2017/calibration2017.html

After presenting the importance of the neutral to molecular transition in galaxies and discussing
the physical processes that govern the conversion, I will show how quasar absorption line
spectroscopy allows one to study the neutral and molecular phases of the ISM at high redshift.

NGC 1277, a lenticular galaxy in the Perseus Cluster, has been proposed to host an unusually massive central black hole (BH) of 1.7 x 10^10 Msun, based on stellar-kinematic data. With such a large BH mass, NGC 1277 would be a significant outlier from the empirical correlations between supermassive BHs and their host spheroids. More recent stellar-kinematic measurements indicate a lower BH mass, closer to 5 x 10^9 Msun, so that the implications for the BH-galaxy correlations have been re-assessed. I will present our alternative, gas-kinematic analysis of the BH mass in NGC 1277, which is based on CO(1-0) data obtained with the IRAM NOEMA Interferometer. I will also discuss our results on star formation and nuclear activity in NGC 1277 in view of the previous suggestion that NGC 1277 might be a relic galaxy providing a window into the z~2 Universe.

The motivation to study anomalous sightlines of highly reddened Galactic stars comes from Type
Ia Supernovae observations, which show peculiar extinction laws with very low RV values, as well 
as peculiar polarization wavelength dependencies with peak polarization at very low wavelengths 
(lmax<0.4 mm). Thus, the aim of this work is to spectro-polarimetrically investigate Galactic stars 
with low RV values in order to possibly find similarities to the polarization wavelength dependencies 
observed in SNe Ia sightlines.
We observed a subsample of highly reddened Galactic stars with anomalous extinction sightlines, 
extracted by Mazzei & Barbaro (2011), with VLT/FORS2, CAFOS (Calar Alto) and AFOSC (Asiago 
Obsevatory), and find that, despite low RV values, they have normal polarization dependencies.

In this talk, I will review the historical and human steps that lead to the discovery
of quasars and how one can derive some of their fundamental properties
in a simple way. I will then present example of science topics that can
be addressed using quasar absorption line spectroscopy.