NGC 1097 is a nearby Seyfert 1 galaxy with a bright circumnuclear
starburst ring, a strong large-scale bar and an active nucleus. One of the
goals of KINGFISH Herschel Open Time program is to study general trends of
the ISM heating and cooling in nearby galaxies. I present a detailed study
of the spatial variation of the far infrared (FIR) [CII]158um and [OI]63um
lines and mid-infrared H2 emission lines as tracers of gas cooling, and of
the polycyclic aromatic hydrocarbon (PAH) bands as tracers of the
photoelectric heating. The photoelectric gas heating efficiency
([CII]158um+[OI]63um)/PAH in the ring is estimated as ~ 50% lower than in
the spiral arms. The average 11.3/7.7um PAH ratio is also lower in the
ring, which may suggest a larger fraction of ionized PAHs, but no clear
correlation with [CII]158um/PAH(5.5-14um) is found. PAHs in the ring are
responsible for a factor of two more [CII]158um and [OI]um emission per
unit mass than PAHs in the Enuc S, which can be an alternative explanation
for the differences in gas heating efficiency. Much of the the H2 emission
in the starburst ring could come from warm regions in the diffuse ISM that
are heated by turbulent dissipation or shocks. I also present results for
other galaxies in the KINGFISH sample, focusing on starburst rings and
other resolved regions of enhanced star-formation.

29 articles ont été soumis et rendus publics fin mars sous l'appellation commune
"Planck 2013 Results:...". Ils constituent la première publication des résultats
cosmologiques de Planck, s'appuyant sur les 15 premiers mois de données et l'état
actuel de leur traitement. Simultanément, les données traitées et calibrées sont
rendues publiques. Les résultats concernant la polarisation seront disponibles
ultérieurement. Ces articles décrivent les données, leur traitement et leur
interprétation. La mesure du fond cosmique micro-ondes montre un accord
avec le modèle LambdaCDM avec une précision sans précédent. D'autres résultats
remarquables illustrent l'intérêt de Planck pour les astrophysiciens. Je
m'efforcerai de donner à la fois un aperçu des résultats principaux et un point
de vue personnel sur le déroulement de ce projet hors normes à plus d'un titre.

The magnetic fields of planets and rapidly rotating stars are maintained by
convection-driven dynamos operating in their interiors. Scaling laws derived
from geodynamo-like models successfully predict the magnetic field strength of
a wide range of astrophysical objects from Earth and Jupiter to some
rapidly-rotating stars. This emphasises the similarities between the dynamo
mechanisms at work in planets and active M dwarfs.

Recent spectropolarimetric observations of M stars show a broad variety of
large-scale magnetic fields encompassing dipole-dominated and multipolar
geometries. Combining global-scale numerical dynamo models and observational
results, we want to better understand the similarities of dynamos in planets
and low-mass stars. To study the physical mechanisms that control the magnetic
field morphology in these objects, we have explored the influence of rotation
rate, convective vigor and density stratification on magnetic field properties
in anelastic dynamo models.

In such models, the relative importance of inertia in the force balance -
quantified by the local Rossby number - is thought to have a strong impact on
the magnetic field geometry. The observed transition between dipole-dominated
and multipolar large-scale dynamos in early to mid M dwarfs is therefore
tentatively attributed to a Rossby number threshold. We interpret late M
dwarfs magnetism to be the consequence of a dynamo bistability occurring at
low Rossby number, and predict different amplitudes of differential rotation
on these two dynamo branches. Th

The Horsehead mane is a particularly interesting case for the study of photodissociation regions because the transition from the diffuse, hot and ionised gas to the dense, cold and shielded gas is sharp. The PDR geometry is simple (viewed edge-on) and the density profile across the PDR is well constrained. The combination of small distance to Earth (at 400 pc, 1" corresponds to 0.002 pc), low illumination (χ= 60) and high density (nH ~ 105 cm-3) implies that all the interesting physical and chemical processes can be probed in a field-of-view of less than 50" (with typical spatial scales ranging between 1 and 10"). The rsehead PDR is a good source to benchmark the physics and chemistry of UV illuminated neutral gas.
In this talk, I will summarize some results from the Horsehead WHISPER, a sensitive, high spectral resolution, full 1, 2 and 3mm spectral survey of 2 positions in the Horsehead Nebula obtained at the IRAM 30m telescope. This will include 1) H2CO, CH3CO photo-desorption 2) (iso)-nitriles in UV illuminated gas 2) the 2nd detection of CF+ (hyperfine structure and fluorine abundance) 3) the first detection of the new hydrocarbon cation C3H+.

IRIS is a new generic 3D radiative transfer code for the prediction of high-resolution synthetic spectra (Ibgui et al. 2013). IRIS solves the monochromatic 3D radiative transfer equation. This tool provides the capability of relating theoretical Magneto Hydrodynamics or Radiation Hydrodynamics (RMHD) models to the spectral emissions of the studied objects or structures for further comparisons with observations.

I will outline the key features of IRIS. In particular, the code can handle periodic media. It also takes into account the velocity gradient effect for arbitrary velocity fields. I will introduce its future extensions that will allow the treatment of scattering and non-LTE situations.
IRIS has post-processed a 3D RHD model of a radiative shock calculated by the 3D code HERACLES. I will discuss the hydrodynamic and radiative structure of the shock. I will comment on the results of a comparison of the radiation moments calculated by the grey M1 model of HERACLES and by the exact method of IRIS. Further, I will present theoretical spectra that emerge from radiative shocks, and discuss their angular and spectral distributions.

Dark matter (DM) is the dominant component of galaxies. Warm dark matter (WDM, DM particles of mass in the keV scale) is able to solve naturally the serious drawbacks of cold dark matter (CDM) at small and galactic scales, keeping all its successes at large and cosmological scales. Namely:
(i) WDM produces the correct abundance of substructures at redshift zero and higher redshifts.
(ii) Quantum mechanics turns to play a crucial role in small scale WDM galaxy structure (kpc scales and below).
(iii) Compact dwarf galaxies turn to be natural quantum macroscopic objects, supported against gravity by the fermionic WDM quantum pressure, while the large galaxies appear naturally in the dilute and classical regime.
(iv) The Thomas-Fermi semiclassical approach of atomic physics implemented here for fermionic WDM galaxies yields the main physical galaxy magnitudes: mass, core radius, phase-space density, velocity dispersion, fully consistent with observations for all types of galaxies from the compact dwarfs to the large galaxies, spirals, ellipticals . In particular, quantum fermionic WDM provides galaxy cores and their sizes in the right observed scales. The theory of galaxy structures, formation and evolution turns to be considerably clarified in WDM and placed in the framework of physics and cosmology. WDM galaxies are the analogous of stars as treated by Chandrasekhar, Landau, Bethe, ......

Dark matter (DM) haloes, the cradles where galaxies form and evolve, acquire angular momentum in a stochastic way which results in a final non-zero DM adimensional spin parameter. We will see how this process translates into the ability of the galaxy, living in this DM halo, to form stars. To do this we will first measure this stochasticity from the Millennium II simulation, and then see how it affects the properties of the disc of baryons that forms in the center of a DM halo. We will see that the smooth infall of matter comes in chunks with almost, but not quite, random angular momenta, which affects the ability of a disc to form stars and also the frequency of instabilities in the disc leading to the formation of bars and pseudo-bulges.

The spectral synthesis of 2 powerful distant (z=4) radio galaxies
are computed with the new code Pégase.3, predicting stellar, gaz, metal
masses and the coherent dust emission, covering the UV-IR-submm range
(Rocca-Volmerange et al. 2013).
Two young and old stellar components (starburst and elliptical galaxies)
are identified as well as a faint active nucleus. Masses and ages
provide strong constraints on the physics of galaxy evolution likely
driven by massive starbursts from the earliest epochs of the Universe.
Consequences on theories are discussed

Supernova Remnants (SNRs) play a vital part in the interstellar medium, where they re-distribute large amounts of energy, and probably constitute the primary sites for accelerating galactic cosmic rays. In my talk, I will present recent observations, mostly from the APEX, SOFIA (CO), and Spitzer (H2) telescopes, of various SNRs, all detected at TeV energies by the Fermi telescope. I will show that such observations are an efficient way to improve our knowledge of the physical and chemical conditions prevailing in SNR environments. I will also show how comparisons with shock models constitute a valuable tool to constrain both the shock characteristics and pre-shock conditions, leading to accurate estimates of shocked gas masses and related energetics. During this talk, I will focus on the F knot of the SNR W28, and present how our various IC443 observation programs will contribute to make this object a reliable template for the study of Galactic SNRs.

Convection is a key process in stellar interiors. It is characterized by large
Reynolds numbers, implying a highly turbulent regime. I will show how
multidimensional hydrodynamical simulations allow us to get a physical insight
of this complex phenonemon. The numerical results are obtained with a novel
hydrodynamical code, MUSIC, which is based on time-implicit methods. I will
present the general framework and discuss the advantages of implicit methods in
tackling stellar hydrodynamical problems.

La poussière est une composante majeure des galaxies. Son étude au travers d’expériences de laboratoire, associées aux observations, permet de déduire la composition et l’évolution des différents types de grains du cycle de la matière dans une galaxie.
Une partie importante de la poussière interstellaire est constituée de carbones amorphes hydrogénés (a-C:H ou HAC). Ces grains hydrocarbonés sont détectés par leurs signatures spectrales infrarouges, largement observées dans le milieu interstellaire diffus de la Voie Lactée ainsi que dans de nombreuses autres galaxies. Le fait qu’ils ne soient, par contre, pas détectés dans les nuages interstellaires denses pose la question de leur évolution induite par les processus d’altération astrophysiques.
Je présenterai mes travaux sur l’étude de ces grains interstellaires. Les récents résultats, obtenus à la fois au travers de nouvelles observations, ainsi que grâce à la synthèse et la caractérisation d’analogues de laboratoire, permettent notamment de mieux connaitre l’émission visible de ces poussières carbonées ainsi que leur évolution due aux rayons cosmiques.

Understanding the structure and evolution of disks surrounding young low-mass stars is one of the key issues to study the process of planet formation. Nevertheless the overall properties of those disks are not yet well constrained by observations. Observations of molecular lines is a useful tool to constrain the disks physical structure, as different molecules sample different physical conditions. Beside the abundant CO, several other molecules have been detected in the outer part of the disks in the millimeter domain (e.g. HCO+, H2CO, CS, HCN, CN...). In this talk I will present recent results obtained with both single dish and interferometer, and I will confront them to models of
protoplanetary disks, in particular to the layered structure that is predicted by all chemical model so far.

For approximately half a century, core-collapse supernovae have posed a vexing puzzle for theorists despite being a major ingredient (and uncertainty) in fields ranging from stellar and galaxy evolution to the interstellar medium. Historically, advances in core-collapse theory have been linked to advances in computing power and software. Supernovae are inherently multi-dimensional objects in which neutrino transport, gravity, hydrodynamic instabilities and convection play important roles. Three-dimensional simulations incorporating sufficient physical fidelity require extensive high-performance computing resources and codes efficient enough to use the associated architecture. In this talk, I will highlight recent advances in the field. In particular, I will discuss the dependence of spatial dimension on the viability of the delayed-neutrino mechanism and how pulsar kicks naturally arise from core collapse.

The eccentric orbits of the known extrasolar giant planets provide evidence that most planet-forming environments undergo violent dynamical instabilities. We numerically simulate the impact of giant planet instabilities on planetary systems as a whole. We find that populations of inner rocky and outer icy bodies are both shaped by the giant planet dynamics and are naturally correlated. The orbital distributions of outer planetesimal disks can be drastically altered by the giant planets; in the most extreme cases they can be converted into 100 AU-scale isotropic clouds (aka "mini Oort clouds"). Strong instabilities - with very eccentric surviving giant planets - completely clear out their inner and outer regions. In contrast, systems with stable or low-mass giant planets form terrestrial planets in their inner regions and outer icy bodies produce dust that is observable as debris disks at mid-infrared wavelengths. Fifteen to twenty percent of old stars are observed to have bright debris disks (at lambda ~ 70 microns) and we predict that these signpost dynamically calm environments that should contain terrestrial planets.

I will present a study on the formation of early-type galaxies (ETGs) through mergers with a sample of 70 high-resolution numerical simulations of binary mergers of disc galaxies and 16 simulations of ETG remergers. These simulations, designed to accompany observations and models conducted within the Atlas3D project, encompass various mass ratios, initial conditions and orbital parameters. I will show that binary mergers can produce both fast rotating and slow rotating galaxies. Most Slow Rotators formed in these binary disc mergers hold a stellar Kinematically Distinct Core (KDC) in their ~ 1-3 central kilo-parsec: these KDCs are built from the stellar components of the progenitors. Using the GalMer database of galaxy mergers, we can confirm the importance of the spin of the progenitors in the formation of the fast and slow rotating galaxies. With the implementation of stellar populations models, these simulations are also useful to constrain the formation and the growth of ETGs via dry galaxy mergers.

In this talk, I will mainly focus on our recent results for the near-infrared
molecular hydrogen emission in the central 3 x 3 arcsec of Perseus A (NGC 1275), which are based on data obtained with the Near-Infrared Integral Field Spectrograph (NIFS)
and the ALTAIR adaptive-optics system (Gemini North).
The data support a scenario in which shock-excited molecular hydrogen enters
into the circum-nuclear region of Perseus A in the form of one or more streamers
and settles into a turbulent, clumpy or unstable accretion disc in the inner
R ~ 50 pc. Our results include an estimate of the mass enclosed by the molecular
hydrogen disc, which will be discussed in view of the M-sigma relation and black
hole mass estimates from the literature. I will examine the relative importance
of jet feedback and accretion in driving shocks and turbulence in the
molecular-gas component of Perseus A. I will also review other modes of AGN
feedback, including examples from our ongoing optical IFU study of bright
type-1 Seyfert galaxies at z<0.06.

A massive black hole sits in the heart of the Milky Way. One
consequence of the black hole is that it ejects "hypervelocity stars" from
the Milky Way at ~1000 km/s velocities. We discovered the first
hypervelocity star in 2005, and since then our targeted survey has
discovered 20 unbound stars and a comparable number of possibly bound
hypervelocity stars. Recent results include new constraints on their
origin in the Milky Way, a surprising anisotropic spatial distribution
over the sky, and Hubble Space Telescope proper motion measurements that
may allow us constrain the shape and orientation of the Galactic
potential.

Spectroscopic surveys of quasars yield a random sample of
intervening absorbing gas clouds that can be used to constrain the
on-going and summative enrichment processes in the universe. The CIV
doublet has proven to be an important tracer of the IGM and its
evolution from z = 6 to 0. This transition has been well-studied at
high redshift because: it is a strong transition of a common metal; it
is observable outside the Ly-alpha forest, where it becomes easier to
identify; it redshifts into optical passbands for 1.5 < z < 4.5; and
it is a resonant doublet, which gives it distinctive characteristics
that enable surveys to be largely automated. We have vastly improved
the 1.5 < z < 4.5 absorber measurements by identifying over 15,000 CIV
systems from a survey of thousands of SDSS DR7 QSOs. No longer
dominated by Poisson errors, the CIV redshift (non)evolution stands
out clearly. For example, the shape of the CIV distribution has not
evolved over the 3 Gyr span of the sample, but there has been a
two-fold increase in the CIV number density (detected at > 30 sigma).
Since the strong CIV absorbers detectable in SDSS spectra likely arise
in the extended gaseous halos of galaxies, we can show that the change
in the number density is probably largely driven by the change in the
number of galaxies. We also constructed a uniform 0 < z < 6 dataset by
combining the SDSS survey with the z < 1 HST results (Cooksey et al.
2010) and the new z > 5 FIRE results (Simcoe et al. 2011). Thus, we
can compare apples-to-apples: the absorber density over time and the
CIV mass density evolution. This is the first in a series on our
surveys for various metal-line absorption systems in SDSS DR7 QSOs,
and we share some other unexpected discoveries.

AGN jets are more than capable of staving of catastrophic cooling of the intracluster medium (ICM) in the cores of cool-core clusters. However, preventing catastrophic cooling requires the ICM to be heated nearly isotropically. Narrow bipolar jets are extremely inefficient at heating the gas in the transverse direction. Recent detailed studies of individual cool-core clusters show that successive generations of jet-lobe-bubbles are offset, often significantly, in the angular direction on the sky. Since the spin and the jet axises are one and the same, we interpret this as evidence that the spin axis of the supermassive black hole (SMBH) at the centers of these clusters is prone to change directions on timescales shorter than the gas cooling time in the cores. We argue that due to the extant conditions in the cluster cores, the SMBHs experience short stochastic episodes of enhanced accretion via thin, typically misaligned, accretion disks that, in turn, cause the black holeu2019s spin axis to slew and change direction rapidly. Our model not only explains how AGN byproducts can end up tracing a nearly isotropic angular distribution about the cluster center but also explains how AGN jets effect isotropic heating. Since SMBHs that host thin accretions will manifest as quasars, our model predicts that to the extent that the characteristics of the cluster population (i.e. the fraction of strong cool-core clusters, etc.) are comparable to those in the local universe, we expect a quasar at the centres of 1-2 systems within z < 0.5.

After an overview of ALMA capabilities for the upcoming Phase-I deadline
of July 12, I will present a brief discussion of tools for the treatment of the
data available at the LERMA.

Les étoiles massives réagissent de multiples façons sur le milieu dans
lesquelles elles se sont formées, et notamment les nuages moléculaires.
Je me concentrerai aujourd'hui sur deux effets nouveaux: (i) au cours de
leur vie, leurs vents stellaires créent de vastes bulles de plasma chaud
visibles en rayons X diffus; à son tour, ce plasma réagit avec les
nuages moléculaires froids environnants, donnant naissance à des
réactions d'échange de charge à leur contact, vues sous forme de raies X
non-thermiques particulières; (ii) à la fin de leur vie, leur explosion
en supernova créent des ondes de choc, qui accélèrent des particules.
Celles-ci interagissent avec les nuages moléculaires, pour donner à
haute énergie des photons gamma (GeV-TeV), détectés par HESS et Fermi,
mais aussi à basse énergie, provoquant localement une forte
surionisation des nuages moléculaires, récemment détectée dans le
domaine submillimétrique, via les radicaux DCO+ et HCO+.

Galaxy evolution is fortunate to be a data-rich research field. But the constant stream of new results can bring with it some difficulties. When data are rare, there is at least time to become familiar with the competing theories before each new result is published. Conversely, when theories are regularly adapted in response to each new set of observations, it can be difficult to extract from literature the physical explanations that have, or have not, been ruled out. With this in mind, we review key issues arising from the latest high-redshift galaxy surveys, but focus on reexamining the observational samples in terms of the simple, physical limits from which our complex galaxy formation models are built:
- Could they even have formed according to standard cosmology, and natural cooling and infall thresholds?
- How would they continue to evolve under certain limiting cases of mass accretion?
- And what fraction of the familiar, low-redshift population might these
first glimpses of the early Universe really represent?

The tight links between supermassive black hole (SMBH) and galaxy spheroid mass observed in the local Universe strongly suggests they have grown concurrently. However, the large-scale mechanisms that drive SMBH and galaxy growth remain poorly understood, especially at high redshifts. While major-mergers between galaxies provide a natural route to intense star-formation and rapid SMBH growth, observations of the high redshift Universe have begun to question the importance of such dramatic events, instead suggesting that most stellar mass was put in place via slower, "secular" processes. In this talk, I will explore SMBH growth in terms of this secular vs. major-merger view of galaxy evolution in an attempt to determine how today's SMBHs acquired their mass.

La vie, est-elle arrivée sur Terre de l’espace ? Notre expérience spatiale représente un test (partial) de cette hypothèse [1]. Dans le cadre du projet EXPOSE de l’ESA nous avons exposé des graines d’Arabidopsis Thaliana (l’Arabette des Dames) et de Nicotiana tabacum (tabac)
à l’extérieure de l’ISS pendant 18 mois. Nous avons mesuré la capacité de ces graines de germer au retour sur Terre, graines ayant subis pendant 18 mois les effets du rayonnement solaire, rayons cosmiques, variations de température et vide spatial existant à 440 km d’altitude. Les effets de ces divers paramètres ont été évalués. Les résultats ont montré qu’une graine de plante, ou une entité biologique similaire, pourrait survivre un transfert directe de Mars à la Terre ayant lieu en une année, durée courte, mais statistiquement possible.

Ce travail, qui comporte également des expériences de simulation au laboratoire, a été effectué, en collaboration intense, par David Tepfer (D.R. INRA) et Andreja Zalar (Docteur de l’ Univ.Versailles), biologistes des plantes à l’INRA de Versailles, et avec l’aide de Norbert Champion (LERMA, Obs.Meudon) et Soeren Hoffmann (ASTRID Synchrotron, Aarhus, Danemark).

[1] D.Tepfer, S.Leach, « Plant Seeds as Model Vectors for the Transfer of Life Through Space », Astrophys.Space Sci. 306 (2006) 69.

In most domains of astrophysics, knowledge of the distances to the objects
being studied is crucial. This is the case for stars in our Galaxy, which
will be spectacularly addressed by the upcoming Gaia mission. Currently,
two satellites are observing the Milky Way's interstellar medium (ISM) :
Herschel and Planck. The views that we are getting of the dust and gas are
at higher resolution and sensitivity to anything previously available.
However, in the plane of our Galaxy, the emission comes from a large range
of distances and environments and is concentrated in a relatively thin strip.
Not only do we need distances to infer physical sizes, masses and other
parameters of sources being studied, but we need to separate the different
contributions to the observed signal if we hope to perform a robust analysis.
I will present work that I have undertaken to explore the third dimension in
Galaxy, using stellar observations as well as thermal dust emission and radio
emission from the ISM. I will also discuss the long awaited ESA mission Gaia,
and its implications for the study of the ISM.

Les grands relevés spectro-photométriques comme le VVDS permettent
de déterminer la distance de milliers de galaxies et d'apporter des
contraintes sur les modèles cosmologiques et l'évolution des propriétés
globales des galaxies (luminosité, masse, environnement, ...).
Mais les observations et notamment les spectres de ces galaxies
contiennent beaucoup plus d'informations permettant d'affiner plus
précisément les modèles d'évolution physique et chimique.
Je ferai le point sur quelques résultats récents et sur les perspectives
attendues avec les nouveaux instruments (MUSE, EMIR, Euclid, ...).

Within the hierarchical framework for galaxy formation, minor merging
and tidal interactions are expected to shape large galaxies to this
day. As part of a pilot survey, we have carried out ultra-deep,
wide-field imaging of some isolated spiral galaxies in the local
universe with data taken at small (0.1 to 0.5-meter diameter),
robotic telescopes that provide exquisite surface brightness
sensitivity. Our observational effort has led to the discovery of
previously undetected giant stellar structures in the halos of
these spiral galaxies, likely associated with debris from tidally
disrupted satellites. Our collection of galaxies presents an
assortment of tidal phenomena exhibiting strikingly diverse
morphological characteristics. Our preliminary comparison with
available stellar halo simulations set in a Lambda-Cold Dark Matter
cosmology suggests that this extraordinary variety of morphological
specimens detected in our survey could represent one of the first
comprehensive pieces of evidence to support that the hierarchical
formation scenarios predicted by these theoretical models apply
generally to galaxies similar to the Milky Way in the Local Volume.
Finally, I will also present the discovery of a tidal stream around
a nearby dwarf irregular galaxy with our small telescopes. Followup
observations with Subaru telescope show this stream completely
resolved into stars, providing observational evidence of a minuscule
merger in a LMC-type system in the local universe. This result
suggests that dwarf accretion could play an important role in the
star formation history and evolution of nearby dwarf galaxies.

The dark matter particle has not (yet?) been detected, and
its nature is still unknown. Lambda Cold Dark Matter (LambdaCDM) is
the currently favoured paradigm for structure formation in the
Universe: it is very successful in explaining the observations of
large scale structures in the Universe, but on galaxy scales there is
a discrepancy between observations and (dark matter only) LambdaCDM
predictions. I will introduce the dark matter problem in galaxies, I
will talk about advances that have been made in deriving the
distribution of dark matter in galaxies, and I will discuss future
projects that will enable us to shed more light on dark matter,
including the HALOGAS (Westerbork Hydrogen Accretion in LOcal
GAlaxieS) survey, the deepest HI survey of a sizeable sample of spiral
galaxies.

We discuss the effects of supermassive black hole (SMBH) outbursts on
the hot atmospheres of early type galaxies, galaxy groups, and galaxy
clusters whose atmospheres are only seen through X-ray
observations. The discussion is motivated by the need to understand
the separation of galaxies into their two fundamental classes - the red
and "dead" early type galaxies with little star formation and the
blue clound (spiral, actively star forming galaxies). We show the
detailed effects of the outbursts from the supermassive black hole in
M87 at the center of the Virgo cluster using Chandra and XMM-Newton
observations including buoyant bubbles of relativistic plasma produced
by the central SMBH, uplifted filaments of X-ray emitting gas, and the
Mach 1.2 shock. We present the results from a large survey of more
than 100 early type galaxies observed with Chandra. From the X-ray
images, we identify the sample of hot coronae that show gas cavities,
estimate cavity ages, and compute the mechanical power needed to
inflate the cavities. From the X-ray luminosities, we derive
Eddington ratios and briefly discuss the accretion mode for these
low-luminosity actice galactic nuclei. We compare the early-type
galaxy AGN to their more powerful counterparts in rich clusters.
Finally, we show the dramatic effects that SMBH outbursts can have on
galaxy-scale hot coronae.

The Plateau de Bure Arcsec Whirlpool Survey (PAWS, PI: E. Schinnerer) has imaged
the CO(1-0) emission in the central 8 kpc of the nearby spiral galaxy M51.
Our final data is a combination of the IRAM 30m single-dish and Plateau de Bure
interferometer observations, reaching a linear resolution about 45pc and with
sensitivity to giant molecular clouds (GMCs) above 10^5 Msun. Thanks to such
high quality data, we are able to study the structure of the molecular gas from
galactic scales (e.g. spiral arms) down to a single GMC. In particular we study
the correlations between the CO(1-0), IR and Radio Continuum emissions on
different spatial scales and investigate the physical processes behind these
observed correlations. In this talk, I will present the first results of such
an analysis and their consequences on star formation estimation within
the galactic disk. I will then review the other prospects of this ambitious
project, discussing in particular how high resolution mm observations (e.g.
with ALMA) will further the study of the interstellar medium
in nearby galaxies and its role in star formation.

We have performed axisymmetric hydrodynamic simulations black hole
fueling and feedback in a massive galaxy. The effects of the central
black hole on the temperature and momentum of galactic gas resulting
from both radiative and mechanical feedback (in the form of a
broad-line wind) are treated carefully using a detailed and physically
well-motivated prescription. The simulations cover a range of length
scales from ~1 pc to ~100 kpc. We carefully treat the forces on the
gas due to dust opacity in the UV, optical, and IR bands from photons
generated by both stars and the central AGN. We include a
prescription for angular momentum transport, allowing us to consider
galaxies with large specific angular momenta (disk galaxies) in the
axisymmetric code. We consider the case of including steady
cosmological infall of cold gas, as well as the case of the rapid
removal of the angular momentum of a cold gas disk to mimic the effect
of a galaxy merger. We find that the black hole accretion rate
depends strongly on the inner radius of the simulation, implying that
physical processes that operate on infalling gas between 1 and 100 pc
have an important effect on the true black hole accretion rate and the
resulting feedback processes.

Nearly 700 extrasolar planets have been detected so far and an intense
characterisation effort has been undertaken to unveil the atmospheric
properties of some of these distant worlds seen in transit accross
their stars. A large number of transiting exoplanets are found in extreme irradiation environments, very close to their stars, and the question arise
of whether the atmospheres of these planets remain stable or get blown away.
In particular, it is surmised that the recently detected rocky super-earths
(1-10 Earth masses) can be evaporation remnants of once more massive planets
completely eroded by the extreme stellar irradiation. Detecting the extended
atmospheres of exoplanets in different mass regimes and measuring their
mass loss rates and efficiencies are key steps towards the understanding of
the atmospheric dynamics and properties of low-mass exoplanets. I will review
the results we have obtained with HST on the atmospheric evaporation of
transiting exoplanets, on both observational and theoretical sides. Steping
back into the habitable zones, I will finally discuss the prospects about
atmospheric characterisation for Earth-size planets (such as Kepler-22b) and
how the upcoming transit of Venus in June 2012 could be a Rosetta stone to
interpret the future transmission spectra of Earth-like exoplanets that could
be obtained in the next decade."

It is established that stars form within molecular clouds via
gravitational collapse. I will present radiation-magneto-hydrodynamics
calculations of low-mass and massive dense core collapse, focusing on
the first collapse and the first hydrostatic core (first Larson core)
formation. The influence of magnetic field and initial mass on the
fragmentation properties will be investigated. In the first part,
I will briefly present the numerical method I use. In the second part
reporting low-mass dense core collapse calculations results,
synthetic observations of spectral energy distributions will be
derived, as well as classical observational quantities such as the
bolometric temperature and luminosity. I will show how the dust
continuum can help to target first hydrostatic cores and to state
about the nature of VeLLOs. Last, I will present synthetic
ALMA observation predictions of first hydrostatic cores which may
give an answer, if not definitive, to the fragmentation issue at
the early Class 0 stage.

In the third part, I will report the recent results of
radiation-magneto-hydrodynamics calculations in the context of
high mass star formation, using for the first time a self-consistent
model for photon emission (i.e. via thermal emission and in
radiative shocks) and with the high resolution necessary to resolve
properly magnetic braking effects and radiative shocks on scales
<100 AU (Commercon, Hennebelle & Henning ApJL 2011). In this study,
we investigate the combined effects of magnetic field, turbulence,
and radiative transfer on the early phases of the collapse and the
fragmentation of massive dense cores (M=100 Msun). We identify
a new mechanism that inhibits initial fragmentation of massive
dense cores, where magnetic field and radiative transfer interplay.
We show that this interplay becomes stronger as the magnetic field
strength increases. We speculate that highly magnetized massive
dense cores are good candidates for isolated massive star formation,
while moderately magnetized massive dense cores are more
appropriate to form OB associations or small star clusters.

I will present recent observational results obtained on the physics of
distant galaxies (~ 1<z<6) taking benefit of massive clusters used as
natural instruments. Gravitational magnification enables us to resolve
even the most distant objects, and to probe intrinsically fainter
sources at high redshift. This allows us to do the kind of research
that will only be achievable with the ELTs, but using
ground-based 8-10 m class telescopes and their current or
soon-forthcoming instruments. More precisely, after introducing
the topic and the use of massive clusters for their strong lensing
effect, I will present our ongoing work on strongly lensed LBGs in
the optical and near-infrared. In a second part, I will focus
on recent results obtained with Herschel, PdBI and SMA at
far-infrared / sub-mm and millimeter wavelengths, which enlarge
our panorama of the distant galaxy population.

After a spectacular birth, with the glow of the Big Bang fading away and the first atoms of hydrogen being formed, our Universe quickly became a dull place, with the first stars and galaxies yet to appear. How long these cosmic dark ages lasted and how they came to an end are questions of outmost importance in cosmology.
Based on recent theoretical and observational results, I will show that besides the ultraviolet radiation from primordial massive stars, X-rays and relativistic jets from their black hole fossils, must have played an important role at the dawn of the Universe. In this context, contrary to the prevailing view that the early Universe had a "Swiss-cheese"-like appearance that lasted several hundred million years, the dark ages may have had a smooth and fast end. These could be good news for the future probes of the dark ages by means of the redshifted 21 cm line of atomic hydrogen.

We currently have only a restricted picture of the star formation activity in
galaxies, partly because we don't have sufficient resolution to locate
properly sites of star formation beyond the Local Group. Interferometers such
as IRAM-PdBI, CARMA, SMA, and especillay ALMA now, are changing this picture.

In complement, I will show that we can actually improve our understanding of
the processes of star-formation in galaxies with single-dish telescopes, using
strategically key chemical tracers. More precisely, I will present work on the
determination of the ISM properties in local starburst, spirals, AGN-dominated
galaxies and early-type galaxies. Then, I will present some ISM properties in
'exotic' or more disturbed places such as in cosmic-ray dominated galaxies
and in cooling flows seen in the Perseus cluster.

I will also show some recent results acquired using interferometers enhancing
our knowledge to the finest scale possible today.

Using hydro-cosmological simulations and analytic modeling, we attempt solid
predictions for the formation of massive galaxies at high redshift within the
LCDM cosmology. The emerging picture highlights the formation of galaxies
at the nodes of the cosmic web. These galaxies are steadily fed by cold
streams along dark-matter filaments, which are observable in Lyman-alpha.
The streams, including a smooth component and merging galaxies, penetrate
through hot gas in dark-matter halos to form extended, turbulent, rotating
disks and bulges with central black holes. The streams transport angular
momentum from large distances into the disk that grows inside out, but a significant exchange of angular momentum occurs in the greater disk vicinity.
The intense gas input drives a self-regulated, violent gravitational disk
instability with transient features and giant clumps, where stars form rapidly.
The violent instability induces quick migration to the center, complementing
mergers as a mechanism for spheroid formation and for feeding AGN. We address
the implications of this developing picture on different aspects of galaxy
formation theory and its observable features.

La variété de galaxies dans le Groupe Local rend possible l'étude du milieu interstellaire et de la formation d'étoiles dans des conditions différentes de celles trouvées dans la Voie Lactée, tout en conservant une grande résolution spatiale grâce à leur proximité. Nous avons étudié le milieu interstellaire d galaxies du Groupe Local, M33 et NGC6822, dont les métallicités sont inférieur d'un facteur 2 à 3 à celle du soleil et qui sont respectivement dix fois et ce fois moins lumineuses que la Voie Lactée. Nos observations de la transition J=2- monoxyde de carbone, avec une résolution suffisante pour résoudre les nuages moléculaires géants, fournissent la première carte du milieu moléculaire de NG et la cartographie de M33 avec la meilleure combinaison de résolution et de sensibilité. Nous présentons également une cartographie haute résolution du mi atomique de M33 à partir d'une mosaïque intérférométrique dans la raie à 21cm l'ensemble du disque de la galaxie. Combinées avec des données allant de l'ultraviolet à l'infrarouge lointain, ces observations permettent l'étude du interstellaire et de la formation d'étoiles à des échelles allant du nuage individuel à la galaxie dans son ensemble. Ces deux objets, chimiquement jeun semblent convertir l'hydrogène moléculaire en étoiles plus rapidement que les grandes galaxies spirales comme la Voie Lactée. Est-ce à rapprocher du taux é de formation d'étoiles dans les galaxies de l'univers plus jeune (z~0.5-1), également riches en gaz et bleues comme M33 et NGC6822 ? Un soin particulier apporté pour tenter de mesurer la masse de dihydrogène, difficile dans ce type d'objet, à l'échelle de la galaxie ainsi qu'à l'échelle du nuage. Une méthode d'identification automatique et de mesure des propriétés physiques des nuages moléculaires géants a permis d'obtenir, dans le cas de M33, le plus grand cata de nuage moléculaires dans une galaxie extérieure. Il en résulte que les nuage M33 et de NGC 6822 ont, en moyenne, une largeur de raie plus faible, pour une donnée, que les nuages de la Voie Lactée. Dans M33, la fraction de petits nua augmente significativement avec le rayon galactocentrique. Au moins un sixièm nuages moléculaires géants ne sont pas associés à de la formation stellaire (détectée) mais nous n'avons pas identifié de caractéristiques physiques particulières pour ces nuages.

High spectral resolution allows us to discern the number of clouds along the line of
sight, their kinematics, the relative importance of turbulent motions, and chemical
signatures, including isotope ratios. Three recently completed projects will be
described. Absorption from atomic and molecular gas toward stars in the Pleiades
provided details of the interaction between the cluster and interstellar material.
It appears that the UV radiation from the stars has heated the gas sufficiently that
CH+ was formed in observable quantitites. In another study based on UV measuerments
with HST on CO and with FUSE on H2, the trends between CO abundance and H2 were
examined, as was the fractionation between 12C16O and 13C16O. The third study
involved 12 and 13 isotopoloques of CH+ and CN and the rotational temperatures of
12C14N and 13C14N. Here, we found that the 12CH+/13CH+ ratio appears to be
essentially constant within about a kpc of the Sun and that CN excitation
predomiantly arises from the Cosmic Background.

I will briefly describe the goals and strategy of the Atlas3D project
which targeted a complete volume-limited sample of 260 nearby early-type
galaxies. I will summarise the main (mostly published) results, and then
update the audience with the most recent advances obtained within the
context of that project: this leads us to a significantly revised view
of the nearby population of galaxies.

Since the appearance of General Relativity, its intrinsic general covariance has been very often misinterpreted as implying that physically meaningful quantities (and conclusions extracted from the theory) have to be absolutely independent on observers. This incorrect point of view is sometimes expressed by discarding the very concept of observer in the structure and applications of the theory. As we shall stress in this seminar, through some examples, the concept of observer is as essential to General Relativity as it is to any physical theory.

We studied the formation of water on dust grain analogs using isotopically labeled atomic hydrogen and oxygen beams. We detect the formation of water and intermediate products. As dust analogs, we used amorphous silicate films; for comparison, experiments done on a single crystal silicate were also carried out. The samples were characterized by in-situ infrared spectroscopy and ex-site atom force microscopy. Implications of these results on the formation of water in ISM environments will be discussed.

The Interstellar Medium is both the medium between the stars and the place of birth of the stars. At the Galactic scale, the ISM is best understood as a turbulent place. On smaller scales, the cold ISM, where stars form, is likely also turbulent. Words of caution arise from the lack of a definitive proof for the turbulent nature of the ISM which itself amounts to the lack of a complete theory of turbulence. Not only is the ISM turbulent: magnetic fields are now estimated strong enough to imprint their configuration on the cold matter distribution. If a theory of turbulence is still lacking, a theory of compressible, magnetized turbulence may seem unachievable. Even though, understanding turbulence in the cold ISM is required for a proper understanding of the cycle of matter in the ISM. The last decade has fostered direct numerical simulations of the physics of the ISM. Comparisons between theoretical predictions, numerical results, and observational constraints is becoming a tool to study the complex interplay of physics and chemistry in the ISM. I will review the general arguments that support a turbulent view of the ISM, with special emphasis towards the cold molecular ISM. Some consequences of turbulence in the ISM will be presented in the view of recent Herschel satellite results, whereas the Planck mission will provide constraints to the interplay between turbulence and magnetic fields. The soon-opening (extremely) high angular resolution era will certainly bring new constraints on fundamental questions regarding the nature of the interstellar turbulence and the structure of the ISM.

The last years impressively showed that to understand the assembly and formation of massive galaxies, it is critical to study Submillimeter Galaxies (SMGs). Since their first detection more than ten years ago, several hundred dust-enshrouded high-z sources have been selected through ground-based submm/mm imaging with bolometer cameras like SCUBA, LABOCA, AzTEC or MAMBO, opening a new exciting era in observational cosmology and giving an important route to investigate star formation and the formation of spheroids in the distant universe. One of the current key topics in galaxy formation and assembly is to obtain an accurate estimate of the number of SMGs at z>4, thus to get a complet census of the star-formation at the most distant redshifts and add missing bits on the obscured universe at extreme redshifts to the Lilly-Madau Plot. I will discuss different approaches to find dusty starbursts at redshifts beyond z=4 and present our on-going Herschel and IRAM efforts on this research topic. Finally, I will discuss the prospects of ALMA studies on dusty starbursts in the very high-z universe.

The Cornell University Laboratory of Plasma Studies makes use of 1 trillion watt, 1 million ampere pulsed power generators for fundamental studies and applications of high energy density plasmas in several configurations. Some are as high density and temperature as $10^{22}/cm^3$ and 1.5 keV, respectively, with very short life, $<<$ 1 ns. Others last as long as a few hundred nanoseconds at somewhat lower density and temperature and take the form of plasma jets that can interact with other plasmas. These have been used for studies of the interaction of plasma jets with a cross wind in a configuration with dimensionless parameters that are of interest to the astrophysics community. The very short-lived, hot plasma is an extremely bright x-ray source that has been used for x-ray absorption spectroscopy in high energy density plasmas and could be used to determine the radiation transfer properties of materials that make up such astrophysical objects as supernova remnants.

I will review the recent work conducted in the last year regarding the detection and study of the distant high-redshift (z>6) galaxies. Of particular importance is the recent installation of the WFC3 camera onboard of Hubble which InfraRed imaging channel is delivering the deepest images ever obtained in the 1-1.6 micron window. The new HST images are allowing to identify a large number of high redshift galaxy candidates that can then be follow-up in spectroscopy with 8-10m telescopes. I will discuss whether these findings can account from the reionization of the Universe, and what are the current observational limitations that can be improved with current and future facilities.
Please see http://www.spacetelescope.org/news/heic1106/