Several AGNs have been reported to have ultra-high velocity (UHV) outflows (of order 0.3 ≳ ν/c ≳ 0.05) that are detected in their X-ray spectrum. Re-visiting these outflow observations reveal that the spectrum has changed along with the claimed outflows. The luminous quasar PDS 456 is the brightest AGN in which a UHV outflow has been claimed to be present in its grating spectrum. We report on an XMM–Newton observation of this source, as well as analysis of past observations, which reveal its variable nature and the variable nature of UHV outflows. In this object, as well as in a few others, repeated observations failed to reproduce the previous absorption spectra. This indicates that variability is common among the UHV winds. A discussion of the reality, significance, and the interpretation of the UHV outflow phenomenon is presented. If UHV outflows exist, they might be a transiting phenomenon, as indicated from repeated observations, and this has to be taken into account when studying the influence of these outflows on the surrounding galaxy.

The Joint Discussion on the variability of fundamental constants within the IAU GA 2009 was organized with the coordination of the IAU Division VIII Galaxies & the Universe and the support of IAU Commissions N. 47 Cosmology, N. 52 Relativity in Fundamental Astronomy, N.40 Radio Astronomy and N. 30 Radial velocities. The JD provided a timely opportunity to confront different points of view on this rather exciting subject.

We summarize the latest results of an ongoing project aimed at connecting starburst galaxies in the local Universe and Lyman-break galaxies (LBGs) in the distant Universe using rest-frame ultraviolet (UV) images. We are quantifying star formation in the local Universe using GALEX data of interacting galaxies and we are using Hubble Space TelescopeU-band and optical images of the Ultra Deep Field to quantify star formation at intermediate (z ~ 1) and high (z > 2) redshifts, respectively. We are measuring sizes of star-forming clumps in all redshift ranges and searching for evolutionary effects. We chose the rest-frame UV to do this work because young and massive stars radiate most their energy in the UV and also because LBGs are selected to be UV-bright. We discuss whether all galaxies go through an LBG phase and whether disks show any sign of size of evolution at z < 1.

Astronomy is perhaps the best example of fundamental research aiming to increase our knowledge well beyond our human neighborhood. But astronomy is also a Big Science, which is partly technology-driven. Progress in observational capabilities is due to progress in detectors, telescopes, satellites, etc. I use three examples –radio astronomy, adaptive optics and detectors– to describe the complex interactions between astronomy, technology development and industry. I conclude by a short description of the global economic impact of astronomy.

Including MIPS 24 μm dust emission in the multi-band stellar population analysis, we roughly constrain the star formation histories (SFHs) of MIPS 24 μm selected star-forming regions across the merging disks of the Antennae galaxies. While the overlap regions hold the highest ratios of young over intermediate populations, the western-loop regions have the highest ratios of intermediate to old populations. We find two sequential star formation (SF) paths in the overlap regions, which we interpret as the imprint of the interpenetrating process of the two merging disks following their second close encounter.

We have carried out a large observational study of the radio luminosities, stellar populations, and environments of massive galaxies over the redshift range 0 < z < 1. Radio jets powered by an accreting central black hole are common in massive galaxies, and there is a large class of “optically quiet AGN,” with radio emission but no optical/IR signature of black-hole accretion. The central black holes in these galaxies are probably accreting in a radiatively inefficient mode, and our results suggest that “radio-mode feedback” as described by Croton et al. is likely to occur in all masssive early-type galaxies at z < 0.8. While it appears that radio-loud AGN occur episodically in all massive early-type galaxies, we also identify a sub-population of galaxies with powerful radio sources and a prominent younger (~ 108 yr) stellar population that may have undergone recent mergers.

In many theories of unified interactions, there are additional degrees of freedom which may allow for the variation of the fundamental constants of nature. I will review the motivation for such variations, and describe the theoretical relations between variations of gauge and Yukawa couplings.

We present results from a catalogue of 1696 X-ray point sources detected in the massive star-forming region Cygnus OB2, the majority of which have optical or near-infrared associations. We derive ages of 3.5 and 5.25 Myr for the stellar populations in our two fields, in agreement with recent studies that suggest that the central 1–3 Myr-old OB association is surrounded and contaminated by an older population with an age of 5–10 Myr. The fraction of sources with protoplanetary disks, as traced by K-band excesses, is unusually low. Although this has previously been interpreted as due to the influence of the large number of OB stars in Cyg OB2, contamination from an older population of stars in the region could also be responsible. An initial mass function is derived and found to have a slope of Γ = −1.27, in agreement with the canonical value. Finally, we introduce the recently approved Chandra Cygnus OB2 Legacy Survey that will image a 1 square degree area of the Cygnus OB2 association to a depth of 120~ks, likely detecting ~ 10 000 stellar X-ray sources.

The spectra of AGN, from the ultraviolet to the near infrared, exhibit emission lines covering a wide range of ionization states, from neutral species such as [O i] λ 6300, up to [Fe iv] λ 5303. Here we report on some recent studies of the properties of highly ionized lines (HILs), plus two case studies of individual objects. Future IFU observations at high spatial and good spectral resolution will probe the excitation and kinematics of the gas in the zone between the extended NLR and unresolved BLR. Multi-component SED fitting can be used to link the source of photoionization with the strengths and ratios of the HILs.

This R&D project implements a new way of perception of the three-dimensional surrounding space, based exclusively in sounds and thus especially useful for the blind. The innate capability of locating sounds, the externalization of sounds played with headphones and the machine capture of the 3D environment are the technological pillars used for this purpose. They are analysed and a summary of their main requirements are presented. A number of laboratory facilities and portable prototypes are described, together with their main characteristics.

Super star clusters (SSCs) are young massive objects typically observed in starburst galaxies. They consist of millions of stars occupying volumes only several parsecs across. Recent infrared observations of SSCs reveal strong emission lines with moderately supersonic widths (FWHM ~ 50 – 100 km s−1). An additional, much broader and weaker line component is present in some cases. Using 2D and 3D hydrodynamic simulations, we study models of SSCs in the so-called bimodal regime, which occurs if the stellar density inside the cluster exceeds a certain limit. We confirm the existence of the bimodal solution predicted analytically and suggest an explanation for double-component line profiles: the narrow component is formed close to the cluster center by repressurizing shocks compressing the rarefied gas cooled down due to the thermal instability into dense cold clumps, while the broad component is created by the wind, which cools down at a certain distance from the cluster.

We present a study of the radial velocity offsets between AGN-related narrow emission lines and host-galaxy emission and absorption lines in Seyfert galaxies with observed redshifts less than 0.043. We find that 35% of the Seyferts in the sample show [O iii] emission lines with blueshifts with respect to their host galaxies exceeding 50 km s−1, whereas only 6% show redshifts this large, in qualitative agreement with most previous studies. We also find that a greater percentage of Seyfert 1 galaxies show blueshifts than Seyfert 2 galaxies. Using HST/STIS spatially-resolved spectra of the Seyfert 2 galaxy NGC 1068 and the Seyfert 1 galaxy NGC 4151, we generate geometric models of their narrow-line regions (NLRs) and inner galactic disks and show how these models can explain the blueshifted [O iii] emission lines in collapsed STIS spectra of these two Seyferts. We conclude that the combination of mass outflow of ionized gas in the NLR and extinction by dust in the inner disk (primarily in the form of dust spirals) is primarily responsible for the velocity offsets in Seyfert galaxies.

Variable speed of light theories (VSL) are interesting because they could solve several cosmological puzzles. In this work we study the thermodynamics and Newtonian limit of the varying speed of light theory developed by J. Magueijo (Magueijo 2000). In the covariant and locally Lorentz invariant VSL proposed by Magueijo c is a dimensionless dynamical scalar field c=c0eψ, where c0 is a constant. The matter and gravitational lagrangians are multiplied by the factors ebψ and eaψ respectively.

This is about the relationship between technology and astronomy, and in particular about people in astronomy getting into the hi-tech world. These people might be graduate students looking for jobs, they might be fully fledged academics wanting to exploit their know-how. Whichever it is, it is essential to understand the differences between these two worlds and especially to understand that the hi-tech world only wants you for what you can bring to the table. So welcome to “the hi-tech party”.

I start with assuming a gravitational scalar field as the dark-energy supposed to be responsible for the accelerating universe. Also from the point of view of unification, a scalar field implies a time-variability of certain “constants” in Nature. In this context I once derived a relation for the time-variability of the fine-structure constant α: Δα/α =ζ Ƶ(α/π) Δσ, where ζ and Ƶ are the constants of the order one, while σ on the right-hand side is the scalar field in action in the accelerating universe. I use the reduced Planckian units with c=ℏ =MP(=(8π G)−1/2)=1. I then compared the dynamics of the accelerating universe, on one hand, and Δα/α derived from the analyses of QSO absorption lines, Oklo phenomenon, also different atomic clocks in the laboratories, on the other hand. I am here going to discuss the theoretical background of the relation, based on the scalar-tensor theory invented first by Jordan in 1955.

The motion of a black hole (BH) induces a strong response from the surrounding stellar population. We recall the case of an analytical harmonic potential where half of the stars on circular orbits in that potential shift to an orbit of lower energy, while the other half receive a positive boost and recede to a larger radius. The black hole itself remains on an orbit of fixed amplitude and merely acts as a catalyst for the evolution of the stellar energy distribution function f(E). Numerical integration with a response code show that this effect is operative out to a radius of ~3 to 4 times the radius of influence of the BH RBH. The results for the kinematic signature of BH motion are not sensitive to the shape of the potential and the temperature of the stars measured with Toomre's Q parameter. We report on the evolution of fully self-gravitating systems when damping of the BH orbit is way off the expected exponential decay obtained from the Chandrasekhar formula, a possible result from energy exchanges with the background stars.

Following the celebrated DVD, Gathering the Forgotten Voices, we have embarked on new interviews of the men and women whose hard work and ingenuity forged the technological breakthroughs that maintained CFHT's preeminence as a world-class observatory. While Gathering the Forgotten Voices emphasized the personal history of those involved with the first decade of deep-space observing, the new DVD explores the CFHT innovation in instrumentation from vision through design to construction. It will chronicle the breakthroughs of the observatory's staff so that that record may serve as a prototype for qualitative research at other technological centers.

The presence of blue straggler stars (BSs) as secure members of star clusters poses a major challenge to the conventional picture of simple stellar population (SSP) models. The models are based on the stellar evolution theory of single stars, while the major formation mechanisms of BSs are all correlated with stellar interactions. Based on a sufficient working sample including 100 Galactic open clusters, one Galactic globular cluster, and seven Magellanic Cloud star clusters, we discuss the modifications of the properties of broad-band colors and Lick indices of the standard SSP models due to BS populations.