相关论文: Quasars
Over the past several decades, advances in telescope/detector technologies and deep imaging techniques have pushed surface brightness limits to ever fainter levels. We can now both detect and measure the diffuse, extended star light that…
The purpose of this contribution is to review the current status of black hole demographics in light of recent advances in the study of high redshift QSOs (section 2), local AGNs (section 3) and local quiescent galaxies (section 4). I will…
The impact of quasars on their galaxy neighbours is an important factor in the understanding of galaxy evolution models. The aim of this work is to characterize the intermediate-scale environments of quasars at low redshift (z $<$ 0.2) with…
This is a pedagogical review of recent results on the interactions of central massive black holes with stars very near them, focused on the black hole in the center of the Milky Way. Table of contents: [1] Introduction [2] Stellar dynamics…
The symposium has shown the dynamism of this rapidly evolving discipline. I shall concentrate here on some highlights and some complementary informations. I conclude on open questions with some perspectives on solar & stellar activity and…
This summary discusses new results on the stellar and gaseous luminous halo, and on the dark halo. It concludes with a look towards the future, with emphasis on the role of space astrometry missions.
We present near-infrared imaging obtained with ESO VLT/ISAAC of a sample of 16 low luminosity radio-quiet quasars at the epoch around the peak of the quasar activity (2 < z < 3), aimed at investigating their host galaxies. For 11 quasars,…
Quasars have reigned as the most luminous and distant objects in the Universe. These concepts were based on the hypothesis that the redshifts of quasars are obeying the Hubble low. This hypothesis has little serious competition today, but…
This review discusses the current status of supermassive black hole research, as seen from a purely observational standpoint. Since the early '90s, rapid technological advances, most notably the launch of the Hubble Space Telescope, the…
I review the current data on abundances in irregular galaxies, with special emphasis on recent results on C/O and Si/O from observations with the Hubble Space Telescope. The abundance data for He, C, N, and O in irregular galaxies is…
Quasar-galaxy associations, if they result from the effect of gravitational lensing by foreground galaxies, depend sensitively on the shape of the quasar number counts. Two kinds of quasar number-magnitude relations are predicted to produce…
Whether or not $z \gtrsim 6$ quasars lie in the most massive dark-matter halos of the Universe is still a subject of dispute. While most theoretical studies support this scenario, current observations yield discordant results when they…
We investigate the hypothesis that quasars formed together with the stellar populations of early-type galaxies. This hypothesis, in conjunction with the stellar ages of early-type galaxies from population synthesis models, the relation of…
We consider the key problems related to measuring the mass of stellar disks and dark halos in galaxies and to explaining the observed properties of disks formed in massive dark halos.
The observational evidence for jets and phenomena arising from rotation powered radio pulsars is reviewed, including many recent and exciting discoveries at X-ray wavelengths. The well studied jets of the Crab pulsar are summarised,…
I review the observational side of the present state of the debate about the dark matter in galaxies, with emphasis on the core/cusp problem in low surface brightness galaxies, and the question of maximum / sub-maximum disks in spiral…
Much progress has been made in measuring black hole (BH) masses in (non-active) galactic nuclei using the tight correlation between stellar velocity dispersions (sigma) in galaxies and the mass of their central BH. The use of this…
Weak gravitational lensing has become an important tool to study the properties of dark matter halos around galaxies, thanks to the advent of large panoramic cameras on 4m class telescopes. This area of research has been developing rapidly…
The nature of dark energy, driving the accelerated expansion of the Universe, is one of the most important issues in modern astrophysics. In order to understand this phenomenon, we need precise astrophysical probes of the universal…
In the past years, the results obtained by the WISSH quasar project provided a novel general picture on the distinctive multi-band properties of hyper-luminous ($L_{bol}>10^{47}$ erg/s) quasars at high redshift (z$\sim$2-4), unveiling…