Related papers: The Evolution of Quasars
Major astrophysical questions related to the formation and evolution of structures, and more specifically of galaxy groups and clusters, will still be open in the coming decade and beyond: what is the interplay of galaxy, supermassive black…
This is a review of recent observational and theoretical developments related to accreting neutron stars and black holes in binary systems.
We have performed a search over 3440 deg$^2$ of Epoch 1 (2017-2019) of the Very Large Array Sky Survey to identify unobscured quasars in the optical ($0.2 < z < 3.2$) and obscured active galactic nuclei (AGN) in the infrared that have…
Since the discovery of active galactic nuclei (AGN) and their subclasses, a unification scheme of AGN has been long sought. Orientation-based unified models predict that some of the diversity within AGN subclasses can be explained by the…
Quasars at z>4 provide direct information on the first massive structures to form in the Universe. Recent ground-based optical surveys (e.g., the Sloan Digital Sky Survey) have discovered large numbers of high-redshift quasars, increasing…
Observational studies of AGN in the mid-infrared regime are crucial to our understanding of AGN and their role in the evolution of galaxies. Mid-IR-based selection of AGN is complementary to more traditional techniques allowing for a more…
Beyond all reasonable doubt, black holes are commonly found in the nuclei of most normal galaxies. In recent years, dynamical measurements of hole masses have transformed the study of their functioning and evolution. In particular, relating…
Over the last few years, optical, mid-infrared and X-ray surveys have brought to light a significant number of candidate obscured AGN and, among them, many Type 2 quasars, the long-sought after "big cousins'' of local Seyfert 2 galaxies.…
In this review I concentrate exclusively on models for the large-scale structure created by jet flows in AGN. I briefly mention models for the evolution and emission of these objects and how they can also be applied to microquasars. While…
In this paper we summarise the research that is currently going on in Ethiopia and East-Africa in extragalactic astronomy and physics of active galaxies and active galactic nuclei (AGN). The study is focused on some of the still open…
Black hole spins affect the efficiency of the "classical" accretion processes, hence the radiative output from quasars. Spins also determine how much energy is extractable from the hole itself. Recently it became clear that massive black…
Supermassive black holes (SMBHs) are nowadays believed to reside in most local galaxies, and the available data show an empirical correlation between bulge luminosity - or stellar velocity dispersion - and black hole mass, suggesting a…
Radio observations allow us to identify a wide range of active galactic nuclei (AGN), which play a significant role in the evolution of galaxies. Amongst AGN at low radio-luminosities is the 'radio-quiet' quasar (RQQ) population, but how…
We explore the connections between the evolving galaxy and AGN populations. We present a simple phenomenological model that links the evolving galaxy mass function and the evolving quasar luminosity function, which makes specific and…
Understanding stellar evolution and its effect on planetary systems is crucial for correctly interpreting the chemical constraints of exo-planetary material that can be given to us by white dwarfs. This article will describe how asteroids,…
Accreting compact objects are crucial to understand several important astrophysical phenomena such as Type Ia supernovae, gravitational waves, or X-ray and $\gamma$-ray bursts. In addition, they are natural laboratories to infer fundamental…
In order to relate the observed evolution of the galaxy stellar mass function and the luminosity function of active galactic nuclei (AGN), we explore a co-evolution scenario in which AGN are associated only with the very last phases of the…
The majority of bright distant quasars $(z {}^{>}_{\sim} 1)$ may form in massive mergers appearing in compact galaxy groups in/and young clusters. The expected tests are (i) large correlation signal for medium-$z$ QSOs $(1 < z < 2)$ and…
The change in the slope of the radio source counts suggests the emergence of a new population of radio galaxies at mJy and sub-mJy levels. Our understanding of such faint radio sources has advanced over the last decade through increasingly…
Observations of jets from quasars and other types of accreting black hole are briefly summarized. The importance of beaming and $\gamma$-ray observations for understanding the origin of these jets is emphasised. It is argued that both the…