相关论文: A mixture evolution scenario of the AGN radio lumi…
A key question in extragalactic astronomy is how the star-formation rate density (SFRD) evolves over cosmic time. A powerful way of addressing this question is using radio-continuum observations, where the radio waves are unaffected by dust…
We use new near-infrared spectroscopic observations to investigate the nature and evolution of the most luminous H\alpha (Ha) emitters at z~0.8-2.23, which evolve strongly in number density over this period, and compare them to more typical…
We have measured the luminous AGN population in a large sample of clusters of galaxies and find evidence for a substantial increase in the cluster AGN population from z~0.05 to z~1.3. The present sample now includes 32 clusters of galaxies,…
GPS and CSS radio sources are the objects of choice to investigate the evolution of young radio-loud AGN. Previous investigations, mainly based on number counts and source size distributions, indicate that GPS/CSS sources decrease…
The synthesis model for the cosmic X-ray background (XRB) -based on the integrated emission of Active Galactic Nuclei (AGNs)- is complemented with new observational results. We adopt the most recent estimates of the AGN X-ray luminosity…
We present a multi-wavelength study into the nature of faint radio sources in a deep radio image with the Giant Meterwave Radio Telescope at 612\,MHz covering 1.2 deg$^2$ of the ELAIS N1 region. We detect 2800 sources above…
The unification of active galactic nuclei (AGN) is a model that has been difficult to test due to the lack of knowledge on the intrinsic luminosities of the objects. We present a test were we probe the model by statistical investigation of…
We have formed a new sample which consists of extended extragalactic radio sources without obvious active galactic nuclei (AGN) in them. Most of these sources appear to be dead double radio sources. These sources with steep spectra ($\alpha…
Using deep observations across three of the LOFAR Two-metre Sky Survey Deep Fields, this work measures the angular clustering of star forming galaxies (SFGs) and low-excitation radio galaxies (LERGs) to $z$$\lesssim$1.5 for faint sources,…
The impact of active galactic nuclei (AGN) on the evolution of galaxies explains the steep decrease in the number density of the most massive galaxies in the Universe. However, the fueling of the AGN and the efficiency of this feedback…
Emission line diagnostic diagrams probing the ionization sources in galaxies, such as the Baldwin-Phillips-Terlevich (BPT) diagram, have been used extensively to distinguish AGN from purely star-forming galaxies. Yet, they remain poorly…
The XLF of AGN offers a robust tool to study the evolution and the growth of SMBHs over cosmic time. Owing to the limited area probed by X-ray surveys, optical surveys are routinely used to probe the accretion in the high redshift Universe…
The cosmic X-ray background (XRB) spectrum and active galaxy number counts encode essential information about the spectral evolution of active galactic nuclei (AGNs) and have been successfully modeled by XRB synthesis models for many years.…
Analysis of the frequency and physical properties of galaxies with star-formation and AGN activity in different environments in the local universe is a cornerstone for understanding structure formation and galaxy evolution. We have built a…
The simple unification scheme of powerful radio galaxies and quasars, based entirely on the orientation dependent effects, has been confronted with the observed radio structures for 152 radio galaxies and 173 steep spectrum quasars.…
We have combined optical data from the 2dF-SDSS Luminous Red Galaxy and QSO (2SLAQ) redshift survey with radio measurements from the 1.4 GHz VLA FIRST and NVSS surveys to identify a volume-limited sample of 391 radio galaxies at redshift…
Aims. We investigate the radio loudness ($\mathcal{R}$) distribution in a large, homogeneous sample of radio galaxies. Methods. The sample is composed of galaxies from the ROGUE I/II catalogue belonging to the SDSS MGS and is divided into…
We present a catalog of 213 type-2 AGN selected from the zCOSMOS survey. The selected sample covers a wide redshift range (0.15<z<0.92) and is deeper than any other previous study, encompassing the luminosity range 10^{5.5} < Lsun< L[OIII]…
Several lines of argument support the existence of a link between activity at the nuclei of galaxies, in the form of an accreting supermassive black hole, and star-formation activity in these galaxies. The exact nature of this link is still…
Galaxy clusters grow by a sequence of mergers with other clusters and galaxy groups. During these mergers, shocks and/or turbulence are created within the intracluster medium (ICM). In this process, particles could be accelerated to highly…