Related papers: Hidden AGNs in Early-Type Galaxies
We use the INTEGRAL all-sky hard X-ray survey to perform a statistical study of a representative sample of nearby AGN. Our entire all-sky sample consists of 127 AGN, of which 91 are confidently detected (>5 sigma) on the time-averaged map…
Using the 1 Ms Chandra Deep Field North and 15 micron ISOCAM HDF-N surveys we find a tight correlation between the population of strongly evolving starbursts discovered in faint 15 micron ISOCAM surveys and the apparently normal galaxy…
We present a thorough characterization of a large sample of 183 extreme emission-line galaxies (EELGs) at redshift 0.11 < z < 0.93 selected from the 20k zCOSMOS Bright Survey because of their unusually large emission line equivalent widths.…
We study the evolutionary trend of the total density profile of early-type galaxies (ETGs) in IllustrisTNG. To this end, we trace ETGs from $z=0$ to $z=4$ and measure the power-law slope $\gamma^{\prime}$ of the total density profile for…
We have analyzed Chandra observations of 18 low-luminosity early-type galaxies with L_B < 3 x 10e10 Lo. Thermal emission from hot gas with temperatures between 0.2 and 0.8 keV comprises 5-70% of the total 0.5-2.0 keV emission from these…
We combine deep X-ray survey data from the Chandra observatory and the wide-area/shallow XMM-XXL field to estimate the AGN X-ray luminosity function in the redshift range z=3-5. The sample consists of nearly 340 sources with either…
We present a study of the overdensity of X-ray selected AGN in 33 galaxy clusters in the XMM-LSS field, up to redhift z=1.05. Previous studies have shown that the presence of X-ray selected AGN in rich galaxy clusters is suppressed. In the…
We discuss preliminary results from our programme to map the fields of high-redshift AGN. In the context of the hierarchical models such fields are predicted to contain an over-density of young, luminous galaxies destined to evolve into the…
We investigate the evolution of the hard X-ray luminosity of the red galaxy population using a large sample of 3316 red galaxies selected over a wide range in redshift (0.3<z<0.9) from a 1.4 deg^2 region in the Bootes field of the NOAO Deep…
We study properties of the host galaxies of 15 hard X-ray selected type-2 active galactic nuclei (AGNs) at intermediate redshifts (0.05$<z<$0.6) detected in $ASCA$ surveys. The absorption corrected hard X-ray luminosities $L_{\rm 2-10 keV}$…
We searched in the public archive of the Chandra X-ray Observatory as of March 2016 and assembled a sample of 719 galaxies within 50 Mpc with ACIS observations available. By cross-correlation with the optical or near-infrared nuclei of…
Hierarchical galaxy formation models predict the development of elliptical galaxies through a combination of the mergers and interactions of smaller galaxies. We are carrying out a study of Early-Type Galaxies (ETGs) using GAMA…
We present constraints on the formation and evolution of early-type galaxies (ETGs) with the empirical model EMERGE. The parameters of this model are adjusted so that it reproduces the evolution of stellar mass functions, specific star…
We constrain the X-ray emission properties of Lyman break galaxies (LBGs) at z ~ 3-6 using the 2 Ms Chandra Deep Field-North and 1 Ms Chandra Deep Field-South. Large samples of LBGs were discovered using HST as part of the Great…
We present a comprehensive analysis of the X-ray spectral properties of 198 newly identified active galactic nuclei (AGNs), leveraging archival data from the {\it Chandra} X-ray Observatory. All these AGNs exhibit a powerlaw spectral…
We present X-ray spectra of four ultraluminous infrared galaxies (ULIRGs) with detectable broad near-infrared emission lines produced by active galactic nuclei (AGNs): Mrk 463, PKS 1345+12, IRAS 05189-2524, and IRAS 07598+6508. With the…
The four-year X-ray all-sky survey (eRASS) of the eROSITA telescope aboard the Spektrum-Roentgen-Gamma satellite will detect ~3 million active galactic nuclei (AGN) with a median redshift of z~1 and a typical luminosity of L_(0.5-2.0 keV) ~…
A recent determination of the relationships between the X-ray luminosity of the ISM (Lx) and the stellar and total mass, for a sample of nearby early-type galaxies (ETGs), is used to investigate the origin of the hot gas, via a comparison…
The emission from individual X-ray sources in the Chandra Deep Fields and XMM-Newton Lockman Hole shows that almost half of the hard X-ray background above 6 keV is unresolved and implies the existence of a missing population of heavily…
We present broadband properties of sources in the Chandra Deep Field-North with spectroscopic redshifts. The high luminosity and redshift bins are dominated by typical quasars. The intermediate redshift (z = 0.7-1.5) and luminosity ranges…