Related papers: QSO host galaxy star formation history from multic…
We present the first results from our population synthesis models of elliptical galaxies. In this paper, we concentrate upon the near-infrared region of the spectrum (0.7-3 um). We model elliptical galaxies as coeval, single-metallicity…
We use galaxy catalogues constructed by combining high-resolution N-body simulations with semi-analytic models of galaxy formation to study the properties of Long Gamma-Ray Burst (LGRB) host galaxies. We assume that LGRBs originate from the…
We present a deep UBI CCD survey using the Palomar 5-m telescope of a sample of high X-ray luminosity, distant clusters selected from the ROSAT All-Sky Survey. The 10 clusters lie at z=0.22-0.28, an era where evolutionary effects have been…
We examine the properties of the host galaxies of 22,623 narrow-line AGN with 0.02<z<0.3 selected from a complete sample of 122,808 galaxies from the Sloan Digital Sky Survey. We focus on the luminosity of the [OIII]$\lambda$5007 emission…
Large-scale surveys over the last years have revealed about 300 QSOs at redshift above 6. Follow-up observations identified surprising properties, such as the very high black hole (BH) masses, spatial correlations with surrounding cold gas…
We present submillimetre and mid-infrared imaging observations of five fields centred on quasi-stellar objects (QSOs) at 1.7<z<2.8. All 5 QSOs were detected previously at submillimetre wavelengths. At 850 (450) um we detect 17 (11)…
Machine learning techniques, specifically the k-nearest neighbour algorithm applied to optical band colours, have had some success in predicting photometric redshifts of quasi-stellar objects (QSOs): Although the mean of differences between…
We use the combined photometric SDSS + GALEX database to look for populations of luminous blue star-forming galaxies. These were initially identified from such a sample at redshifts near 0.4, using SDSS spectra. We make use of the colour…
We have obtained with the SUSI CCD camera on the ESO 3.5m NTT deep images in the BVRI bands of the field centered on the QSO BRI 1202-0725 ($z_{\it em}=4.694$). In the final combined frames the stellar images have FWHM of 1,1,0.6 and 0.65…
We present B-band imaging of 18 low redshift (z<0.3) BL Lac objects for which their host galaxies were previously resolved in the R-band and the near-infrared H-band. For a subset of the objects, also U- and V-band imaging is presented.…
Ground-based high spatial-resolution optical and near-IR imaging at BIHK' is presented for a complete sample of optically selected Palomar-Green QSOs which have infrared excesses at least as great as those of "warm" AGN-like ultraluminous…
We investigate the ability of hierarchical models of QSO formation and evolution to match the observed luminosity, number counts and spatial clustering of quasars at redshift z<2. These models assume that the QSO emission is triggered by…
We present the rest-frame UV and optical photometry and morphology of low-redshift broad-line quasar host galaxies from the Sloan Digital Sky Survey Reverberation Mapping project. Our sample consists of 103 quasars at $z<0.8$, spanning a…
We report an optical detection of an extended structure around a QSO at z=6.43 (CFHQSJ2329-0301, the highest redshift QSO currently known) in deep z' and z_r-band images of the Subaru/Suprime-Cam. After a careful PSF (QSO) subtraction, a…
We study the star formation histories (SFH) and stellar populations of 213 red and 226 blue nearly face-on low surface brightness disk galaxies (LSBGs), which are selected from the main galaxy sample of Sloan Digital Sky Survey (SDSS) Data…
Understanding the mechanisms that lead dense environments to host galaxies with redder colors, more spheroidal morphologies, and lower star formation rates than field populations remains an important problem. As most candidate processes…
We present new high-resolution near-infrared observations in the J,H and K bands, obtained to study the properties of Seyfert host galaxies. The dataset consists of images in the three bands of practically the entire CfA sample of Seyfert…
We measure the host galaxy properties of five quasars with $z\sim 1.6 - 3.5$ selected from SDSS and AEGIS, which fall within the JWST/HST CEERS survey area. A PSF library is constructed based on stars in the full field-of-view of the data…
A series of population models are designed to explore the star formation history of gas-rich, low surface brightness (LSB) galaxies. LSB galaxies are unique in having properties of very blue colors, low H$\alpha$ emission and high gas…
BVRI data for the majority of the objects of the RC catalogue with steep spectra and $m_R<24^m$ are presented. These data have been used to estimate colour redshifts and the age of stellar systems of host galaxies. By way of example of…