Related papers: The 2dF BL Lac Survey II
We present the second report of our systematic search for strongly lensed quasars from the data of the Sloan Digital Sky Survey (SDSS). From extensive follow-up observations of 136 candidate objects, we find 36 lenses in the full sample of…
High-energy observations of extreme BL Lac objects, such as 1ES0229+200 or 1ES 0347-121, recently focused interest both for blazar and jet physics and for the implication on the extragalactic background light and intergalactic magnetic…
We identify and investigate the nature of the 20 brightest 250-micron sources detected by the BLAST within the central 150 sq. arcmin of the GOODS-South field. Aided by the available deep VLA radio imaging, reaching S_1.4 = 30 micro-Jy, we…
We present an analysis of 152,355 radio sources identified in the second data release of the LOFAR Two Metre Sky Survey (LoTSS-DR2) with Sloan Digital Sky Survey (SDSS) spectroscopic redshifts in the range 0.00 < z < 0.57. Using Monte Carlo…
Compact symmetric objects (CSOs) are intrinsically compact extragalactic radio sources that are thought to be the progenitors of classical radio galaxies. To date, evolutionary models have mainly focused on the formation and growth of…
We have used the VLA FIRST survey and the APM catalog of the POSS-I plates as the basis for constructing a new radio-selected sample of optically bright quasars. This is the first radio-selected sample that is competitive in size with…
The second catalog of active galactic nuclei (AGNs) detected by the Fermi Large Area Telescope (LAT) in two years of scientific operation is presented. The Second LAT AGN Catalog (2LAC) includes 1017 gamma-ray sources located at high…
We present the results of near-infrared H band (1.65 microns) imaging of 11 BL Lac objects with redshifts ranging from z = 0.05 to 0.9. We are able to clearly detect the host galaxy in seven low redshift (z<=0.24) BL Lacs, while the four…
The results of a search for peculiar astronomical objects using very low resolution spectra obtained with the NASA Orbital Debris Observatory (NODO) 3 meter diameter liquid mirror telescope (LMT) are compared with results of spectra…
We have built a sample of 74 radio-selected broad absorption line quasars from the Sloan Digital Sky Survey Data Release 5 (SDSS DR5) and Faint Images of the Radio Sky at Twenty Centimeters (FIRST), along with a well matched sample of 74…
Recent X-ray surveys with Chandra and XMM-Newton have found several genuine Type II quasars, the long sought-after population of high-luminosity (high-redshift) Seyfert 2 galaxies, and a sizable number of Type II quasar candidates. However,…
We present new measurements of the luminosity function (LF) of Luminous Red Galaxies (LRGs) from the Sloan Digital Sky Survey (SDSS) and the 2dF-SDSS LRG and Quasar (2SLAQ) survey. We have carefully quantified, and corrected for,…
We investigate the nature of low-luminosity radio-loud active galactic nuclei (RLAGN) selected from the LOFAR Two-metre Sky Survey (LoTSS) first data release (DR1). Using optical, mid-infrared, and radio data, we have conservatively…
The 2 cm VLBA Survey observed since 1994 a set of ~170 Quasars, BL Lac objects, and radio galaxies, selected to be representative of the compact AGN radio population. This effort was continued as the MOJAVE project, where a statistically…
New linear polarization measurements (mainly in the V band) are presented for 203 quasi-stellar objects (QSOs). The sample is made up of 94 QSOs located in the North Galactic Pole (NGP) region and of 109 QSOs in the South Galactic Pole…
We are carrying out sensitive X-ray observations with Chandra and XMM of type II quasars selected from the Sloan Digital Sky Survey based on their optical emission line properties. We present observations of four objects at redshifts 0.4 <…
Optically luminous quasars at $z > 5$ are important probes of super-massive black hole (SMBH) formation. With new and future radio facilities, the discovery of the brightest low-frequency radio sources in this epoch would be an important…
Spatially extended Ly-alpha sources which are faint and compact in coninuum are candidates for extremely young galaxies (age of ~<10e+7 yrs) at high redshifts. We carried out a systematic survey for extended Ly-alpha sources, using deep…
We present the spectroscopic analysis of a large sample of late-M, L, and T dwarfs from UKIDSS. Using the YJHK photometry from ULAS and the red-optical photometry from SDSS we selected a sample of 262 brown dwarf candidates and we…
We spectroscopically detected 838 likely, 448 probable, and 265 possible strong lens candidates within $\approx2$ million galaxy spectra contained within the extended Baryon Oscillation Spectroscopic Survey (eBOSS) from the sixteenth data…