English
Related papers

Related papers: Star Formation in Luminous LoBAL Quasars at 2.0<z<…

200 papers

We present an estimate of the optical luminosity function (OLF) of LOFAR radio-selected quasars (RSQs) at $1.4<z<5.0$ in the $9.3\:\textrm{deg}^{2}$ NOAO Deep Wide-field survey (NDWFS) of the Bo\"otes field. The selection was based on…

Astrophysics of Galaxies · Physics 2020-04-08 E. Retana-Montenegro , H. J. A. Röttgering

We present our ALMA Cycle 4 measurements of the [CII] emission line and the underlying far-infrared (FIR) continuum emission from four optically low-luminosity ($M_{\rm 1450} > -25$) quasars at $z \gtrsim 6$ discovered by the Subaru Hyper…

We present the results of EVN+MERLIN VLBI polarization observations of 8 Broad Absorption Line (BAL) quasars at 1.6 GHz, including 4 LoBALs and 4 HiBALs with either steep or flat spectra on VLA scales. Only one steep-spectrum source,…

Astrophysics · Physics 2009-11-13 Y. Liu , D. R. Jiang , T. G. Wang , F. G. Xie

Through the use of a High Band Antenna system, the Low Frequency Array Two-Meter Sky Survey (LoTSS) is an attempt to complete a high-resolution survey of the northern celestial sky. To date, thousands of radio sources have been classified…

Astrophysics of Galaxies · Physics 2021-06-04 Antonio Paris

We present a detailed study of a high-redshift iron low-ionization broad absorption line (FeLoBAL) quasar (SDSS1214 at $z = 1.046$), including new interferometric $^{12}$CO $J$=2-1 observations, optical through far-infrared photometry, and…

The uncharted territory of the high-redshift ($z\gtrsim3$) Universe holds the key to understand the evolution of quasars. In an attempt to identify the most extreme members of the quasar population, i.e., blazars, we have carried out a…

High Energy Astrophysical Phenomena · Physics 2020-07-22 Vaidehi S. Paliya , M. Ajello , H. -M. Cao , M. Giroletti , Amanpreet Kaur , Greg Madejski , Benoit Lott , D. Hartmann

We have observed 104 gravitationally-lensed quasars at $z\sim1-4$ with Herschel/SPIRE, the largest such sample ever studied. By targeting gravitational lenses, we probe intrinsic far-infrared (FIR) luminosities and star formation rates…

We have carried out a survey with the Chandra X-ray Observatory of a sample of 10 optically bright broad absorption line (BAL) QSOs. Eight out of ten sources are detected. The 6 brightest X-ray sources have only high ionization BALs…

Astrophysics · Physics 2009-11-06 Paul J. Green , Thomas L. Aldcroft , Smita Mathur , Belinda J. Wilkes , Martin Elvis

We present a derivation of the star formation rate per comoving volume of quasar host galaxies, derived from stacking analyses of far-infrared to mm-wave photometry of quasars with redshifts 0<z<6 and absolute I-band magnitudes…

We present $Chandra$ observations of seven broad absorption line (BAL) quasars at $z=0.863$-2.516 with redshifted BAL troughs (RSBALs). Five of our seven targets were detected by $Chandra$ in 4-13 ks exposures with ACIS-S. The $\alpha_{\rm…

High Energy Astrophysical Phenomena · Physics 2017-04-26 Ning-Xiao Zhang , W. N. Brandt , N. S. Ahmed , P. B. Hall , B. Luo , Scott F. Anderson , N. Filiz Ak , P. Petitjean , D. P. Schneider , Yue Shen , R. Srianand

With the recent release of large (i.e., > hundred million objects), well-calibrated photometric surveys, such as DPOSS, 2MASS, and SDSS, spectroscopic identification of important targets is no longer a simple issue. In order to enhance the…

We present the results from a survey of i-dropout objects selected from ~1550 deg^2 of multicolor imaging data from the Sloan Digital Sky Survey, to search for luminous quasars at z>5.8. Objects with i*-z*>2.2 and z*<20.2 are selected, and…

Using the radio observations by FIRST and NVSS, we build a sample of 151 radio variable quasars selected from the Sloan Digital Sky Survey Data Release 3 (SDSS DR3). Six (probably another two) among them are classified as broad absorption…

Astrophysics · Physics 2009-11-13 Hongyan Zhou , Tinggui Wang , Huiyuan Wang , Junxian Wang , Weimin Yuan , Yu Lu

Some optically selected quasars exhibit Mg II assoicated absorption lines (AALs), and its origin remains unclear. In this paper, we compile a sample of 1769 quasars, with or without Mg II AALs. Of which 1689 are Far-Infrared (FIR) detected…

Astrophysics of Galaxies · Physics 2025-03-13 Zhe-Geng Chen , Rui-Jing Lu , Zhi-Fu Chen , Wen-Qiang Liang , Xing-Long Peng , Jing Li , Wei-Rong Huang

The behaviour of fast radio bursts (FRBs) at radio frequencies <400 MHz is not well understood due to very few detections, with only two known sources detected below 300 MHz. Characterising low-frequency emission of FRBs is vital for…

High Energy Astrophysical Phenomena · Physics 2025-12-03 Pragya Chawla , Akshatha Gopinath , Ninisha Manaswini , Cees Bassa , Jason Hessels , Vlad Kondratiev , Daniele Michilli , Ziggy Pleunis

The star formation rate (SFR) is a key parameter in the study of galaxy evolution. The accuracy of SFR measurements at z~2 has been questioned following a disagreement between observations and theoretical models. The latter predict SFRs at…

We perform a survey of the X-ray properties of 41 objects from the WISE/SDSS selected Hyper-luminous (WISSH) quasars sample, composed by 86 broad-line quasars (QSOs) with bolometric luminosity $L_{Bol}\geq 2\times 10^{47}\,erg\, s^{-1}$, at…

We report detection of radio recombination line (RRL) H$_{40\alpha}$ toward 75 sources, with data obtained from ACA observations in the ATOMS survey of 146 active Galactic star forming regions. We calculated ionized gas mass and star…

We investigate C IV broad absorption line (BAL) variability within a sample of 46 radio-loud quasars (RLQs), selected from SDSS/FIRST data to include both core-dominated (39) and lobe-dominated (7) objects. The sample consists primarily of…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-19 C. A. Welling , B. P. Miller , W. N. Brandt , D. M. Capellupo , R. R. Gibson

We present the results of a CO line survey of 30 galaxies at moderate redshift (z \sim 0.2-0.6), with the IRAM 30m telescope, with the goal to follow galaxy evolution and in particular the star formation efficiency (SFE) as defined by the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 F. Combes , S. Garcia-Burillo , J. Braine , E. Schinnerer , F. Walter , L. Colina