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881. Spectra of lensed QSO PSOJ0147
ID:
ivo://CDS.VizieR/J/A+A/605/L8
Title:
Spectra of lensed QSO PSOJ0147
Short Name:
J/A+A/605/L8
Date:
21 Oct 2021
Publisher:
CDS
Description:
The gravitational lensing time delay method provides a one-step determination of the Hubble constant (H0) with an uncertainty level on par with the cosmic distance ladder method. However, to further investigate the nature of the dark energy, a H0 estimate down to 1% level is greatly needed. This requires dozens of strongly lensed quasars that are yet to be delivered by ongoing and forthcoming all-sky surveys. In this work we aim to determine the spectroscopic redshift of PSOJ0147, the first strongly lensed quasar candidate found in the Pan-STARRS survey. The main goal of our work is to derive an accurate redshift estimate of the background quasar for cosmography. To obtain timely spectroscopically follow-up, we took advantage of the fast-track service programme that is carried out by the Nordic Optical Telescope. Using a grism covering 3200-9600{AA}, we identified prominent emission line features, such as Ly{alpha}, NV, OI, CII, SiIV, CIV, and [CIII] in the spectra of the background quasar of the PSOJ0147 lens system. This enables us to determine accurately the redshift of the background quasar. The spectrum of the background quasar exhibits prominent absorption features bluewards of the strong emission lines, such as Ly{alpha}, NV, and CIV. These blue absorption lines indicate that the background source is a broad absorption line (BAL) quasar. Unfortunately, the BAL features hamper an accurate determination of redshift using the above-mentioned strong emission lines. Nevertheless, we are able to determine a redshift of 2.341+/-0.001 from three of the four lensed quasar images with the clean forbidden line [CIII]. In addition, we also derive a maximum outflow velocity of ~9800km/s with the broad absorption features bluewards of the CIV emission line. This value of maximum outflow velocity is in good agreement with other BAL quasars.
882. Spectra of lensed QSOs (SSAP)
ID:
ivo://org.gavo.dc/mlqso/q/q
Title:
Spectra of lensed QSOs (SSAP)
Short Name:
mlqso bidi ssa
Date:
27 Dec 2024 08:31:12
Publisher:
The GAVO DC team
Description:
An archive of optical and near-infrared spectra of strongly lensed quasars and the lensing galaxies. The spectra are resolved to about a few Ångstroms and are flux-calibrated. The spectra resulted from deblending the lensed images in bidimensional spectra available from the SSAP service for `ivo://org.gavo.dc/mlqso/q/s <http://dc.g-vo.org/mlqso/q/s/info>`_.
883. Spectra of 13 lensed quasars
ID:
ivo://CDS.VizieR/J/A+A/544/A62
Title:
Spectra of 13 lensed quasars
Short Name:
J/A+A/544/A62
Date:
21 Oct 2021
Publisher:
CDS
Description:
We provide single-epoch spectroscopic data for a sample of 13 lensed quasars. The sources have bolometric luminosities between 10^44.7-47.4^erg/s and black hole masses 10^7.6-9.8^M_{sun}. These spectra have been used to perform a systematic search for microlensing in the broad line region. The spectra have been deblended using the MCS advanced deconvolution technique. We provide the extracted and flux calibrated spectra, and the 2D deconvolved frames, separating the point-like emission from the extended emission (from the residual sky and from the lensing galaxy).
884. Spectra of molecular absorbers
ID:
ivo://CDS.VizieR/J/A+A/629/A128
Title:
Spectra of molecular absorbers
Short Name:
J/A+A/629/A128
Date:
21 Oct 2021
Publisher:
CDS
Description:
We use observations of chlorine-bearing species in molecular absorbers at intermediate redshifts to investigate chemical properties and ^35^Cl/^37^Cl isotopic ratios in the absorbing sightlines. Chloronium (H_2_Cl^+^) is detected along three independent lines of sight in the z=0.89 and z=0.68 molecular absorbers located in front of the lensed quasars PKS 1830-211 and B 0218+357, respectively. Hydrogen chloride (HCl) was observed only toward PKS 1830-211, and is found to be-have differently from H_2_Cl^+^. It is detected in one line of sight with an abundance ratio [H_2_Cl+]/[HCl]~1, but remains undetected in the other, more diffuse, line of sight, with a ratio [H_2_Cl^+^]/[HCl]>17. The absorption profiles of these two chlorine-bearing species are compared to other species and discussed in terms of the physical properties of the absorbing gas. Our findings are consistent with the picture emerging from chemical models where different species trace gas with different molecular hydrogen fraction. The ^35^Cl/^37^Cl isotopic ratios are measured in the different lines of sight and are discussed in terms of stellar nucleosynthesis.
885. Spectra of quasar narrow-line regions
ID:
ivo://CDS.VizieR/J/MNRAS/448/3354
Title:
Spectra of quasar narrow-line regions
Short Name:
J/MNRAS/448/3354
Date:
21 Oct 2021
Publisher:
CDS
Description:
In a single optical spectrum, the quasar narrow-line region (NLR) reveals low density, photoionized gas in the host galaxy interstellar medium, while the immediate vicinity of the central engine generates the accretion disk continuum and broad emission lines. To isolate these two components, we construct a library of high S/N optical composite spectra created from the Sloan Digital Sky Survey (SDSS-DR7). We divide the sample into bins of continuum luminosity and H{beta} FWHM that are used to construct median composites at different redshift steps up to 0.75. We measure the luminosities of the narrow-emission lines [NeV]{lambda}3427, [NeIII]{lambda}3870, [OIII]{lambda}5007, and [OII]{lambda}3728 with ionization potentials (IPs) of 97, 40, 35, and 13.6eV respectively. The high IP lines' luminosities show no evidence of increase with redshift consistent with no evolution in the AGN SED or the host galaxy ISM illuminated by the continuum. In contrast, we find that the [OII] line becomes stronger at higher redshifts, and we interpret this as a consequence of enhanced star formation contributing to the [OII] emission in host galaxies at higher redshifts. The SFRs estimated from the [OII] luminosities show a flatter increase with z than non-AGN galaxies given our assumed AGN contribution to the [OII] luminosity. Finally, we confirm an inverse correlation between the strength of the FeII{lambda}4570 complex and both the [OIII] EW (though not the luminosity) and the width of the H{beta} line as known from the eigenvector 1 correlations.
886. Spectrophotometry of 3CR lobe-dominated quasars
ID:
ivo://CDS.VizieR/J/AJ/130/23
Title:
Spectrophotometry of 3CR lobe-dominated quasars
Short Name:
J/AJ/130/23
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present results from optical spectrophotometry of 19 of the 25 lobe-dominated quasars in the 3CR complete sample. The optical spectra were obtained with the Hale 5m telescope at Palomar Observatory, using the blue and red CCDs of the Double Spectrograph, between 1984 and 1992. Additional data from the literature allow us to analyze broad UV/optical emission lines in all 25 objects (100% completeness), with a total of 191 broad-line measurements (far more than the 68 points in the preliminary results presented in the 2002 work of Hough et al., 2002AJ....123.1258H).
887. Spectroscopic follow-up of the QUBRICS quasars
ID:
ivo://CDS.VizieR/J/ApJS/250/26
Title:
Spectroscopic follow-up of the QUBRICS quasars
Short Name:
J/ApJS/250/26
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the results of the spectroscopic follow-up of the QUasars as BRIght beacons for Cosmology in the Southern Hemisphere (QUBRICS; Calderone+ 2019, J/ApJ/887/268) survey. The selection method is based on a machine-learning approach applied to photometric catalogs, covering an area of ~12400deg^2^ in the Southern Hemisphere. The spectroscopic observations started in 2018 and identified 55 new, high-redshift (z>=2.5), bright (i<=18) quasi-stellar objects (QSOs), with the catalog published in late 2019. Here we report the current status of the survey, bringing the total number of bright QSOs at z>=2.5 identified by QUBRICS to 224. The success rate of the QUBRICS selection method, in its most recent training, is estimated to be 68%. The predominant contaminant turns out to be lower-z QSOs at z<2.5. This survey provides a unique sample of bright QSOs at high z available for a number of cosmological investigations. In particular, carrying out the redshift drift measurements (Sandage Test) in the Southern Hemisphere, using the High Resolution Spectrograph at the 39m Extremely Large Telescope appears to be possible with less than 2500hr of observations spread over 30 targets in 25yr.
888. Spectroscopy in lens fields
ID:
ivo://CDS.VizieR/J/ApJ/641/169
Title:
Spectroscopy in lens fields
Short Name:
J/ApJ/641/169
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the first results from our spectroscopic survey of strong gravitational lens environments. Six of the eight lens galaxies in our sample belong to a poor group of galaxies, three of which are newly discovered here (those associated with BRI 0952-0115, MG 1654+1346, and B2114+022).
889. Spectroscopy of Damped Ly{alpha} (DLA) systems
ID:
ivo://CDS.VizieR/J/ApJ/769/54
Title:
Spectroscopy of Damped Ly{alpha} (DLA) systems
Short Name:
J/ApJ/769/54
Date:
21 Oct 2021
Publisher:
CDS
Description:
Using a sample of 100 H I-selected damped Ly{alpha} (DLA) systems, observed with the High Resolution Echelle Spectrometer on the Keck I telescope, we present evidence that the scatter in the well-studied correlation between the redshift and metallicity of a DLA is largely due to the existence of a mass-metallicity relationship at each redshift. To describe the fundamental relations that exist between redshift, metallicity, and mass, we use a fundamental plane description, which is described by the following equation: [M/H]=(-1.9+/-0.5)+(0.74+/-0.21)*log{Delta}v_90_-(0.32+/-0.06)*z. Here, we assert that the velocity width, {Delta}v_90_, which is defined as the velocity interval containing 90% of the integrated optical depth, traces the mass of the underlying dark matter halo. This description provides two significant improvements over the individual descriptions of the mass-metallicity correlation and metallicity-redshift correlation. Firstly, the fundamental equation reduces the scatter around both relationships by about 20%, providing a more stringent constraint on numerical simulations modeling DLAs. Secondly, it confirms that the dark matter halos that host DLAs satisfy a mass-metallicity relationship at each redshift between redshifts 2 through 5.
890. Spectroscopy of 120 emission-line ICRF2 candidates
ID:
ivo://CDS.VizieR/J/AJ/146/10
Title:
Spectroscopy of 120 emission-line ICRF2 candidates
Short Name:
J/AJ/146/10
Date:
21 Oct 2021
Publisher:
CDS
Description:
Continuing our program of spectroscopic observations of International Celestial Reference Frame (ICRF) sources, we present redshifts for 120 quasars and radio galaxies. Data were obtained with five telescopes: the 3.58m European Southern Observatory New Technology Telescope, the two 8.2m Gemini telescopes, the 2.5m Nordic Optical Telescope (NOT), and the 6.0m Big Azimuthal Telescope of the Special Astrophysical Observatory in Russia. The targets were selected from the International VLBI Service for Geodesy & Astrometry candidate International Celestial Reference Catalog which forms part of an observational very long baseline interferometry (VLBI) program to strengthen the celestial reference frame. We obtained spectra of the potential optical counterparts of more than 150 compact flat-spectrum radio sources, and measured redshifts of 120 emission-line objects, together with 19 BL Lac objects. These identifications add significantly to the precise radio-optical frame tie to be undertaken by Gaia, due to be launched in 2013, and to the existing data available for analyzing source proper motions over the celestial sphere. We show that the distribution of redshifts for ICRF sources is consistent with the much larger sample drawn from Faint Images of the Radio Sky at Twenty cm (FIRST) and Sloan Digital Sky Survey, implying that the ultra-compact VLBI sources are not distinguished from the overall radio-loud quasar population. In addition, we obtained NOT spectra for five radio sources from the FIRST and NRAO VLA Sky Survey catalogs, selected on the basis of their red colors, which yielded three quasars with z>4.