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1961. The 2dF QSO Redshift Survey. VIII
ID:
ivo://CDS.VizieR/J/MNRAS/328/805
Title:
The 2dF QSO Redshift Survey. VIII
Short Name:
J/MNRAS/328/805
Date:
21 Oct 2021
Publisher:
CDS
Description:
We examine the highest signal-to-noise ratio spectra from the 2dF QSO Redshift Survey (2QZ) 10k release (Cat. <VII/223>) and identify over 100 new low-ionization heavy-element absorbers: damped Lyman-{alpha} (DLA) candidates suitable for higher-resolution follow-up observations. These absorption systems map the spatial distribution of high-z metals in exactly the same volumes as the foreground 2QZ QSOs themselves sample and hence the 2QZ gives us the unique opportunity to compare directly the two tracers of large-scale structure. We examine the cross-correlation of the two populations to see how they are relatively clustered, and, by considering the colour of the QSOs, detect a small amount of dust in these metal systems.
1962. The 2dF-SDSS QSO survey
ID:
ivo://CDS.VizieR/J/MNRAS/392/19
Title:
The 2dF-SDSS QSO survey
Short Name:
J/MNRAS/392/19
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the final spectroscopic QSO catalogue from the 2dF-SDSS LRG (luminous red galaxy) and QSO (2SLAQ) survey. This is a deep, 18<g<21.85 (extinction corrected), sample aimed at probing in detail the faint end of the broad line active galactic nuclei luminosity distribution at z<=2.6. The candidate QSOs were selected from SDSS photometry and observed spectroscopically with the 2dF spectrograph on the Anglo-Australian Telescope. This sample covers an area of 191.9 deg2 and contains new spectra of 16326 objects, of which 8764 are QSOs and 7623 are newly discovered [the remainder were previously identified by the 2dF QSO Redshift Survey (2QZ) and SDSS]. The full QSO sample (including objects previously observed in the SDSS and 2QZ surveys) contains 12702 QSOs. The new 2SLAQ spectroscopic data set also contains 2343 Galactic stars, including 362 white dwarfs, and 2924 narrow emission-line galaxies with a median redshift of z=0.22.
1963. The DiskMass survey. I.
ID:
ivo://CDS.VizieR/J/ApJ/716/198
Title:
The DiskMass survey. I.
Short Name:
J/ApJ/716/198
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a survey of the mass surface density of spiral disks, motivated by outstanding uncertainties in rotation-curve decompositions. Our method exploits integral-field spectroscopy to measure stellar and gas kinematics in nearly face-on galaxies sampled at 515, 660, and 860nm, using the custom-built SparsePak and PPak instruments. A two-tiered sample, selected from the UGC, includes 146 nearly face-on galaxies, with B<14.7 and disk scale lengths between 10 and 20 arcsec, for which we have obtained H{alpha} velocity fields; and a representative 46 galaxy subset for which we have obtained stellar velocities and velocity dispersions. The survey is augmented by 4-70um Spitzer IRAC and MIPS photometry, ground-based UBVRIJHK photometry, and HI aperture-synthesis imaging. We outline the spectroscopic analysis protocol for deriving precise and accurate line-of-sight stellar velocity dispersions. Our key measurement is the dynamical disk-mass surface density. Star formation rates and kinematic and photometric regularity of galaxy disks are also central products of the study.
1964. The distance modulus of the LMC
ID:
ivo://CDS.VizieR/J/A+A/363/L1
Title:
The distance modulus of the LMC
Short Name:
J/A+A/363/L1
Date:
21 Oct 2021
Publisher:
CDS
Description:
We use double-mode RR Lyrae (RRd) stars from the MACHO variable star database of the Large Magellanic Cloud (LMC) to estimate its distance, by utilizing photometric data, linear pulsation and stellar atmosphere models. If we set E_(B-V)_=0.11 and [M/H]=-1.5 for LMC, we get M-m=18.52mag. The fact that the distance moduli obtained in this and in our former studies of cluster RRd and Small Magellanic Cloud beat Cepheids agree so well, implies that the only serious source of error is the zero point of the temperature scale, which should not have larger than +/-0.10mag effect on the distance modulus.
1965. The DRAO polarization survey
ID:
ivo://CDS.VizieR/J/A+A/448/411
Title:
The DRAO polarization survey
Short Name:
J/A+A/448/411
Date:
21 Oct 2021
Publisher:
CDS
Description:
The fits files contain the observed and interpolated data of a survey of linear polarization (Stokes U and Q) at 1.4GHz, obtained with the 25.6-m telescope of the Dominion Radio Astrophysical Observatory in Canada. The angular resolution is 36 arcmin. The data are corrected for ground radiation and tied to absolute determinations of zero levels. Survey observations were carried out by drift scanning the sky between -29{deg} and +90{deg} declination. The fully Nyquist- sampled drift scans were observed in steps of 0.25{deg} to about 2.5{deg} in declination. The rms noise is 12mK in Stokes U and Q.
1966. The Einstein@Home gamma-ray pulsar survey. II.
ID:
ivo://CDS.VizieR/J/ApJ/854/99
Title:
The Einstein@Home gamma-ray pulsar survey. II.
Short Name:
J/ApJ/854/99
Date:
21 Oct 2021
Publisher:
CDS
Description:
We report on the analysis of 13 gamma-ray pulsars discovered in the Einstein@Home blind search survey using Fermi Large Area Telescope (LAT) Pass 8 data. The 13 new gamma-ray pulsars were discovered by searching 118 unassociated LAT sources from the third LAT source catalog (3FGL), selected using the Gaussian Mixture Model machine-learning algorithm on the basis of their gamma-ray emission properties being suggestive of pulsar magnetospheric emission. The new gamma-ray pulsars have pulse profiles and spectral properties similar to those of previously detected young gamma-ray pulsars. Follow-up radio observations have revealed faint radio pulsations from two of the newly discovered pulsars and enabled us to derive upper limits on the radio emission from the others, demonstrating that they are likely radio-quiet gamma-ray pulsars. We also present results from modeling the gamma-ray pulse profiles and radio profiles, if available, using different geometric emission models of pulsars. The high discovery rate of this survey, despite the increasing difficulty of blind pulsar searches in gamma rays, suggests that new systematic surveys such as presented in this article should be continued when new LAT source catalogs become available.
1967. The Einstein Observatory HRI Source List
ID:
ivo://CDS.VizieR/IX/24
Title:
The Einstein Observatory HRI Source List
Short Name:
IX/24
Date:
21 Oct 2021
Publisher:
CDS
Description:
The Einstein Observatory is the second of NASA's three High Energy Astrophysical Observatories, HEAO-2, renamed Einstein after launch, and was the first fully imaging X-ray telescope put into space. It observed in the energy range 0.2-20keV. It was launched on 12 November 1978, and remained in operation until April 1981. The High Resolution Imager (HRI) is one fo the four instruments aboard the Einstein Observatory, operating in the 0.2-3.0keV energy range, with a spatial resolution of a few arcseconds, and a field of view of 25arcmin. Field and source parameters observed with this instrument are given here.
1968. The ELQS in SDSS footprint. II. North Gal. Cap
ID:
ivo://CDS.VizieR/J/ApJ/863/144
Title:
The ELQS in SDSS footprint. II. North Gal. Cap
Short Name:
J/ApJ/863/144
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the North Galactic Cap sample of the Extremely Luminous Quasar Survey (ELQS-N), which targets quasars with M_1450_{<}-27 at 2.8<=z<5 in an area of ~7600deg^2^ of the Sloan Digital Sky Survey (SDSS) footprint with 90{deg}<RA<270{deg}. Based on a near-infrared/infrared JKW2 color cut, the ELQS selection efficiently uses random forest methods to classify quasars and to estimate photometric redshifts; this scheme overcomes some of the difficulties of pure optical quasar selection at z~3. As a result, we retain a completeness of >70% over z~3.0-5.0 at m_i_<~17.5, limited toward fainter magnitudes by the depth of the Two Micron All Sky Survey. The presented quasar catalog consists of a total of 270 objects, of which 39 are newly identified in this work with spectroscopy obtained at the Vatican Advanced Technology Telescope and the MMT 6.5m telescope. In addition to the high completeness, which allowed us to discover new quasars in the already well-surveyed SDSS North Galactic Cap, the efficiency of our selection is relatively high at ~79%. Using 120 objects of this quasar sample we are able to extend the previously measured optical quasar luminosity function (QLF) by one magnitude toward the bright end at 2.8<=z<=4.5. A first analysis of the QLF suggests a relatively steep bright-end slope of {beta}~-4 for this sample. This result contrasts with previous results in the same redshift range, which find a much flatter slope around {beta}~-2.5, but agrees with recent measurements of the bright-end slope at lower and higher redshifts. Our results constrain the bright-end slope at z=2.8-4.5 to {beta}{<}-2.94 with a 99% confidence.
1969. The ELQS in the PS1 footprint (PS-ELQS)
ID:
ivo://CDS.VizieR/J/ApJS/243/5
Title:
The ELQS in the PS1 footprint (PS-ELQS)
Short Name:
J/ApJS/243/5
Date:
08 Mar 2022 13:10:17
Publisher:
CDS
Description:
We present the results of the Extremely Luminous Quasar Survey in the 3{pi} survey of the Panoramic Survey Telescope and Rapid Response System (Pan-STARRS; PS1). This effort applies the successful quasar selection strategy of the Extremely Luminous Survey in the Sloan Digital Sky Survey footprint (~12000deg^2^) to a much larger area (~21486deg^2^). This spectroscopic survey targets the most luminous quasars (M_1450_<=-26.5; m_i_<=18.5) at intermediate redshifts (z>=2.8). Candidates are selected based on a near-infrared JKW2 color cut using WISE AllWISE and 2MASS photometry to mainly reject stellar contaminants. Photometric redshifts (z_reg_) and star-quasar classifications for each candidate are calculated from near-infrared and optical photometry using the supervised machine learning technique random forests. We select 806 quasar candidates at z_reg_>=2.8 from a parent sample of 74318 sources. After exclusion of known sources and rejection of candidates with unreliable photometry, we have taken optical identification spectra for 290 of our 334 good PS-ELQS candidates. We report the discovery of 190 new z>=2.8 quasars and an additional 28 quasars at lower redshifts. A total of 44 good PS-ELQS candidates remain unobserved. Including all known quasars at z>=2.8, our quasar selection method has a selection efficiency of at least 77%. At lower declinations, -30<=DEC<=0, we approximately treble the known population of extremely luminous quasars. We provide the PS-ELQS quasar catalog with a total of 592 luminous quasars (m_i_<=18.5, z>=2.8). This unique sample will not only be able to provide constraints on the volume density and quasar clustering of extremely luminous quasars, but also offers valuable targets for studies of the intergalactic medium.
1970. The ESO DIBs Large Exploration Survey
ID:
ivo://CDS.VizieR/J/A+A/606/A76
Title:
The ESO DIBs Large Exploration Survey
Short Name:
J/A+A/606/A76
Date:
21 Oct 2021
Publisher:
CDS
Description:
The carriers of the diffuse interstellar bands (DIBs) are largely unidentified molecules ubiquitously present in the interstellar medium (ISM). After decades of study, two strong and possibly three weak near-infrared DIBs have recently been attributed to the C^+^_60_ fullerene based on observational and laboratory measurements. There is great promise for the identification of the over 400 other known DIBs, as this result could provide chemical hints towards other possible carriers. In an effort to systematically study the properties of the DIB carriers, we have initiated a new large-scale observational survey: the ESO Diffuse Interstellar Bands Large Exploration Survey (EDIBLES). The main objective is to build on and extend existing DIB surveys to make a major step forward in characterising the physical and chemical conditions for a statistically significant sample of interstellar lines-of-sight, with the goal to reverse-engineer key molecular properties of the DIB carriers. EDIBLES is a filler Large Programme using the Ultraviolet and Visual Echelle Spectrograph at the Very Large Telescope at Paranal, Chile. It is designed to provide an observationally unbiased view of the presence and behaviour of the DIBs towards early-spectral-type stars whose lines-of-sight probe the diffuse-to-translucent ISM. Such a complete dataset will provide a deep census of the atomic and molecular content, physical conditions, chemical abundances and elemental depletion levels for each sightline. Achieving these goals requires a homogeneous set of high-quality data in terms of resolution (R~70000-100000), sensitivity (S/N up to 1000 per resolution element), and spectral coverage (305-1042nm), as well as a large sample size (100+ sightlines). In this first paper the goals, objectives and methodology of the EDIBLES programme are described and an initial assessment of the data is provided.

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