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3741. The CSP (DR3): photometry of low-z SNe Ia
ID:
ivo://CDS.VizieR/J/AJ/154/211
Title:
The CSP (DR3): photometry of low-z SNe Ia
Short Name:
J/AJ/154/211
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present final natural-system optical (ugriBV) and near-infrared (YJH) photometry of 134 supernovae (SNe) with probable white dwarf progenitors that were observed in 2004-2009 as part of the first stage of the Carnegie Supernova Project (CSP-I). The sample consists of 123 Type Ia SNe, 5 Type Iax SNe, 2 super-Chandrasekhar SN candidates, 2 Type Ia SNe interacting with circumstellar matter, and 2 SN 2006bt-like events. The redshifts of the objects range from z=0.0037 to 0.0835; the median redshift is 0.0241. For 120 (90%) of these SNe, near-infrared photometry was obtained. Average optical extinction coefficients and color terms are derived and demonstrated to be stable during the five CSP-I observing campaigns. Measurements of the CSP-I near-infrared bandpasses are also described, and near-infrared color terms are estimated through synthetic photometry of stellar atmosphere models. Optical and near-infrared magnitudes of local sequences of tertiary standard stars for each supernova are given, and a new calibration of Y-band magnitudes of the Persson et al. (1998AJ....116.2475P) standards in the CSP-I natural system is presented.
3742. The CSP (DR2): photometry of SNe Ia
ID:
ivo://CDS.VizieR/J/AJ/142/156
Title:
The CSP (DR2): photometry of SNe Ia
Short Name:
J/AJ/142/156
Date:
21 Oct 2021
Publisher:
CDS
Description:
The Carnegie Supernova Project (CSP) was a five-year observational survey conducted at Las Campanas Observatory that obtained, among other things, high-quality light curves of ~100 low-redshift Type Ia supernovae (SNe Ia). Presented here is the second data release of nearby SN Ia photometry consisting of 50 objects, with a subset of 45 having near-infrared follow-up observations. Thirty-three objects have optical pre-maximum coverage with a subset of 15 beginning at least five days before maximum light. In the near-infrared, 27 objects have coverage beginning before the epoch of B-band maximum, with a subset of 13 beginning at least five days before maximum. In addition, we present results of a photometric calibration program to measure the CSP optical (uBgVri) bandpasses with an accuracy of ~1%. Finally, we report the discovery of a second SN Ia, SN 2006ot, similar in its characteristics to the peculiar SN 2006bt.
3743. The Dark Energy Survey (DES): Data Release 1
ID:
ivo://CDS.VizieR/II/357
Title:
The Dark Energy Survey (DES): Data Release 1
Short Name:
II/357
Date:
21 Oct 2021
Publisher:
CDS
Description:
We describe the first public data release of the Dark Energy Survey, DES DR1, consisting of reduced single-epoch images, co-added images, co-added source catalogs, and associated products and services assembled over the first 3yr of DES science operations. DES DR1 is based on optical/near-infrared imaging from 345 distinct nights (2013 August to 2016 February) by the Dark Energy Camera (DECam) mounted on the 4m Blanco telescope at the Cerro Tololo Inter-American Observatory in Chile. We release data from the DES wide-area survey covering ~5000deg^2^ of the southern Galactic cap in five broad photometric bands, grizY. DES DR1 has a median delivered point-spread function of g=1.12, r=0.96, i=0.88, z=0.84, and Y=0.90" FWHM, a photometric precision of <1% in all bands, and an astrometric precision of 151mas. The median co-added catalog depth for a 1.95" diameter aperture at signal-to-noise ratio (S/N)=10 is g=24.33, r=24.08, i=23.44, z=22.69, and Y=21.44mag. DES DR1 includes nearly 400 million distinct astronomical objects detected in ~10000 co-add tiles of size 0.534deg^2^ produced from ~39000 individual exposures. Benchmark galaxy and stellar samples contain ~310 million and ~80 million objects, respectively, following a basic object quality selection. DES DR1 constitutes the largest photometric data set to date at the achieved depth and photometric precision.
3744. The Dark Energy Survey (DES): Data Release 2
ID:
ivo://CDS.VizieR/II/371
Title:
The Dark Energy Survey (DES): Data Release 2
Short Name:
II/371
Date:
31 Jan 2022
Publisher:
CDS
Description:
We present the second public data release of the Dark Energy Survey, DES DR2, based on optical/near-infrared imaging by the Dark Energy Camera mounted on the 4m Blanco telescope at Cerro Tololo Inter-American Observatory in Chile. DES DR2 consists of reduced single-epoch and coadded images, a source catalog derived from coadded images, and associated data products assembled from 6yr of DES science operations. This release includes data from the DES wide-area survey covering ~5000deg^2^ of the southern Galactic cap in five broad photometric bands, grizY. DES DR2 has a median delivered point-spread function FWHM of g=1.11", r=0.95", i=0.88", z=0.83", and Y=0.90", photometric uniformity with a standard deviation of <3mmag with respect to Gaia DR2 G band, a photometric accuracy of ~11mmag, and a median internal astrometric precision of ~27mas. The median coadded catalog depth for a 1farcs95 diameter aperture at signal-to-noise ratio =10 is g=24.7, r=24.4, i=23.8, z=23.1, and Y=21.7mag. DES DR2 includes ~691 million distinct astronomical objects detected in 10169 coadded image tiles of size 0.534deg^2^ produced from 76217 single-epoch images. After a basic quality selection, benchmark galaxy and stellar samples contain 543 million and 145 million objects, respectively.
3745. The DEBCat detached eclipsing binary catalogue
ID:
ivo://CDS.VizieR/V/152
Title:
The DEBCat detached eclipsing binary catalogue
Short Name:
V/152
Date:
21 Oct 2021
Publisher:
CDS
Description:
Detached eclipsing binary star systems are our primary source of measured physical properties of normal stars. I introduce DEBCat: a catalog of detached eclipsing binaries with mass and radius measurements to the 2% precision necessary to put useful constraints on theoretical models of stellar evolution. The catalog was begun in 2006, as an update of the compilation by Andersen (1991A&ARv...3...91A). It now contains over 195 systems (2017/10/10), and new results are added on appearance in the refereed literature.
3746. The DEEP2-DR1 Photometric Catalog
ID:
ivo://CDS.VizieR/II/301
Title:
The DEEP2-DR1 Photometric Catalog
Short Name:
II/301
Date:
21 Oct 2021
Publisher:
CDS
Description:
The Deep Extragalactic Evolutionary Probe (DEEP) is a multi-year program which uses the twin 10m Keck Telescopes and the Hubble Space Telescope (HST) to conduct a truly large-scale survey of distant, faint, field galaxies. The broad scientific goals include: the formation and evolution of galaxies, the origin of large-scale structure, the nature of the dark matter, and the geometry of the Universe. This project is led by the Lick Observatory at University of California (UC) Santa Cruz, in collaboration with UC Berkeley, University of Hawaii (UH) Manoa, Johns Hopkins University, University of Chicago and California Institute of Technology. The photometric data were taken with the CFH12K camera on the 3.6-meter Canada-France-Hawai'i Telescope. Each DEEP2 field is covered by multiple CFHT/CFH12K pointings with each pointing numbered within its respective
3747. 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.
3748. The doubly lensed quasar SDSS J1001+5027
ID:
ivo://CDS.VizieR/J/A+A/557/A44
Title:
The doubly lensed quasar SDSS J1001+5027
Short Name:
J/A+A/557/A44
Date:
21 Oct 2021
Publisher:
CDS
Description:
This paper presents optical R-band light curves and the time delay of the doubly imaged gravitationally lensed quasar SDSS J1001+5027 at a redshift of 1.838. We have observed this target for more than six years, between March 2005 and July 2011, using the 1.2-m Mercator Telescope, the 1.5-m telescope of the Maidanak Observatory and the 2-m Himalayan Chandra Telescope. Our resulting light curves are composed of 443 independent epochs, and show strong intrinsic quasar variability, with an amplitude of the order of 0.2 magnitudes. From this data, we measure the time delay using five different methods, all relying on distinct approaches. One of these techniques is a new development presented in this paper. All our time-delay measurements are perfectly compatible. By combining them, we conclude that image A is leading B by 119.3+/-3.3 days (1{sigma}, 2.8%), including systematic errors. It has been shown recently that such accurate time-delay measurements offer a highly complementary probe of dark energy and spatial curvature, as they independently constrain the Hubble constant. The next mandatory step towards using SDSS J1001+5027 in this context will be the measurement of the redshift of the lensing galaxy, in combination with deep HST imaging.
3749. The edge of the young Galactic disk
ID:
ivo://CDS.VizieR/J/ApJ/718/683
Title:
The edge of the young Galactic disk
Short Name:
J/ApJ/718/683
Date:
21 Oct 2021
Publisher:
CDS
Description:
In this work, we report and discuss the detection of two distant diffuse stellar groups in the third Galactic quadrant. They are composed of young stars, with spectral types ranging from late O to late B, and lie at galactocentric distances between 15 and 20kpc. These groups are located in the area of two cataloged open clusters (VdB-Hagen 04 and Ruprecht 30), projected toward the Vela-Puppis constellations, and within the core of the Canis Major overdensity. Their reddening and distances have been estimated by analyzing their color-color and color-magnitude diagrams, derived from deep UBV photometry. The existence of young star aggregates at such extreme distances from the Galactic center challenges the commonly accepted scenario in which the Galactic disk has a sharp cutoff at about 14kpc from the Galactic center and indicates that it extends to much greater distances (as also supported by the recent detection of CO molecular complexes well beyond this distance). While the groups we find in the area of Ruprecht 30 are compatible with the Orion and Norma-Cygnus spiral arms, respectively, the distant group we identify in the region of VdB-Hagen 04 lies in the external regions of the Norma-Cygnus arm, at a galactocentric distance (~20kpc) where no young stars have been detected so far in the optical.
3750. The ELM survey. I. Low-mass white dwarfs
ID:
ivo://CDS.VizieR/J/ApJ/723/1072
Title:
The ELM survey. I. Low-mass white dwarfs
Short Name:
J/ApJ/723/1072
Date:
21 Oct 2021
Publisher:
CDS
Description:
We analyze radial velocity observations of the 12 extremely low-mass (ELM), with <=0.25M_{sun}_, white dwarfs (WDs) in the MMT Hypervelocity Star Survey. Eleven of the twelve WDs are binaries with orbital periods shorter than 14hr; the one non-variable WD is possibly a pole-on system among our non-kinematically selected targets. Our sample is unique: it is complete in a well-defined range of apparent magnitude and color. The orbital mass functions imply that the unseen companions are most likely other WDs, although neutron star companions cannot be excluded. Six of the eleven systems with orbital solutions will merge within a Hubble time due to the loss of angular momentum through gravitational wave radiation. The quickest merger is J0923+3028, a g=15.7 ELM WD binary with a 1.08hr orbital period and a <=130Myr merger time. The chance of a supernova Ia event among our ELM WDs is only 1%-7%, however. Three binary systems (J0755+4906, J1233+1602, and J2119-0018) have extreme mass ratios and will most likely form stable mass-transfer AM CVn systems. Two of these objects, SDSS J1233+1602 and J2119-0018, are the lowest surface gravity WDs ever found; both show CaII absorption likely from accretion of circumbinary material. We predict that at least one of our WDs is an eclipsing detached double WD system, important for constraining helium core WD models.