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651. 400d Cluster Survey Weak Lensing Programme II
ID:
ivo://CDS.VizieR/J/A+A/546/A79
Title:
400d Cluster Survey Weak Lensing Programme II
Short Name:
J/A+A/546/A79
Date:
21 Oct 2021
Publisher:
CDS
Description:
Evolution in the mass function of galaxy clusters sensitively traces both the expansion history of the Universe and cosmological structure formation. Robust cluster mass determinations are a key ingredient for a reliable measurement of this evolution, especially at high redshift. Weak gravitational lensing is a promising tool for, on average, unbiased mass estimates. This weak lensing project aims at measuring reliable weak lensing masses for a complete X-ray selected sample of 36 high redshift (0.35<z<0.9) clusters. The goal of this paper is to demonstrate the robustness of the methodology against commonly encountered problems, including pure instrumental effects, the presence of bright (8-9mag) stars close to the cluster centre, ground based measurements of high-z (z~0.8) clusters, and the presence of massive unrelated structures along the line-sight.
652. 2D decomposition of CALIFA galaxies
ID:
ivo://CDS.VizieR/J/A+A/598/A32
Title:
2D decomposition of CALIFA galaxies
Short Name:
J/A+A/598/A32
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a two-dimensional multi-component photometric decomposition of 404 galaxies from the Calar Alto Legacy Integral Field Area Data Release 3 (CALIFA-DR3). They represent all possible galaxies with no clear signs of interaction and not strongly inclined in the final CALIFA data release. Galaxies are modelled in the g, r, and i Sloan Digital Sky Survey (SDSS) images including, when appropriate, a nuclear point source, bulge, bar, and an exponential or broken disc component. We use a human-supervised approach to determine the optimal number of structures to be included in the fit. The dataset, including the photometric parameters of the CALIFA sample, is released together with statistical errors and a visual analysis of the quality of each fit. The analysis of the photometric components reveals a clear segregation of the structural composition of galaxies with stellar mass. At high masses (log(M*/M_{sun}_)>11), the galaxy population is dominated by galaxies modelled with a single Sersic or a bulge+disc with a bulge-to-total (B/T) luminosity ratio B/T>0.2. At intermediate masses (9.5<log(M*/M_{sun}_)<11), galaxies described with bulge+disc but B/T<0.2 are preponderant, whereas, at the low mass end (log(M*/M_{\sun}_)<9.5), the prevailing population is constituted by galaxies modelled with either pure discs or nuclear point sources+discs (i.e., no discernible bulge). The analyses of the extended multi-component radial profile result in a volume-corrected distribution of 62%, 28%, and 10% for the so-called Type I (pure exponential), Type II (down-bending), and Type III (up-bending) disc profiles, respectively. These fractions are in discordance with previous findings. We argue that the different methodologies used to detect the breaks are the main cause for these differences.
653. DDO Photoelectric Photometric Catalog
ID:
ivo://CDS.VizieR/II/164
Title:
DDO Photoelectric Photometric Catalog
Short Name:
II/164
Date:
21 Oct 2021
Publisher:
CDS
Description:
This catalogue collects the DDO photometric data published in the astronomical literature until the end of 1988, and contains 8034 DDO measurements, concerning 6139 stars. The DDO 6-filter has the following peak wavelengths and widths: ------------------------ Filter Peak Width [nm] [nm] ------------------------ 35 346.0 38.3 38 381.5 33.0 41 416.6 8.3 42 425.7 7.3 45 451.7 7.6 48 488.6 18.6 51 (*) 513.0 13.4 ------------------------ (*) additional to DDO.
654. DDO Photometry and Radial Velocities at Galactic Poles
ID:
ivo://CDS.VizieR/V/33
Title:
DDO Photometry and Radial Velocities at Galactic Poles
Short Name:
V/33
Date:
21 Oct 2021
Publisher:
CDS
Description:
This catalogue includes the DDO photometry and the radial velocities observed for the study of the kinematics and abundance gradients of G and K stars in the Galactic poles regions.
655. Debris disk candidates detected with AKARI/FIS
ID:
ivo://CDS.VizieR/J/AJ/148/3
Title:
Debris disk candidates detected with AKARI/FIS
Short Name:
J/AJ/148/3
Date:
21 Oct 2021
Publisher:
CDS
Description:
We cross-correlate the Hipparcos main-sequence star catalog with the AKARI/FIS catalog and identify 136 stars (at >90% reliability) with far-infrared detections in at least one band. After rejecting 57 stars classified as young stellar objects, Be stars and other type stars with known dust disks or with potential contaminations, and 4 stars without infrared excess emission, we obtain a sample of 75 candidate stars with debris disks. Stars in our sample cover spectral types from B to K with most being early types. This represents a unique sample of luminous debris disks that derived uniformly from an all-sky survey with a spatial resolution factor of four better than the previous such survey by IRAS. Moreover, by collecting the infrared photometric data from other public archives, almost three-quarters of them have infrared excesses in more than one band, allowing an estimate of the dust temperatures. We fit the blackbody model to the broadband spectral energy distribution of these stars to derive the statistical distribution of the disk parameters. Four B stars with excesses in four or more bands require a double blackbody model, with the high one around 100 or 200K and the low one around 40-50K.
656. DECam phot. of Gaia stars in Price-Whelan 1
ID:
ivo://CDS.VizieR/J/ApJ/887/19
Title:
DECam phot. of Gaia stars in Price-Whelan 1
Short Name:
J/ApJ/887/19
Date:
21 Oct 2021
Publisher:
CDS
Description:
We report the discovery of a young ({tau}~117Myr), low-mass (M~1200M_{sun}_), metal-poor ([Fe/H]~-1.14) stellar association at a heliocentric distance D~28.7kpc, placing it far into the Milky Way (MW) halo. At its present Galactocentric position (R,z)~(23,15)kpc, the association is (on the sky) near the leading arm of the gas stream emanating from the Magellanic Cloud system, but is located ~60{deg} from the Large Magellanic Cloud center on the other side of the MW disk. If the cluster is colocated with HI gas in the stream, we directly measure the distance to the leading arm of the Magellanic stream. The measured distance is inconsistent with Magellanic stream model predictions that do not account for ram pressure and gas interaction with the MW disk. The estimated age of the cluster is consistent with the time of last passage of the leading arm gas through the Galactic midplane; we therefore speculate that this star formation event was triggered by its last disk midplane passage. Most details of this idea remain a puzzle: the Magellanic stream has low column density, the MW disk at large radii has low gas density, and the relative velocity of the leading arm and MW gas is large. However it formed, the discovery of a young stellar cluster in the MW halo presents an interesting opportunity for study. This cluster was discovered with Gaia astrometry and photometry alone, but follow-up DECam photometry was crucial for measuring its properties.
657. DECam r and i magnitudes in the Fornax 6 cluster
ID:
ivo://CDS.VizieR/J/ApJ/875/L13
Title:
DECam r and i magnitudes in the Fornax 6 cluster
Short Name:
J/ApJ/875/L13
Date:
21 Oct 2021
Publisher:
CDS
Description:
Since first noticed by Shapley in 1939, a faint object coincident with the Fornax dwarf spheroidal has long been discussed as a possible sixth globular cluster (GC) system. However, debate has continued over whether this overdensity is a statistical artifact or a blended galaxy group. In this Letter we demonstrate, using deep DECam imaging data, that this object is well resolved into stars and is a bona fide star cluster. The stellar overdensity of this cluster is statistically significant at the level of ~6-6.7{sigma} in several different photometric catalogs including Gaia. Therefore, it is highly unlikely to be caused by random fluctuation. We show that Fornax 6 is a star cluster with a peculiarly low surface brightness and irregular shape, which may indicate a strong tidal influence from its host galaxy. The Hess diagram of Fornax 6 is largely consistent with that of Fornax field stars, but it appears to be slightly bluer. However, it is still likely more metal-rich than most of the GCs in the system. Faint clusters like Fornax 6 that orbit and potentially get disrupted in the centers of dwarf galaxies can prove crucial for constraining the dark matter distribution in Milky Way satellites.
658. DECam Survey of Scorpius Centaurus
ID:
ivo://CDS.VizieR/J/MNRAS/484/5049
Title:
DECam Survey of Scorpius Centaurus
Short Name:
J/MNRAS/484/5049
Date:
21 Oct 2021
Publisher:
CDS
Description:
Using images taken with the Dark Energy Camera (DECam), the first extensive survey of low mass and substellar objects is made in the ~15-20Myr Upper Centaurus Lupus (UCL) and Lower Centaurus Crux (LCC) subgroups of the Scorpius-Centaurus OB Association (Sco-Cen). Due to the size of our data set (>2Tb), we developed an extensive open source set of python libraries to reduce our images, including astrometry, coaddition, and PSF photometry. Our survey consists of 29x3deg^2^ fields in the UCL and LCC subgroups of Sco-Cen and the creation of a catalogue with over 11 million point sources. We create a prioritized list of UCL and LCC candidate members, with 118 best and another 348 good candidates. We show that the luminosity and mass functions of our low mass and substellar candidates are consistent with measurements for the younger Upper Scorpius subgroup and estimates of a universal IMF, with spectral types ranging from M1 down to L1.
659. Deep all-sky census of the Hyades
ID:
ivo://CDS.VizieR/J/A+A/531/A92
Title:
Deep all-sky census of the Hyades
Short Name:
J/A+A/531/A92
Date:
21 Oct 2021
Publisher:
CDS
Description:
On the basis of the PPMXL catalogue we perform an all-sky census of the Hyades down to masses of about 0.2M_{sun}_ in a region up to 30pc from the cluster centre. We use the proper motions from PPMXL in the convergent point method to determine probable kinematic members. From 2MASS photometry and CMC14 r'-band photometry, we derive empirical colour-absolute magnitude diagrams and, finally, determine photometric membership for all kinematic candidates. This is the first deep (r'<17) all-sky survey of the Hyades allowing a full three-dimensional analysis of the cluster. The survey is complete down to at least M_{K_s_}_=7.3 or 0.25M_{sun}_. We find 724 stellar systems co-moving with the bulk Hyades space velocity, which represent a total mass of 435M_{sun}_. The tidal radius is about 9pc, and 275M_{sun}_ (364 systems) are gravitationally bound. This is the cluster proper. Its mass density profile is perfectly fitted by a Plummer model with a central density of 2.21M_{sun}_/pc^3^ and a core radius of r_co_=3.10pc, while the half-mass radius is r_h_=4.1pc. There are another 100M_{sun}_ in a volume between one and two tidal radii (halo), and another 60M_{sun}_ up to a distance of 30pc from the centre. Strong mass segregation is inherent in the cluster. The present-day luminosity and mass functions are noticeably different in various parts of the cluster (core, corona, halo, and co-movers). They are strongly evolved compared to presently favoured initial mass functions. The analysis of the velocity dispersion of the cluster shows that about 20% of its members must be binaries. As a by-product, we find that presently available theoretical isochrones are not able to adequately describe the near-infrared colour-absolute magnitude relation for those cluster stars that are less massive than about 0.6M_{sun}_.
660. Deep ATLAS radio observations of CDFS
ID:
ivo://CDS.VizieR/J/AJ/132/2409
Title:
Deep ATLAS radio observations of CDFS
Short Name:
J/AJ/132/2409
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the first results from the Australia Telescope Large Area Survey, which consists of deep radio observations of a 3.7deg^2^ field surrounding the Chandra Deep Field-South, largely coincident with the infrared Spitzer Wide-Area Infrared Extragalactic (SWIRE) Survey. We also list cross-identifications to infrared and optical photometry data from SWIRE, and ground-based optical spectroscopy. A total of 784 radio components are identified, corresponding to 726 distinct radio sources, nearly all of which are identified with SWIRE sources. Of the radio sources with measured redshifts, most lie in the redshift range 0.5-2 and include both star-forming galaxies and active galactic nuclei. We identify a rare population of infrared-faint radio sources that are bright at radio wavelengths but are not seen in the available optical, infrared, or X-ray data. Such rare classes of sources can only be discovered in wide, deep surveys such as this.