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921. GALAH survey. FGK binary stars
ID:
ivo://CDS.VizieR/J/A+A/638/A145
Title:
GALAH survey. FGK binary stars
Short Name:
J/A+A/638/A145
Date:
21 Oct 2021
Publisher:
CDS
Description:
Binary stellar systems form a large fraction of the Galaxy's stars. They are useful as laboratories for studying the physical processes taking place within stars, and must be correctly taken into account when observations of stars are used to study the structure and evolution of the Galaxy. We present a sample of 12760 well-characterised double-lined spectroscopic binaries that are appropriate for statistical studies of the binary populations. They were detected as SB2s using a t-distributed stochastic neighbour embedding (t-SNE) classification and a cross-correlation analysis of GALAH spectra. This sample consists mostly of dwarfs, with a significant fraction of evolved stars and several dozen members of the giant branch. To compute parameters of the primary and secondary star (Teff[1,2], logg[1,2], [Fe/H], Vr[1,2], vmic[1,2], vbroad[1,2], R[1,2], and E(B-V)), we used a Bayesian approach that includes a parallax prior from Gaia DR2, spectra from GALAH, and apparent magnitudes from APASS, Gaia DR2, 2MASS, and WISE. The derived stellar properties and their distributions show trends that are expected for a population of close binaries (a<10AU) with mass ratios 0.5<=q<=1. The derived metallicity of these binary stars is statistically lower than that of single dwarf stars from the same magnitude-limited sample.
922. Galaxies behind Southern Milky Way
ID:
ivo://CDS.VizieR/J/A+AS/141/123
Title:
Galaxies behind Southern Milky Way
Short Name:
J/A+AS/141/123
Date:
21 Oct 2021
Publisher:
CDS
Description:
A deep optical galaxy search in the southern Milky Way - aimed at reducing the width of the Zone of Avoidance - revealed 3279 galaxy candidates on the IIIaJ film copies of the ESO/SRC survey above the diameter limit of D greater than approximately 0.2 arcmin. Only 112 (3.4%) were previously catalogued. The surveyed region (266<l<296 and -10<b<+8) lies in the extension of the Hydra and Antlia clusters. Optical properties of the unveiled galaxies such as positions, diameters, magnitudes, morphological types are given in Table 1. Cross-identifications with the IRAS PSC (Cat. <II/125>) are given in Table 2.
923. Galaxies behind Southern Milky Way. II.
ID:
ivo://CDS.VizieR/J/A+A/380/441
Title:
Galaxies behind Southern Milky Way. II.
Short Name:
J/A+A/380/441
Date:
21 Oct 2021
Publisher:
CDS
Description:
In this second paper of the catalogue series of galaxies behind the southern Milky Way, we report on the deep optical galaxy search in the Crux region (289{deg}<~l<~318{deg} and -10{deg}<~b<~10{deg}) and the Great Attractor region (316{deg}<~l<~338{deg} and -10{deg}<~b<~10{deg}). The galaxy catalogues are presented, a brief description of the galaxy search given, as well as a discussion on the distribution and characteristics of the uncovered galaxies. A total of 8183 galaxies with major diameters D>~0.2 arcmin were identified in this ~850 square degree area: 3759 galaxies in the Crux region and 4423 galaxies in the Great Attractor region. Of the 8183 galaxies, 229 (2.8%) were catalogued before in the optical (3 in radio) and 251 galaxies have a reliable (159), or likely (92) cross-identification in the IRAS Point Source Catalogue (3.1%). A number of prominent overdensities and filaments of galaxies are identified. They are not correlated with the Galactic foreground extinction and hence indicative of extragalactic large-scale structures. Redshifts obtained at the South African Astronomical Observatory (SAAO) for 518 of the newly catalogued galaxies in the Crux and Great Attractor regions (Fairall et al., 1998, Cat. <J/A+AS/127/463>; Woudt et al., 1999, Cat. <J/A+A/352/39>) confirm distinct voids and clusters in the area here surveyed. With this optical galaxy search, we have reduced the width of the optical `Zone of Avoidance' for galaxies with extinction-corrected diameters larger than 1.3' from extinction levels A_B>~1.0mag to A_B>~3.0mag: the remaining optical Zone of Avoidance is now limited by |b|<~3{deg} (see Fig. 16).
924. galaxies 2D phot. decompositions in SDSS-DR7
ID:
ivo://CDS.VizieR/J/MNRAS/446/3943
Title:
galaxies 2D phot. decompositions in SDSS-DR7
Short Name:
J/MNRAS/446/3943
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a catalogue of 2D, point spread function-corrected de Vacouleurs, Sersic, de Vacouleurs+Exponential, and Sersic+Exponential fits of ~7x10^5^ spectroscopically selected galaxies drawn from the Sloan Digital Sky Survey (SDSS) Data Release 7. Fits are performed for the SDSS r band utilizing the fitting routine galfit and analysis pipeline pymorph. We compare these fits to prior catalogues. Fits are analysed using a physically motivated flagging system. The flags suggest that more than 90 percent of two-component fits can be used for analysis. We show that the fits follow the expected behaviour for early and late galaxy types. The catalogues provide a robust set of structural and photometric parameters for future galaxy studies. We show that some biases remain in the measurements, e.g. the presence of bars significantly affect the bulge measurements although the bulge ellipticity may be used to separate barred and non-barred galaxies, and about 15 percent of bulges of two-component fits are also affected by resolution. The catalogues are available in electronic format. We also provide an interface for generating postage stamp images of the 2D model and residual as well as the 1D profile. These images can be generated for a user-uploaded list of galaxies on demand.
925. Galaxies in Lynx-Cancer void
ID:
ivo://CDS.VizieR/J/other/AstBu/69.247
Title:
Galaxies in Lynx-Cancer void
Short Name:
J/other/AstBu/69
Date:
21 Oct 2021
Publisher:
CDS
Description:
In this work we present the results of photometrical study of 85 objects from the updated sample of galaxies residing in the nearby Lynx-Cancer void. The images in filters u,g,r,i from the Sloan Digital Sky Survey database are used for photometry. The following model-independent parameters are obtained: integrated magnitudes and colours, effective radii and the respective surface brightnesses, optical and Holmberg radii. On results of the radial surface brightness profile analysis, their central values and scalelengths of model discs are derived. The colours of the outer parts of void galaxies are examined and compared to those of the model evolutionary tracks of the PEGASE2 package. This allowed to obtain estimates of the time since the epoch of star formation T_SF_. Among the latter group, the low-luminosity objects with M_B_>-13.2 dominate. The derived integrated absolute magnitudes and colours are used for galaxy stellar mass estimates. All available data on integrated galaxy HI fluxes are used to derive their parameter M(HI)/L_B_ and to estimate their gas mass-fraction. The small ~10% subgroup of the most gas-rich galaxies, with M(HI)/L_B_>2.5, shows gas mass-fractions reaching (94-99)%. Many of these objects also show atypically blue colours of their outer parts. To check possible statistical differences of void galaxy properties and galaxy samples formed with more general criteria, we compared the void sample galaxy parameters with those of 195 galaxies from the Equatorial Survey (ES), formed as a part of the blind HI survey HIPASS. In the common luminosity range (-18.5<M_g_<-13.5) the compared samples show similarity. The lowest luminosity void galaxies differ from the main ES sample. However, there are also ~7% faint so called 'inchoate' galaxies among ES sample with the elevated parameter M(HI)/L_B_, majority of which are situated far from massive neighbours and are probably the analogs of void galaxies.
926. Galaxies inside 120 arcsec of HE 0435-1223
ID:
ivo://CDS.VizieR/J/MNRAS/467/4220
Title:
Galaxies inside 120 arcsec of HE 0435-1223
Short Name:
J/MNRAS/467/4220
Date:
21 Oct 2021
Publisher:
CDS
Description:
Based on spectroscopy and multiband wide-field observations of the gravitationally lensed quasar HE 0435-1223, we determine the probability distribution function of the external convergence {kappa}_ext_ for this system. We measure the under/overdensity of the line of sight towards the lens system and compare it to the average line of sight throughout the Universe, determined by using the CFHTLenS (The Canada France Hawaii Lensing Survey) as a control field. Aiming to constrain {kappa}_ext_ as tightly as possible, we determine under/overdensities using various combinations of relevant informative weighting schemes for the galaxy counts, such as projected distance to the lens, redshift and stellar mass. We then convert the measured under/overdensities into a {kappa}_ext_ distribution, using ray-tracing through the Millennium Simulation. We explore several limiting magnitudes and apertures, and account for systematic and statistical uncertainties relevant to the quality of the observational data, which we further test through simulations. Our most robust estimate of {kappa}_ext_ has a median value {kappa}^med^_ext_=0.004 and a standard deviation {sigma}_{kappa}_=0.025. The measured {sigma}_{kappa}_ corresponds to 2.5 per cent relative uncertainty on the time delay distance, and hence the Hubble constant H_0_ inferred from this system. The median {kappa}^med^_ext_ value varies by ~0.005 with the adopted aperture radius, limiting magnitude and weighting scheme, as long as the latter incorporates galaxy number counts, the projected distance to the main lens and a prior on the external shear obtained from mass modelling. This corresponds to just ~0.5 per cent systematic impact on H_0_. The availability of a well-constrained {kappa}_ext_ makes HE 0435-1223 a valuable system for measuring cosmological parameters using strong gravitational lens time delays.
927. Galaxies in the Perseus cluster field
ID:
ivo://CDS.VizieR/J/A+A/640/A30
Title:
Galaxies in the Perseus cluster field
Short Name:
J/A+A/640/A30
Date:
21 Oct 2021
Publisher:
CDS
Description:
We investigate the galaxies brighter than B~20 in the field of the Perseus cluster. The galaxies were selected on Schmidt CCD images in B and Halpha in combination with SDSS images. The survey field roughly covers the virial radius of the cluster. The galaxy sample is used for analysing cluster properties, such as radial profiles, indications of sub-structure, virial mass, and viral radius and is applied for a study of the cluster galaxy population with an emphasis on morphological types and peculiarities, star formation rates and active galactic nuclei.
928. Galaxies in the Tycho-2 catalogue
ID:
ivo://CDS.VizieR/J/A+A/413/771
Title:
Galaxies in the Tycho-2 catalogue
Short Name:
J/A+A/413/771
Date:
21 Oct 2021
Publisher:
CDS
Description:
The accuracy of the link of the proper motion system of astrometric satellite missions like AMEX and GAIA is discussed. Monte-Carlo methods were used to simulate catalogues of positions and proper motions of quasars and galaxies to test the link. The main conclusion is, that future satellite missions like GAIA may be "self-calibrated" by their measurements of QSOs, while additional measurements from radio stars or HST-data are needed to calibrate the less deep reaching astrometric satellite missions of AMEX type.
929. Galaxies in X-ray clusters with DES. I. Stellar mass
ID:
ivo://CDS.VizieR/J/ApJ/816/98
Title:
Galaxies in X-ray clusters with DES. I. Stellar mass
Short Name:
J/ApJ/816/98
Date:
21 Oct 2021
Publisher:
CDS
Description:
Using the science verification data of the Dark Energy Survey for a new sample of 106 X-ray selected clusters and groups, we study the stellar mass growth of bright central galaxies (BCGs) since redshift z~1.2. Compared with the expectation in a semi-analytical model applied to the Millennium Simulation, the observed BCGs become under-massive/under-luminous with decreasing redshift. We incorporate the uncertainties associated with cluster mass, redshift, and BCG stellar mass measurements into an analysis of a redshift-dependent BCG-cluster mass relation, m_*_{propto}(M_200_/1.5x10^14^M_{sun}_)^0.24+/-0.08^(1+z)^-0.19+/-0.34, and compare the observed relation to the model prediction. We estimate the average growth rate since z=1.0 for BCGs hosted by clusters of M_200,z_=10^13.8^M_{sun}_; at z=1.0: m_*,BCG_ appears to have grown by 0.13+/-0.11dex, in tension at the ~2.5{sigma} significance level with the 0.40 dex growth rate expected from the semi-analytic model. We show that the build-up of extended intracluster light after z=1.0 may alleviate this tension in BCG growth rates.
930. Galaxies in X-ray groups. I. COSMOS memberships
ID:
ivo://CDS.VizieR/J/ApJ/742/125
Title:
Galaxies in X-ray groups. I. COSMOS memberships
Short Name:
J/ApJ/742/125
Date:
21 Oct 2021
Publisher:
CDS
Description:
Understanding the mechanisms that lead dense environments to host galaxies with redder colors, more spheroidal morphologies, and lower star formation rates than field populations remains an important problem. As most candidate processes ultimately depend on host halo mass, accurate characterizations of the local environment, ideally tied to halo mass estimates and spanning a range in halo mass and redshift, are needed. In this work, we present and test a rigorous, probabilistic method for assigning galaxies to groups based on precise photometric redshifts and X-ray-selected groups drawn from the COSMOS field. The groups have masses in the range 10^13^<~M_200c_/M_{sun}_<~10^14^ and span redshifts 0<z<1. We characterize our selection algorithm via tests on spectroscopic subsamples, including new data obtained at the Very Large Telescope, and by applying our method to detailed mock catalogs. We find that our group member galaxy sample has a purity of 84% and completeness of 92% within 0.5R_200c_. We measure the impact of uncertainties in redshifts and group centering on the quality of the member selection with simulations based on current data as well as future imaging and spectroscopic surveys. As a first application of our new group member catalog which will be made publicly available, we show that member galaxies exhibit a higher quenched fraction compared to the field at fixed stellar mass out to z~1, indicating a significant relationship between star formation and environment at group scales. We also address the suggestion that dusty star-forming galaxies in such groups may impact the high-l power spectrum of the cosmic microwave background and find that such a population cannot explain the low power seen in recent Sunyaev-Zel'dovich measurements.