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671. S4G disk galaxies stellar mass distribution
ID:
ivo://CDS.VizieR/J/A+A/596/A84
Title:
S4G disk galaxies stellar mass distribution
Short Name:
J/A+A/596/A84
Date:
21 Oct 2021
Publisher:
CDS
Description:
Models of galaxy formation in a cosmological framework require observational constraints to be tested against, such as the average stellar density profiles (and their dispersion) as a function of fundamental galaxy properties (e.g. the total stellar mass). Simulation models predict that the torques produced by stellar bars efficiently redistribute the stellar and gaseous material inside the disk, pushing it outwards or inwards depending on whether it is beyond or inside the bar corotation resonance radius, respectively. Bars themselves are expected to evolve, getting longer and narrower as they trap particles from the disk and slow down their rotation speed. We use 3.6um photometry from the Spitzer Survey of Stellar Structure in Galaxies (S4G) to trace the stellar distribution in nearby disk galaxies (z~~0) with total stellar masses 10^8.5^<=M*/M_{sun}_<=10^11^ and mid IR Hubble types -3<=T<=10. We characterize the stellar density profiles ({SIGMA}*), the stellar contribution to the rotation curves (V3.6um) and the m=2 Fourier amplitudes (A2) as a function of M* and T. We also describe the typical shapes and strengths of stellar bars in the S4G sample and link their properties to the total stellar mass and morphology of their host galaxy. For 1154 S4G galaxies with disk inclinations lower than 65{deg}, we perform a Fourier decomposition and rescale their images to a common frame determined by the size in physical units, by their disk scalelength, and for 748 barred galaxies by both the length and orientation of their bars. We stack the resized density profiles and images to obtain statistically representative average stellar disks and bars in bins of M* and T. Based on the radial force profiles of individual galaxies we calculate the mean stellar contribution to the circular velocity. We also calculate average A2 profiles, where the radius is normalized to R25.5. Furthermore, we infer the gravitational potentials from the synthetic bars to obtain the tangential-to-radial force ratio (QT) and A2 profiles in the different bins. We also apply ellipse fitting to quantitatively characterize the shape of the bar stacks. For M*>=10^9^M_{sun}_, we find a significant difference in the stellar density profiles of barred and non-barred systems: (i) disks in barred galaxies show larger scalelengths (hR) and fainter extrapolated central surface brightnesses ({SIGMA}0), (ii) the mean surface brightness profiles ({SIGMA}*) of barred and non-barred galaxies intersect each other slightly beyond the mean bar length, most likely at the bar corotation, and (iii) the central mass concentration of barred galaxies is larger (by almost a factor 2 when T<=5) than in their non-barred counterparts. The averaged {SIGMA}* profiles follow an exponential slope down to at least ~10M_{sun}_/pc^2^, which is the typical depth beyond which the sample coverage in the radial direction starts to drop. Central mass concentrations in massive systems (>=10^10^M_{sun}_) are substantially larger than in fainter galaxies, and their prominence scales with T. This segregation also manifests in the inner slope of the mean stellar component of the circular velocity: lenticular (S0) galaxies present the most sharply rising V3.6um . Based on the analysis of bar stacks, we show that early- and intermediate-type spirals (0<=T<5) have intrinsically narrower bars compared to later types and S0s, whose bars are oval-shaped. We show a clear agreement between galaxy family and quantitative estimates of bar strength. In early- and intermediate-type spirals, A2 is larger within and beyond the typical bar region among barred galaxies, compared to the non-barred subsample. Strongly barred systems also tend to have larger A2 amplitudes at all radii than their weakly barred counterparts. Using near-IR wavelengths (S4G 3.6um), we provide observational constraints for galaxy formation models to be checked against. In particular, we calculate the mean stellar density profiles, and the disk(+bulge) component of the rotation curve (and their dispersion) in bins of M* and T. We find evidence for bar-induced secular evolution of disk galaxies, in terms of disk spreading and enhanced central mass concentration. We also obtain average bars (2-D), and we show that bars hosted by early-type galaxies are more centrally concentrated and have larger density amplitudes than their late-type counterparts.
672. S4G galaxies disk/bar decomposition
ID:
ivo://CDS.VizieR/J/MNRAS/478/5689
Title:
S4G galaxies disk/bar decomposition
Short Name:
J/MNRAS/478/5689
Date:
08 Feb 2022 00:30:06
Publisher:
CDS
Description:
We present photometric models of 532 disc galaxies in 3.6um images from the Spitzer Survey of Stellar Structure in Galaxies (S^4^G) using the non-parametric DISKFIT algorithm. We first test DISKFIT's performance on 400 synthetic S^4^G-like galaxy images. DISKFIT is unreliable in the bulge region, but accurately disentangles exponential discs from Ferrers bars farther out as long as their position angles differ by more than 5{deg}. We then proceed to model the S^4^G galaxies, successfully fitting 489 of them using an automated approach for initializing DISKFIT, optimizing the model and deriving uncertainties using a bootstrap-resampling technique. The resulting component geometries and surface brightness profiles are compared to those derived by Salo et al. using the parametric model GALFIT. We find generally good agreement between the models, but discrepancies between best-fitting values for individual systems are often significant: the choice of algorithm clearly impacts the inferred disc and bar structure. In particular, we find that DISKFIT typically assigns more light to the bar and less light to the disc relative to the Ferrers and exponential profiles derived using GALFIT in the bar region. Given DISKFIT's reliability at disentangling these components in our synthetic images, we conclude that the surface brightness distributions of barred S^4^G galaxies are not well-represented by these functional forms. The results presented here underscore the importance of validating photometric decomposition algorithms before applying them to real data and the utility of DISKFIT's non-parametric approach at measuring the structure of discs and bars in nearby galaxies.
673. SHARDS S0 and E/S0 with anti-truncated disc
ID:
ivo://CDS.VizieR/J/A+A/604/A119
Title:
SHARDS S0 and E/S0 with anti-truncated disc
Short Name:
J/A+A/604/A119
Date:
21 Oct 2021
Publisher:
CDS
Description:
The controversy about the origin of the structure of early-type S0-E/S0 galaxies may be due to the difficulty of comparing surface brightness profiles with different depths, photometric corrections and point spread function (PSF) effects (which are almost always ignored). We aim to quantify the properties of Type-III (anti-truncated) discs in a sample of S0 galaxies at 0.2<z<0.6. In this paper, we present the sample selection and describe in detail the methods to robustly trace the structure in their outskirts and correct for PSF effects. We have selected and classified a sample of 150 quiescent galaxies at 0.2<z<0.6 in the GOODS-N field. We performed a quantitative structural analysis of 44 S0-E/S0 galaxies. We have corrected their surface brightness profiles for PSF distortions and analysed the biases in the structural and photometric parameters when the PSF correction is not applied. Additionally, we have developed Elbow, an automatic statistical method to determine whether a possible break is significant - or not - and its type. We have made this method publicly available. We find 14 anti-truncated S0-E/S0 galaxies in the range 0.2<z<0.6 (~30% of the final sample). This fraction is similar to the those reported in the local Universe. In our sample, ~25% of the Type-III breaks observed in PSF-uncorrected profiles are artifacts, and their profiles turn into a Type I after PSF correction. PSF effects also soften Type-II profiles. We find that the profiles of Type-I S0 and E/S0 galaxies of our sample are compatible with the inner profiles of the Type-III, in contrast with the outer profiles. We have obtained the first robust and reliable sample of 14 anti-truncated S0-E/S0 galaxies beyond the local Universe, in the range 0.2<z<0.6. PSF effects significantly affect the shape of the surface brightness profiles in galaxy discs even in the case of the narrow PSF of HST/ACS images, so future studies on the subject should make an effort to correct them.
674. SHELS galaxies with 0.02<z<0.1
ID:
ivo://CDS.VizieR/J/AJ/143/102
Title:
SHELS galaxies with 0.02<z<0.1
Short Name:
J/AJ/143/102
Date:
21 Oct 2021
Publisher:
CDS
Description:
Smithsonian Hectospec Lensing Survey (SHELS) is a dense redshift survey covering a 4deg^2^ region to a limiting R=20.6. In the construction of the galaxy catalog and in the acquisition of spectroscopic targets, we paid careful attention to the survey completeness for lower surface brightness dwarf galaxies. Thus, although the survey covers a small area, it is a robust basis for computation of the slope of the faint end of the galaxy luminosity function to a limiting M_R_=-13.3+5logh. We calculate the faint-end slope in the R band for the subset of SHELS galaxies with redshifts in the range 0.02<=z<0.1, SHELS_0.1_. This sample contains 532 galaxies with R<20.6 and with a median surface brightness within the half-light radius of SB_50,R_=21.82mag/arcsec^2^. We used this sample to make one of the few direct measurements of the dependence of the faint end of the galaxy luminosity function on surface brightness. For the sample as a whole the faint-end slope, {alpha}=-1.31+/-0.04, is consistent with both the Blanton et al. analysis of the Sloan Digital Sky Survey (2005ApJ...631..208B, 2005AJ....129.2562B) and the Liu et al. analysis of the COSMOS field (2008ApJ...672..198L). This consistency is impressive given the very different approaches of these three surveys. A magnitude-limited sample of 135 galaxies with optical spectroscopic redshifts with mean half-light surface brightness, SB_50,R_>=22.5mag/arcsec^2^ is unique to SHELS_0.1_. The faint-end slope is {alpha}_22.5_=-1.52+/-0.16. SHELS_0.1_ shows that lower surface brightness objects dominate the faint-end slope of the luminosity function in the field, underscoring the importance of surface brightness limits in evaluating measurements of the faint-end slope and its evolution.
675. SIGRID galaxy sample
ID:
ivo://CDS.VizieR/J/AJ/142/83
Title:
SIGRID galaxy sample
Short Name:
J/AJ/142/83
Date:
21 Oct 2021
Publisher:
CDS
Description:
Using an optically unbiased selection process based on the HIPASS neutral hydrogen survey, we have selected a sample of 83 spatially isolated, gas-rich dwarf galaxies in the southern hemisphere with cz between 350 and 1650km/s, and with R-band luminosities and HI masses less than that of the Small Magellanic Cloud. The sample is an important population of dwarf galaxies in the local universe, all with ongoing star formation, and most of which have no existing spectroscopic data. We are measuring the chemical abundances of these galaxies, using the integral-field spectrograph on the Australian National University 2.3m telescope, the Wide-Field Spectrograph. This paper describes our survey criteria and procedures, lists the survey sample, and reports on initial observations.
676. SIM2D parameters of SDSS-DR7 galaxies
ID:
ivo://CDS.VizieR/J/MNRAS/440/843
Title:
SIM2D parameters of SDSS-DR7 galaxies
Short Name:
J/MNRAS/440/843
Date:
21 Oct 2021
Publisher:
CDS
Description:
Using data from the Sloan Digital Sky Survey (SDSS)-DR7, including structural measurements from 2D surface brightness fits with gim2d, we show how the fraction of quiescent galaxies depends on galaxy stellar mass M*, effective radius Re, fraction of r-band light in the bulge, B/T, and their status as a central or satellite galaxy at 0.01<z<0.2. For central galaxies we confirm that the quiescent fraction depends not only on stellar mass, but also on Re. The dependence is particularly strong as a function of M*/Re^{alpha}^, with {alpha}~1.5. This appears to be driven by a simple dependence on B/T over the mass range 9<log(M*/M_{sun}_)<11.5, and is qualitatively similar even if galaxies with B/T>0.3 are excluded. For satellite galaxies, the quiescent fraction is always larger than that of central galaxies, for any combination of M*, Re and B/T. The quenching efficiency is not constant, but reaches a maximum of ~0.7 for galaxies with 9<log(M*/M_{sun}_)<9.5 and Re<1kpc. This is the same region of parameter space in which the satellite fraction itself reaches its maximum value, suggesting that the transformation from an active central galaxy to a quiescent satellite is associated with a reduction in Re due to an increase in dominance of a bulge component.
677. SL2S galaxy-scale sample of lens candidates
ID:
ivo://CDS.VizieR/J/ApJ/785/144
Title:
SL2S galaxy-scale sample of lens candidates
Short Name:
J/ApJ/785/144
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present RINGFINDER, a tool for finding galaxy-scale strong gravitational lenses in multi-band imaging data. By construction, the method is sensitive to configurations involving a massive foreground ETG and a faint, background, blue source. RINGFINDER detects the presence of blue residuals embedded in an otherwise smooth red light distribution by difference imaging in two bands. The method is automated for efficient application to current and future surveys, having originally been designed for the 150 deg^2^ Canada-France-Hawaii Telescope Legacy Survey (CFHTLS). We describe each of the steps of RINGFINDER. We then carry out extensive simulations to assess completeness and purity. For sources with magnification {mu}>4, RINGFINDER reaches 42% (25%) completeness and 29% (86%) purity before (after) visual inspection. The completeness of RINGFINDER is substantially improved in the particular range of Einstein radii 0.8"<=R_Ein_<=2.0" and lensed images brighter than g=22.5, where it can be as high as ~70%. RINGFINDER does not introduce any significant bias in the source or deflector population. We conclude by presenting the final catalog of RINGFINDER CFHTLS galaxy-scale strong lens candidates. Additional information obtained with Hubble Space Telescope and Keck adaptive optics high-resolution imaging, and with Keck and Very Large Telescope spectroscopy, is used to assess the validity of our classification and measure the redshift of the foreground and the background objects. From an initial sample of 640000 ETGs, RINGFINDER returns 2500 candidates, which we further reduce by visual inspection to 330 candidates. We confirm 33 new gravitational lenses from the main sample of candidates, plus an additional 16 systems taken from earlier versions of RINGFINDER. First applications are presented in the Strong Lensing Legacy Survey galaxy-scale lens sample paper series.
678. Small Drift Scan Survey Galaxies Northern Sky
ID:
ivo://CDS.VizieR/J/AJ/105/393
Title:
Small Drift Scan Survey Galaxies Northern Sky
Short Name:
J/AJ/105/393
Date:
21 Oct 2021
Publisher:
CDS
Description:
The file is an ASCII text file containing data for 1053 galaxies brighter than 18.0 mag. in the filter used. The effective wavelength of this filter for objects that have the color of galaxies closely matches that of Thuan and Gunn r filter. The strip covered in the survey is 12 arcmin wide by 60 degree long. The observations were carried out on the night of 23 May 1990, using the drift scanning technique, with the 24 inch telescope of the Whipple Observatory. The effective integration time was 57 s.
679. SN host galaxies basic information
ID:
ivo://CDS.VizieR/J/ApJ/791/57
Title:
SN host galaxies basic information
Short Name:
J/ApJ/791/57
Date:
21 Oct 2021
Publisher:
CDS
Description:
We compare the host galaxies of 902 supernovae (SNe), including SNe Ia, SNe II, and SNe Ibc, which are selected by cross-matching the Asiago Supernova Catalog (Barbon et al., cat II/227) with the Sloan Digital Sky Survey (SDSS) Data Release 7 (Strauss et al., 2002AJ....124.1810S). We selected an additional 213 galaxies by requiring the light fraction of spectral observations to be >15%, which could represent well the global properties of the galaxies. Among these 213 galaxies, 135 appear on the Baldwin-Phillips-Terlevich diagram, which allows us to compare the hosts in terms of whether they are star-forming (SF) galaxies, active galactic nuclei (AGNs; including composites, LINERs, and Seyfert 2s) or absorption-line galaxies (Absorps; i.e., their related emission lines are weak or non-existent). The diagrams related to the parameters D_n_(4000), H{delta}_A_, stellar masses, star formation rates (SFRs), and specific SFRs for the SNe hosts show that almost all SNe II and most of the SNe Ibc occur in SF galaxies, which have a wide range of stellar masses and low D_n_(4000). The SNe Ia hosts as SF galaxies following similar trends. A significant fraction of SNe Ia occurs in AGNs and absorption-line galaxies, which are massive and have high D_n_(4000). The stellar population analysis from spectral synthesis fitting shows that the hosts of SNe II have a younger stellar population than hosts of SNe Ia. These results are compared with those of the 689 comparison galaxies where the SDSS fiber captures less than 15% of the total light. These comparison galaxies appear biased toward higher 12+log(O/H) (~0.1 dex) at a given stellar mass. Therefore, we believe the aperture effect should be kept in mind when the properties of the hosts for different types of SNe are discussed.
680. Sou323 ICRF reference sample
ID:
ivo://CDS.VizieR/J/MNRAS/466/1567
Title:
Sou323 ICRF reference sample
Short Name:
J/MNRAS/466/1567
Date:
21 Oct 2021
Publisher:
CDS
Description:
We aim to evaluate the possibility of improving the International Celestial Reference System realization starting from the ICRF2 catalogue by investigating the coordinate time series of radio sources observed by the very long baseline interferometry between 1979 and 2016. Sources with long observational history are selected as the candidates and the least-squares fits with special handling of the weights are performed to derive the linear drifts of the source coordinates. Then the sources are sorted, based on the normalized linear drift (i) over the whole sky, and (ii) in four homolographic areas divided by declinations. The axial stability of the reference system and sky distribution defined by the selected sources are evaluated, which are acted as the criterion for the final source lists. With our improved source selection scheme, two groups of sources are proposed and considered suitable for defining a more stable and homogeneous celestial reference system compared to the second version of the current International Celestial Reference Frame (ICRF2). The number of sources in the final lists are 323 and 294, respectively, and the global rotations of the axes derived from apparent motion of the sources are about two times better th

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