- ID:
- ivo://CDS.VizieR/J/MNRAS/419/L34
- Title:
- Surface gravity determination in late-type stars
- Short Name:
- J/MNRAS/419/L34
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The frequency of maximum oscillation power measured in dwarfs and giants exhibiting solar-like pulsations provides a precise, and potentially accurate, inference of the stellar surface gravity. An extensive comparison for about 40 well-studied pulsating stars with gravities derived using classical methods (ionization balance, pressure-sensitive spectral features or location with respect to evolutionary tracks) supports the validity of this technique and reveals an overall remarkable agreement with mean differences not exceeding 0.05dex (although with a dispersion of up to ~0.2dex). It is argued that interpolation in theoretical isochrones may be the most precise way of estimating the gravity by traditional means in nearby dwarfs. Attention is drawn to the usefulness of seismic targets as benchmarks in the context of large-scale surveys.
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- ID:
- ivo://CDS.VizieR/J/ApJ/783/123
- Title:
- Surface gravity for 220 Kepler stars
- Short Name:
- J/ApJ/783/123
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a novel method for estimating lower-limit surface gravities (logg) of Kepler targets whose data do not allow the detection of solar-like oscillations. The method is tested using an ensemble of solar-type stars observed in the context of the Kepler Asteroseismic Science Consortium. We then proceed to estimate lower-limit log g for a cohort of Kepler solar-type planet-candidate host stars with no detected oscillations. Limits on fundamental stellar properties, as provided by this work, are likely to be useful in the characterization of the corresponding candidate planetary systems. Furthermore, an important byproduct of the current work is the confirmation that amplitudes of solar-like oscillations are suppressed in stars with increased levels of surface magnetic activity.
- ID:
- ivo://CDS.VizieR/J/AJ/149/157
- Title:
- Surface intensity profiles for 10 M33 globular clusters
- Short Name:
- J/AJ/149/157
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In this paper, we present the properties of 10 halo globular clusters (GCs) with luminosities L~=5-7x10^5^L_{sun}_ in the Local Group galaxy M33 using images from the Hubble Space Telescope WFPC2 in the F555W and F814W bands. We obtained the ellipticities, position angles, and surface brightness profiles for each GC. In general, the ellipticities of the M33 sample clusters are similar to those of the M31 clusters. The structural and dynamical parameters are derived by fitting the profiles to three different models combined with mass-to-light ratios (M/L values) from population-synthesis models. The structural parameters include core radii, concentration, half-light radii, and central surface brightness. The dynamical parameters include the integrated cluster mass, integrated binding energy, central surface mass density, and predicted line of sight velocity dispersion at the cluster center. The velocity dispersions of the four clusters predicted here agree well with the observed dispersions by Larsen et al. The results here showed that the majority of the sample halo GCs are better fitted by both the King model and the Wilson model than the Sersic model. In general, the properties of the clusters in M33, M31, and the Milky Way fall in the same regions of parameter spaces. The tight correlations of cluster properties indicate a "fundamental plane" for clusters, which reflects some universal physical conditions and processes operating at the epoch of cluster formation.
- ID:
- ivo://CDS.VizieR/J/A+A/387/26
- Title:
- Surface photometry in 7 nearby clusters
- Short Name:
- J/A+A/387/26
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This is the first paper of a series investigating the scaling relations of early-type galaxies in clusters. Here we illustrate the multi-band imagery and the image reduction and calibration procedures relative to the whole sample of 22 clusters at 0.05<~z<~0.25. We also present detailed surface photometry of 312 early-type galaxies in 7 clusters (A1069, A119, A1983, A2151, A2670, A3125 and DC2103) in the first redshift bin, z=0.025-0.075. We give for each galaxy the complete set of luminosity and geometrical profiles, and a number of global, photometric and morphological parameters. They have been evaluated taking into account the effects of seeing. Internal consistency checks and comparisons with data in the literature confirm the quality of our analysis. These data, together with the spectroscopic ones presented in the second paper of the series, will provide the local calibration of the scaling relations.
- ID:
- ivo://CDS.VizieR/J/ApJS/156/345
- Title:
- Surface photometry of BCD galaxies
- Short Name:
- J/ApJS/156/345
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results from an analysis of surface photometry of B, R, and H{alpha} images of a total of 114 nearby galaxies (v_helio_<4000km/s) drawn from the Palomar/Las Campanas Imaging Atlas of blue compact dwarf (BCD) galaxies. Surface brightness and color profiles for the complete sample have been obtained. We determine the exponential and Sersic profiles that best fit the surface brightness distribution of the underlying stellar population detected in these galaxies. We also compute the (B-R) color and total absolute magnitude of the underlying stellar population and compared them to the integrated properties of the galaxies in the sample.
- ID:
- ivo://CDS.VizieR/J/ApJ/517/650
- Title:
- Surface photometry of dwarf galaxies in Virgo
- Short Name:
- J/ApJ/517/650
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We analyze new V-band images of 14 dwarf S0 galaxies and 10 dwarf elliptical galaxies in the Virgo Cluster, in combination with R-band images of 70 dwarf elliptical galaxies from an earlier paper. We compute the intensity-weighted mean ellipticity, the mean deviations from elliptical isophotes, and a newly defined parameter to measure isophotal twists. We also fit each major-axis profile to a power law {Sigma}(a) {prop.to} exp[-(a/a_s_)^n^], where n is allowed to vary. Consistent with other studies of the Virgo dwarf ellipticals, we find that the profile shapes for the entire sample is strongly peaked near n=1 (exponential profiles) and that no galaxies have n=1/4 (de Vaucouleurs profile). The faintest galaxies all have nearly exponential profiles, while the brighter ones on average have n<1. The correlation between ellipticity and the boxy/disky parameter is similar to that of large elliptical galaxies, suggesting that dwarfs may also be divided into two groups with differing internal dynamics. The Virgo dEs also show a greater degree of isophotal twisting than more luminous elliptical galaxies.
- ID:
- ivo://CDS.VizieR/VII/115
- Title:
- Surface Photometry of ESO-Uppsala Galaxies
- Short Name:
- VII/115
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The 15467 southern galaxies in this catalog were scanned from 407 blue and 407 red original ESO-Schmidt plates using a PDS microdensitometer. The galaxies were selected from the ESO-Uppsala Catalogue (VII/34). The original selection criterion was a minimum visual angular diameter of 1arcmin. The plates were calibrated using a catalog of photo- electric standards of 1700 standard galaxies transformed to a photometric standard system (Cousins) created by the authors. The result is a catalog acquired in a homogeneous fashion for all types of galaxies in various environments. The extracted parameters include radial surface brightness profiles, magnitudes at several isophotal levels, colors, color gradients, effective radius parameters, structural parameters such as axial ratios, position angles, and profile gradients. The full version of the catalog, made of 190 columns, is available as the file "esolv.fit" in FITS table format. The ascii file "esolv1.dat" contains a subset of these columns which includes those parameters listed in the printed book version. Detailed discussion of the catalog creation is given in the published book version (ISBN 3-923524-31-5)
- ID:
- ivo://CDS.VizieR/J/MNRAS/453/2965
- Title:
- Surface photometry of GHASP galaxies
- Short Name:
- J/MNRAS/453/2965
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present Rc-band surface photometry for 170 of the 203 galaxies in GHASP, the Gassendi H-alpha survey of spirals, a sample of late-type galaxies for which high-resolution Fabry-Perot H{alpha} maps have previously been obtained.
- ID:
- ivo://CDS.VizieR/J/ApJS/85/249
- Title:
- Surface Photometry of Hydra I Galaxies. I.
- Short Name:
- J/ApJS/85/249
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Surface photometry was made for 137 galaxies on a UK Schmidt plate whose center is located at the center of the Hydra I (A1060) cluster of galaxies. For 133 of 137 galaxies the photometric parameters such as total magnitude, equivalent radius, concentration indices, and mean surface brightness were obtained. The total magnitudes were compared with those in the literature to check the accuracy of the present data. The estimated accuracy in the total magnitudes is about 0.1 mag at most for majority of the galaxies. This catalog is an updated version from the published paper.
- ID:
- ivo://CDS.VizieR/J/MNRAS/384/1544
- Title:
- Surface photometry of local dwarf galaxies
- Short Name:
- J/MNRAS/384/1544
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present surface photometry and metallicity measurements for 104 nearby dwarf galaxies imaged with the Advanced Camera for Surveys and Wide Field and Planetary Camera 2 aboard the Hubble Space Telescope. In addition, we carried out photometry for 26 galaxies of the sample and for Sextans B on images of the Sloan Digital Sky Survey. Our sample comprises dwarf spheroidal, irregular and transition type galaxies located within ~10Mpc in the field and in nearby groups: M81, Centaurus A, Sculptor and Canes Venatici I cloud. It is found that the early-type galaxies have on average higher metallicity at a given luminosity in comparison to the late-type objects. Dwarf galaxies with MB>=-12 to -13mag deviate towards larger scalelengths from the scalelength-luminosity relation common for spiral galaxies, h{prop.to}L^0.5^_B_.