- ID:
- ivo://CDS.VizieR/J/A+A/569/A15
- Title:
- KIC 10553698A asteroseismology
- Short Name:
- J/A+A/569/A15
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The subdwarf-B pulsator, KIC10553698A, is one of 16 such objects observed with one-minute sampling for most of the duration of the Kepler Mission. Like most of these stars, it displays a rich g-mode pulsation spectrum with several clear multiplets that maintain regular frequency splitting. We identify these pulsation modes as components of rotationally split multiplets in a star rotating with a period of ~41d. From 162 clearly significant periodicities, we are able to identify 156 as likely components of l=1 or l=2 multiplets. For the first time we are able to detect l=1 modes that interpose in the asymptotic period sequences and that provide a clear indication of mode trapping in a stratified envelope, as predicted by theoretical models. A clear signal is also present in the Kepler photometry at 3.387d. Spectroscopic observations reveal a radial-velocity amplitude of 64.8km/s. We find that the radial-velocity variations and the photometric signal have phase and amplitude that are perfectly consistent with a Doppler-beaming effect and conclude that the unseen companion, KIC10553698B, must be a white dwarf most likely with a mass close to 0.6M_{sun}_.
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- ID:
- ivo://CDS.VizieR/J/ApJ/831/11
- Title:
- KIC 9777062 RVs & asteroseismology in NGC6811
- Short Name:
- J/ApJ/831/11
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the analysis of an eccentric, partially eclipsing long-period (P=19.23 days) binary system KIC 9777062 that contains main-sequence stars near the turnoff of the intermediate-age open cluster NGC 6811. The primary is a metal-lined Am star with a possible convective blueshift to its radial velocities, and one star (probably the secondary) is likely to be a {gamma} Dor pulsator. The component masses are 1.603+/-0.006(stat.)+/-0.016(sys.) and 1.419+/-0.003+/-0.008M_{sun}_, and the radii are 1.744+/-0.004+/-0.002 and 1.544+/-0.002+/-0.002R_{sun}_. The isochrone ages of the stars are mildly inconsistent: the age from the mass-radius combination for the primary (1.05+/-0.05+/-0.09Gyr, where the last quote was systematic uncertainty from models and metallicity) is smaller than that from the secondary (1.21+/-0.05+/-0.15Gyr) and is consistent with the inference from the color-magnitude diagram (1.00+/-0.05Gyr). We have improved the measurements of the asteroseismic parameters {Delta}{nu} and {nu}_max_ for helium-burning stars in the cluster. The masses of the stars appear to be larger (or alternately, the radii appear to be smaller) than predicted from isochrones using the ages derived from the eclipsing stars. The majority of stars near the cluster turnoff are pulsating stars: we identify a sample of 28 {delta} Sct, 15 {gamma} Dor, and 5 hybrid types. We used the period-luminosity relation for high-amplitude {delta} Sct stars to fit the ensemble of the strongest frequencies for the cluster members, finding (m-M)_V_=10.37+/-0.03. This is larger than most previous determinations, but smaller than values derived from the eclipsing binary (10.47+/-0.05).
- ID:
- ivo://CDS.VizieR/J/A+AS/122/521
- Title:
- Kinematical data on early-type galaxies. I.
- Short Name:
- J/A+AS/122/521
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- As part of an ongoing program on the main parameters of early-type galaxies, we have performed long-slit absorption spectroscopy on a sample of 21 ellipticals and S0s. We present determinations of the central velocity dispersion and, for 18 objects, velocity-dispersion profiles and rotation curves.
- ID:
- ivo://CDS.VizieR/J/A+AS/126/15
- Title:
- Kinematical data on early-type galaxies. II.
- Short Name:
- J/A+AS/126/15
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present new kinematical data for a sample of 38 early-type galaxies. Rotation curves and velocity-dispersion profiles are determined for 32 objects, while the central velocity dispersions are given for the whole sample. This is our second paper in a series devoted to the presentation of kinematical data on elliptical and S0 galaxies, derived from long-slit absorption spectroscopy.
- ID:
- ivo://CDS.VizieR/J/A+AS/126/519
- Title:
- Kinematical data on early-type galaxies. III.
- Short Name:
- J/A+AS/126/519
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present new kinematical data for a sample of 24 early-type galaxies. Rotation curves and velocity-dispersion profiles are determined for 21 objects, while the central velocity dispersions are given for the whole sample. This is our third paper in a series devoted to the presentation of kinematical data on elliptical and S0 galaxies, derived from long-slit absorption spectroscopy.
- ID:
- ivo://CDS.VizieR/J/A+AS/131/287
- Title:
- Kinematical data on early-type galaxies. IV.
- Short Name:
- J/A+AS/131/287
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present kinematical data for a sample of 25 galaxies. Rotation curves and velocity-dispersion profiles are determined for 16 objects, while the central velocity dispersions are given for the whole sample. This is our fourth paper in a series devoted to the presentation of kinematical data on elliptical and S0 galaxies, derived from long-slit absorption spectroscopy.
- ID:
- ivo://CDS.VizieR/J/A+AS/145/263
- Title:
- Kinematical data on early-type galaxies. V.
- Short Name:
- J/A+AS/145/263
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present kinematical data for a sample of 26 galaxies. Rotation curves and velocity-dispersion profiles are determined for all objects. This is our fifth paper in a series devoted to the presentation of data on elliptical and S0 galaxies, derived from long-slit absorption spectroscopy; the series now gathers 119 galaxies with homogeneous data.
- ID:
- ivo://CDS.VizieR/J/A+A/384/371
- Title:
- Kinematical data on early-type galaxies. VI
- Short Name:
- J/A+A/384/371
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the result of spectroscopic observations of a sample of 73 galaxies, completing the database published in this series of articles. The sample contains mostly low-luminosity early-type objects, including four dwarfs of the Local Group (in particular, deep spectra of NGC 205), 15 dEs or dS0s in the Virgo cluster, and UGC 05442, a spheroidal dwarf of the M81 group. We have measured the central velocity dispersion for all but one object, and determined the major-axis rotation and velocity-dispersion profiles for 59 objects. For the current sample of diffuse (or dwarf) elliptical galaxies, we have compared stellar rotation to velocity dispersion; the analysis suggests that these objects may be nearly rotationally flattened, and therefore that anisotropy may be less important than previously thought.
- ID:
- ivo://CDS.VizieR/J/ApJ/761/34
- Title:
- Kinematical study of the optical ejecta of GK Per
- Short Name:
- J/ApJ/761/34
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a kinematical study of the optical ejecta of GK Per. It is based on proper-motion measurements of 282 knots from ~20 images spanning 25 years. Doppler shifts are also computed for 217 knots. The combination of proper motions and radial velocities allows a unique three-dimensional view of the ejecta to be obtained. The main results are as follows: (1) the outflow is a thick shell in which knots expand with a significant range of velocities, mostly between 600 and 1000 km/s, (2) kinematical ages indicate that knots have suffered only a modest deceleration since their ejection a century ago, (3) no evidence for anisotropy in the expansion rate is found, (4) velocity vectors are generally aligned along the radial direction, but a symmetric pattern of non-radial velocities is also observed at specific directions, and (5) the total H{alpha}+[N II] flux has been linearly decreasing at a rate of 2.6% per year in the past decade. The eastern nebular side is fading at a slower rate than the western side. Some of the knots were displayed a rapid change of brightness during the 2004-2011 period. Over a longer timescale, a progressive circularization and homogenization of the nebula are taking place; (6) a kinematic distance of 400+/-30 pc is determined. These results raise some problems with the previous interpretations of the evolution of GK Per. In particular, the idea of a strong interaction of the outflow with the surrounding medium in the southwest quadrant is not supported by our data.
- ID:
- ivo://CDS.VizieR/J/ApJS/225/10
- Title:
- Kinematic analysis of M7-L8 dwarfs
- Short Name:
- J/ApJS/225/10
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a kinematic analysis of 152 low surface gravity M7-L8 dwarfs by adding 18 new parallaxes (including 10 for comparative field objects), 38 new radial velocities, and 19 new proper motions. We also add low- or moderate-resolution near-infrared spectra for 43 sources confirming their low surface gravity features. Among the full sample, we find 39 objects to be high-likelihood or new bona fide members of nearby moving groups, 92 objects to be ambiguous members and 21 objects that are non-members. Using this age-calibrated sample, we investigate trends in gravity classification, photometric color, absolute magnitude, color-magnitude, luminosity, and effective temperature.