- ID:
- ivo://CDS.VizieR/J/ApJS/239/32
- Title:
- APOKASC-2 catalog of Kepler evolved stars
- Short Name:
- J/ApJS/239/32
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a catalog of stellar properties for a large sample of 6676 evolved stars with Apache Point Observatory Galactic Evolution Experiment spectroscopic parameters and Kepler asteroseismic data analyzed using five independent techniques. Our data include evolutionary state, surface gravity, mean density, mass, radius, age, and the spectroscopic and asteroseismic measurements used to derive them. We employ a new empirical approach for combining asteroseismic measurements from different methods, calibrating the inferred stellar parameters, and estimating uncertainties. With high statistical significance, we find that asteroseismic parameters inferred from the different pipelines have systematic offsets that are not removed by accounting for differences in their solar reference values. We include theoretically motivated corrections to the large frequency spacing ({Delta}{nu}) scaling relation, and we calibrate the zero-point of the frequency of the maximum power ({nu}max) relation to be consistent with masses and radii for members of star clusters. For most targets, the parameters returned by different pipelines are in much better agreement than would be expected from the pipeline-predicted random errors, but 22% of them had at least one method not return a result and a much larger measurement dispersion. This supports the usage of multiple analysis techniques for asteroseismic stellar population studies. The measured dispersion in mass estimates for fundamental calibrators is consistent with our error model, which yields median random and systematic mass uncertainties for RGB stars of order 4%. Median random and systematic mass uncertainties are at the 9% and 8% level, respectively, for red clump stars.
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- ID:
- ivo://CDS.VizieR/J/ApJS/215/19
- Title:
- APOKASC catalog of Kepler red giants
- Short Name:
- J/ApJS/215/19
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the first APOKASC catalog of spectroscopic and asteroseismic properties of 1916 red giants observed in the Kepler fields. The spectroscopic parameters provided from the Apache Point Observatory Galactic Evolution Experiment project are complemented with asteroseismic surface gravities, masses, radii, and mean densities determined by members of the Kepler Asteroseismology Science Consortium. We assess both random and systematic sources of error and include a discussion of sample selection for giants in the Kepler fields. Total uncertainties in the main catalog properties are of the order of 80K in T_eff_, 0.06dex in [M/H], 0.014dex in logg, and 12% and 5% in mass and radius, respectively; these reflect a combination of systematic and random errors. Asteroseismic surface gravities are substantially more precise and accurate than spectroscopic ones, and we find good agreement between their mean values and the calibrated spectroscopic surface gravities. There are, however, systematic underlying trends with T_eff_ and logg. Our effective temperature scale is between 0 and 200K cooler than that expected from the infrared flux method, depending on the adopted extinction map, which provides evidence for a lower value on average than that inferred for the Kepler Input Catalog (KIC). We find a reasonable correspondence between the photometric KIC and spectroscopic APOKASC metallicity scales, with increased dispersion in KIC metallicities as the absolute metal abundance decreases, and offsets in T_eff_ and logg consistent with those derived in the literature. We present mean fitting relations between APOKASC and KIC observables and discuss future prospects, strengths, and limitations of the catalog data.
- ID:
- ivo://CDS.VizieR/J/ApJS/233/23
- Title:
- APOKASC catalog of KIC dwarfs and subgiants
- Short Name:
- J/ApJS/233/23
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the first APOKASC catalog of spectroscopic and asteroseismic data for dwarfs and subgiants. Asteroseismic data for our sample of 415 objects have been obtained by the Kepler mission in short (58.5s) cadence, and light curves span from 30 up to more than 1000 days. The spectroscopic parameters are based on spectra taken as part of the Apache Point Observatory Galactic Evolution Experiment (APOGEE) and correspond to Data Release 13 of the Sloan Digital Sky Survey. We analyze our data using two independent T_eff_ scales, the spectroscopic values from DR13 and those derived from SDSS griz photometry. We use the differences in our results arising from these choices as a test of systematic temperature uncertainties and find that they can lead to significant differences in the derived stellar properties. Determinations of surface gravity (logg), mean density (<{rho}>), radius (R), mass (M), and age ({tau}) for the whole sample have been carried out by means of (stellar) grid-based modeling. We have thoroughly assessed random and systematic error sources in the spectroscopic and asteroseismic data, as well as in the grid-based modeling determination of the stellar quantities provided in the catalog. We provide stellar properties determined for each of the two T_eff_ scales. The median combined (random and systematic) uncertainties are 2% (0.01dex; logg), 3.4% (<{rho}>), 2.6% (R), 5.1% (M), and 19% ({tau}) for the photometric T_eff_ scale and 2% (logg), 3.5% (<{rho}>), 2.7% (R), 6.3% (M), and 23% ({tau}) for the spectroscopic scale.
- ID:
- ivo://CDS.VizieR/J/A+A/658/A158
- Title:
- A polarimetric study of ACOs
- Short Name:
- J/A+A/658/A158
- Date:
- 22 Feb 2022 15:07:47
- Publisher:
- CDS
- Description:
- Asteroids in comet-like orbits (ACOs) consist of asteroids and dormant comets. Due to their similar appearance, it is challenging to distinguish dormant comets from ACOs via general telescopic observations. Surveys for discriminating dormant comets from the ACO population have been conducted via spectroscopy or optical and mid-infrared photometry. However, they have not been conducted through polarimetry. We conducted the first polarimetric research of ACOs. We conducted a linear polarimetric pilot survey for three ACOs: (944) Hidalgo, (3552) Don Quixote, and (331471) 1984 QY1. These objects are unambiguously classified into ACOs in terms of their orbital elements (i.e., the Tisserand parameters with respect to Jupiter TJ significantly less than 3). Three ACOs were observed by the 1.6-m Pirka Telescope from UT 2016 May 25 to UT 2019 July 22 (13 nights). We found that two ACOs, Don Quixote and Hidalgo, have polarimetric properties similar to comet nuclei and D-type asteroids (optical analogs of comet nuclei. However, 1984 QY1 exhibited a polarimetric property consistent with S-type asteroids. We conducted a backward orbital integration to determine the origin of 1984 QY1 and found that this object was transported from the main belt into the current comet-like orbit via the 3:1 mean motion resonance with Jupiter. We conclude that the origins of ACOs can be more reliably identified by adding polarimetric data to the color and spectral information. This study would be valuable for investigating how the ice-bearing small bodies distribute in the inner solar system.
- ID:
- ivo://CDS.VizieR/J/ApJ/731/123
- Title:
- APOSTLE light curve of GJ 1214b
- Short Name:
- J/ApJ/731/123
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present three transits of GJ 1214b, observed as part of the Apache Point Observatory Survey of Transit Light Curves of Exoplanets (APOSTLE). By applying Markov Chain Monte Carlo techniques to a multi-wavelength data set which included our r-band light curves and previously gathered data of GJ 1214b, we confirm earlier estimates of system parameters. Using spectral energy distribution fitting, mass-luminosity relations, and light curve data, we derived absolute parameters for the star and planet, improving uncertainties by a factor of two for the stellar mass (M_*_=0.153^+0.010^_-0.009_M_{sun}_), stellar radius (R_*_=0.210^+0.005^_-0.004R_{sun}_), planetary radius (R_p_=2.74^+0.06^_-0.05_R_{earth}_), and planetary density ({rho}_p_=1.68+/-0.23g/cm^3^). Transit times derived from our study show no evidence for strong transit timing variations. We also report the detection of two features in our light curves which we believe are evidence for a low-energy stellar flare and a spot-crossing event.
- ID:
- ivo://CDS.VizieR/J/ApJ/764/8
- Title:
- APOSTLE r'-band transit lightcurves of TrES-3b
- Short Name:
- J/ApJ/764/8
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Apache Point Survey of Transit Lightcurves of Exoplanets (APOSTLE) observed 11 transits of TrES-3b over two years in order to constrain system parameters and look for transit timing and depth variations. We describe an updated analysis protocol for APOSTLE data, including the reduction pipeline, transit model, and Markov Chain Monte Carlo analyzer. Our estimates of the system parameters for TrES-3b are consistent with previous estimates to within the 2{sigma} confidence level. We improved the errors (by 10%-30%) on system parameters such as the orbital inclination (i_orb_), impact parameter (b), and stellar density ({rho}_{sstarf}_) compared to previous measurements. The near-grazing nature of the system, and incomplete sampling of some transits, limited our ability to place reliable uncertainties on individual transit depths and hence we do not report strong evidence for variability. Our analysis of the transit timing data shows no evidence for transit timing variations and our timing measurements are able to rule out super-Earth and gas giant companions in low-order mean motion resonance with TrES-3b.
- ID:
- ivo://CDS.VizieR/J/ApJ/770/36
- Title:
- APOSTLE transits of XO-2 system
- Short Name:
- J/ApJ/770/36
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Apache Point Survey of Transit Lightcurves of Exoplanets (APOSTLE) observed 10 transits of XO-2b over a period of 3yr. We present measurements that confirm previous estimates of system parameters like the normalized semi-major axis (a/R_*_), stellar density ({rho}_*_), impact parameter (b), and orbital inclination (i_orb_). Our errors on system parameters like a/R_*_ and {rho}_*_ have improved by ~40% compared to previous best ground-based measurements. Our study of the transit times show no evidence for transit timing variations (TTVs) and we are able to rule out co-planar companions with masses >=0.20M_{Earth}_ in low order mean motion resonance with XO-2b. We also explored the stability of the XO-2 system given various orbital configurations of a hypothetical planet near the 2:1 mean motion resonance. We find that a wide range of orbits (including Earth-mass perturbers) are both dynamically stable and produce observable TTVs. We find that up to 51% of our stable simulations show TTVs that are smaller than the typical transit timing errors (~20s) measured for XO-2b, and hence remain undetectable.
- ID:
- ivo://CDS.VizieR/II/155
- Title:
- Apparent Diameters and Absolute Radii of Stars
- Short Name:
- II/155
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- For 7255 stars this catalog lists all values of the apparent and absolute radii from the literature. Data were compiled beginning 1950 up to 1985, including some data from 1986 and 1987. The catalogue was ordered by identification by HD number or BD number followed by variables with constellation names in alphabetical order, followed by other abbreviations. The HD and BD numbers were given priority 1 and 2 respectively over the other identifications. Hence variable stars can be found under the name of the constellation only when HD and BD numbers are lacking. The apparent magnitudes and spectral types are those reported by the authors, as they are basic data used in some methods for obtaining the stellar diameters.
- ID:
- ivo://CDS.VizieR/J/ApJ/712/585
- Title:
- Apparent velocity measurements of DA WDs
- Short Name:
- J/ApJ/712/585
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We measure apparent velocities (v_app_) of the H{alpha} and H{beta} Balmer line cores for 449 non-binary thin disk normal DA white dwarfs (WDs) using optical spectra taken for the European Southern Observatory SN Ia progenitor survey (SPY). Assuming these WDs are nearby and comoving, we correct our velocities to the local standard of rest so that the remaining stellar motions are random. By averaging over the sample, we are left with the mean gravitational redshift, <v_g_>: we find <v_g_>=<v_app_>=32.57+/-1.17km/s. Using the mass-radius relation from evolutionary models, this translates to a mean mass of 0.647^+0.013^_-0.014_M_{sun}_. We interpret this as the mean mass for all DAs.
- ID:
- ivo://www.plate-archive.org/tap
- Title:
- APPLAUSE - Archives of Photographic PLates for Astronomical USE TAP Service
- Date:
- 28 Dec 2023
- Publisher:
- Leibniz Institute for Astrophysics Potsdam (AIP)
- Description:
- The TAP Service registry for www.plate-archive.org.
