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3701. T1C photometry of NGC7507
ID:
ivo://CDS.VizieR/J/A+A/555/A56
Title:
T1C photometry of NGC7507
Short Name:
J/A+A/555/A56
Date:
21 Oct 2021
Publisher:
CDS
Description:
There is strong evidence that globular cluster systems (GCSs) of massive galaxies are largely assembled by infall/accretion processes. Therefore, we expect the GCSs of isolated elliptical galaxies to be poor. Although not completely isolated, NGC 7507 is a massive field elliptical galaxy with an apparently very low dark matter content. We determine the richness, the colour distribution, and the structural properties of the GCS of NGC 7507. We performed wide-field Washington photometry with data obtained with the MOSAIC II camera at the 4m-Blanco telescope (CTIO, Chile).
3702. Teff and metallicities for Tycho-2 stars
ID:
ivo://CDS.VizieR/V/136
Title:
Teff and metallicities for Tycho-2 stars
Short Name:
V/136
Date:
21 Oct 2021
Publisher:
CDS
Description:
We have created specialized target lists for radial velocity surveys that are biased toward stars that (1) possess planets and (2) are easiest to observe with current detection techniques. We use a procedure that uniformly estimates fundamental stellar properties of Tycho 2 stars, with errors, using spline functions of broadband photometry and proper motion found in Hipparcos/Tycho 2 and 2MASS. We provide estimates of effective temperature and distance for 2.4 million Tycho 2 stars that lack trigonometric distances. For stars that appear to be FGK dwarfs, we also derive [Fe/H] and identify unresolved binary systems with mass ratios 1.25<M1/M2<3.0. For FGK dwarfs with photometric error {sigma}_V_<0.05, or V<9, our temperature model gives a 1{sigma} error of {sigma}_T_=+58.7/-65.9K and our metallicity model gives a 1{sigma} error of {sigma}_[Fe/H]_=+0.13/-0.14dex. The binarity model can be used to remove 70% of doubles with 1.25<M1/M2<3.0 from a magnitude-limited sample of dwarfs at a cost of cutting 20% of the sample. Our estimates of distance and spectral type enable us to isolate 354,822 Tycho 2 dwarfs, 321,996 absent from Hipparcos, with giant contamination of 2.6% and 7.2%, respectively. Roughly 100,000 of these stars, not in Hipparcos, have sufficiently low photometric errors to retain 0.13-0.3dex [Fe/H] accuracy and 80-100K temperature accuracy (1{sigma}). Our metallicity estimates have been used to identify targets for N2K, a large-scale radial velocity search for hot jupiters, which has verified the errors presented here. The catalogs that we publish can be used to further large-scale studies of Galactic structure and chemical evolution and to provide potential reference stars for narrow-angle astrometry programs such as the Space Interferometry Mission and large-aperture optical interferometry.
3703. Teff and metallicities of M dwarfs in APOGEE DR14
ID:
ivo://CDS.VizieR/J/ApJ/892/31
Title:
Teff and metallicities of M dwarfs in APOGEE DR14
Short Name:
J/ApJ/892/31
Date:
07 Mar 2022 13:23:27
Publisher:
CDS
Description:
M dwarfs have enormous potential for our understanding of structure and formation on both Galactic and exoplanetary scales through their properties and compositions. However, current atmosphere models have limited ability to reproduce spectral features in stars at the coolest temperatures (Teff<4200K) and to fully exploit the information content of current and upcoming large-scale spectroscopic surveys. Here we present a catalog of spectroscopic temperatures, metallicities, and spectral types for 5875 M dwarfs in the Apache Point Observatory Galactic Evolution Experiment (APOGEE) and Gaia-DR2 surveys using The Cannon (Ness+ 2015, J/ApJ/808/16 ; Casey+ 2016, arXiv:1603.03040; Ho+ 2017, J/ApJ/836/5; Behmard+ 2019ApJ...876...68B): a flexible, data-driven spectral-modeling and parameter-inference framework demonstrated to estimate stellar-parameter labels (Teff, logg, [Fe/H], and detailed abundances) to high precision. Using a training sample of 87 M dwarfs with optically derived labels spanning 2860K<Teff<4130K calibrated with bolometric temperatures, and -0.5<[Fe/H]<0.5dex calibrated with FGK binary metallicities, we train a two-parameter model with predictive accuracy (in cross-validation) to 77K and 0.09dex respectively. We also train a one-dimensional spectral classification model using 51 M dwarfs with Sloan Digital Sky Survey optical spectral types ranging from M0 to M6, to predictive accuracy of 0.7 types. We find Cannon temperatures to be in agreement to within 60 K compared to a subsample of 1702 sources with color-derived temperatures, and Cannon metallicities to be in agreement to within 0.08 dex metallicity compared to a subsample of 15 FGK+M or M+M binaries. Finally, our comparison between Cannon and APOGEE pipeline (ASPCAP DR14) labels finds that ASPCAP is systematically biased toward reporting higher temperatures and lower metallicities for M dwarfs.
3704. Temperature catalog of class IV-V stars
ID:
ivo://CDS.VizieR/J/A+A/398/721
Title:
Temperature catalog of class IV-V stars
Short Name:
J/A+A/398/721
Date:
21 Oct 2021
Publisher:
CDS
Description:
The catalog contains values of theta [= 5040/T_eff_] for 951 F-K stars which are on or near the main sequence. Values of Cousins R-I are also given for most stars.
3705. Temperatures and Rc photometry in the Hyades
ID:
ivo://CDS.VizieR/J/ApJS/159/100
Title:
Temperatures and Rc photometry in the Hyades
Short Name:
J/ApJS/159/100
Date:
21 Oct 2021
Publisher:
CDS
Description:
Using Hyades photometry published by Mendoza (1967BOTT....4..149M) and other authors, Pinsonneault et al. (2004ApJ...600..946P) have recently concluded that Cousins V-I photometry published by Taylor & Joner (1985AJ.....90..479T, 1988AJ.....96..211T, 1996AJ....111.1338T) is not on the Cousins system. Extensive tests of the Taylor-Joner photometry and other pertinent results are therefore performed in this paper. It is found that in part, the Pinsonneault et al. conclusion rests on (1) a systematic error in Mendoza's (R-I)J photometry and (2) a small error in an approximate Johnson-to-Cousins transformation published by Bessell. For the Taylor-Joner values of (V-R)C, it is found that there are possible (though not definite) differences of several mmag with other results. However, the Taylor-Joner values of (R-I)C data are supported at the 1mmag level. Using the (R-I)C data and other published results, an (R-I)C catalog is assembled for 146 Hyades stars with spectral types earlier than about K5. For single stars with multiple contributing data, the rms errors of the catalog entries are less than 4.4 mmag. Temperatures on the Di Benedetto angular-diameter scale are also given in the catalog and are used to help update published analyses of high-dispersion values of [Fe/H] for the Hyades. The best current mean Hyades value of [Fe/H] is found to be +0.103+/-0.008dex and is essentially unchanged from its previous value. In addition to these numerical results, recommendations are made about improving attitudes and practices that are pertinent to issues like those raised by Pinsonneault et al.
3706. TEMP. V. Photometry of HAT-P-9, HAT-P-32 & HAT-P-36
ID:
ivo://CDS.VizieR/J/AJ/157/82
Title:
TEMP. V. Photometry of HAT-P-9, HAT-P-32 & HAT-P-36
Short Name:
J/AJ/157/82
Date:
21 Oct 2021
Publisher:
CDS
Description:
During the past five years, 6, 7, and 26 transit observations were carried out for the HAT-P-9b, HAT-P-32b, and HAT-P-36b systems, respectively, through the Transiting Exoplanet Monitoring Project network. Combined with the published photometric data and radial-velocity measurements, our new photometry allows us to revisit the system parameters and search for additional close-in planetary companions in these hot Jupiter systems. We measure an updated R_P_/R_*_=0.1260+/-0.0011 for HAT-P-36 system in the R band, which is 4.5{sigma} larger than the published i-band radius ratio of 0.1186+/-0.0012. We also perform a transit timing variation (TTV) analysis for each system. Because no significant TTVs were found, we place an upper mass limit on an additional planet for each system.
3707. Tertiary companions to close spectroscopic binaries
ID:
ivo://CDS.VizieR/J/AJ/144/62
Title:
Tertiary companions to close spectroscopic binaries
Short Name:
J/AJ/144/62
Date:
21 Oct 2021
Publisher:
CDS
Description:
We report the first results of a multi-epoch search for wide (separations greater than a few tens of AU), low-mass tertiary companions of a volume-limited sample of 118 known spectroscopic binaries within 30pc of the Sun, using the Two Micron All Sky Survey Point Source Catalog and follow-up observations with the KPNO and CTIO 4m telescopes. Note that this sample is not volume complete but volume limited, and, thus, there is incompleteness in our reported companion rates. We are sensitive to common proper motion companions with separations from roughly 200AU to 10000AU (~10"-->~10'). From 77 sources followed-up to date, we recover 11 previously known tertiaries, 3 previously known candidate tertiaries, of which 2 are spectroscopically confirmed and 1 rejected, and 3 new candidates, of which 2 are confirmed and 1 rejected. This yields an estimated wide tertiary fraction of 19.5^+5.2^_-3.7_%. This observed fraction is consistent with predictions set out in star formation simulations where the fraction of wide, low-mass companions to spectroscopic binaries is >10%.
3708. TESS Input Catalog version 8.2 (TIC v8.2)
ID:
ivo://CDS.VizieR/IV/39
Title:
TESS Input Catalog version 8.2 (TIC v8.2)
Short Name:
IV/39
Date:
03 Mar 2022 07:19:26
Publisher:
CDS
Description:
We define various types of "phantom" stars that may appear in the TESS Input Catalog (TIC), and provide examples and lists of currently known cases. We present a methodology that can be used to check for phantoms around any object of interest in the TIC, and we present an approach for correcting the TIC-reported flux contamination factors accordingly. We checked all 2077 TESS Objects of Interest (TOIs) known as of July 21st 2020 (Sectors 1 to 24) and sent corrections for 291 stars to MAST where they are integrated into the publicly available TIC-8, updating it to TIC 8.1. We used the experience gained to construct an all-sky algorithm searching for "phantoms" which led to 34 million updates integrated into TIC 8.2.
3709. TESS Input Catalog - v8.0 (TIC-8)
ID:
ivo://CDS.VizieR/IV/38
Title:
TESS Input Catalog - v8.0 (TIC-8)
Short Name:
IV/38
Date:
11 Feb 2022 14:26:27
Publisher:
CDS
Description:
The TIC is used to help identify two-minute cadence target selection for the Transiting Exoplanet Survey Satellite (TESS) mission, and to calculate physical and observational properties of planet candidates. It is for use by both the TESS science team and the public, and it is periodically updated - the current version is TIC-8. TIC-8 uses the GAIA DR2 catalog as a base and merges a large number of other photometric catalogs, including 2MASS, UCAC4, APASS, SDSS, WISE, etc. There are roughly 1.5 billion stellar and extended sources in TIC-8, containing compiled magnitudes including B, V, u, g, r, i, z, J, H, K, W1-W4, and G. This version was released in May 2019, and is expected to be the last official version of the TIC produced by the TESS mission, although future, independent development of the TIC is possible. The TIC is the responsibility of the SAO Arm of the TESS Science Office under the leadership of David Latham. The TESS Target Selection Working Group (TSWG) is co-chaired by Keivan Stassun (Vanderbilt) & Joshua Pepper (Lehigh).
3710. TESS-Keck survey. VI. HIP-97166 radial velocity
ID:
ivo://CDS.VizieR/J/AJ/162/265
Title:
TESS-Keck survey. VI. HIP-97166 radial velocity
Short Name:
J/AJ/162/265
Date:
16 Mar 2022 06:42:57
Publisher:
CDS
Description:
We report the discovery of HIP-97166b (TOI-1255b), a transiting sub-Neptune on a 10.3day orbit around a K0 dwarf 68pc from Earth. This planet was identified in a systematic search of TESS Objects of Interest for planets with eccentric orbits, based on a mismatch between the observed transit duration and the expected duration for a circular orbit. We confirmed the planetary nature of HIP-97166b with ground-based radial-velocity measurements and measured a mass of M_b_=20{+/-}2M{Earth} along with a radius of R_b_=2.7{+/-}0.1R{Earth} from photometry. We detected an additional nontransiting planetary companion with M_c_sini=10{+/-}2M{Earth} on a 16.8day orbit. While the short transit duration of the inner planet initially suggested a high eccentricity, a joint RV-photometry analysis revealed a high impact parameter b=0.84{+/-}0.03 and a moderate eccentricity. Modeling the dynamics with the condition that the system remain stable over >10^5^ orbits yielded eccentricity constraints e_b_=0.16{+/-}0.03 and e_c_<0.25. The eccentricity we find for planet b is above average for the small population of sub-Neptunes with well-measured eccentricities. We explored the plausible formation pathways of this system, proposing an early instability and merger event to explain the high density of the inner planet at 5.3{+/-}0.9g/cc as well as its moderate eccentricity and proximity to a 5:3 mean-motion resonance.