- ID:
- ivo://CDS.VizieR/J/A+A/644/A104
- Title:
- Auriga bright stars BRITE phot. and RV
- Short Name:
- J/A+A/644/A104
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We aim to determine periods for bright stars in the Auriga field that are otherwise not easily accessible for ground-based photometry. Continuous photometry with up to three BRITE satellites was obtained for 12 targets and subjected to a period search. Contemporaneous high-resolution optical spectroscopy with STELLA was used to obtain radial velocities through cross correlation with template spectra as well as to determine astrophysical parameters through a comparison with model spectra.
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Search Results
- ID:
- ivo://CDS.VizieR/J/AJ/158/25
- Title:
- Automated triage and vetting of TESS candidates
- Short Name:
- J/AJ/158/25
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- NASA's Transiting Exoplanet Survey Satellite (TESS) presents us with an unprecedented volume of space-based photometric observations that must be analyzed in an efficient and unbiased manner. With at least ~1000000 new light curves generated every month from full-frame images alone, automated planet candidate identification has become an attractive alternative to human vetting. Here we present a deep learning model capable of performing triage and vetting on TESS candidates. Our model is modified from an existing neural network designed to automatically classify Kepler candidates, and is the first neural network to be trained and tested on real TESS data. In triage mode, our model can distinguish transit-like signals (planet candidates and eclipsing binaries) from stellar variability and instrumental noise with an average precision (the weighted mean of precisions over all classification thresholds) of 97.0% and an accuracy of 97.4%. In vetting mode, the model is trained to identify only planet candidates with the help of newly added scientific domain knowledge, and achieves an average precision of 69.3% and an accuracy of 97.8%. We apply our model on new data from Sector 6, and present 288 new signals that received the highest scores in triage and vetting and were also identified as planet candidates by human vetters. We also provide a homogeneously classified set of TESS candidates suitable for future training.
- ID:
- ivo://CDS.VizieR/J/AJ/158/58
- Title:
- Autoregressive planet search for Kepler stars
- Short Name:
- J/AJ/158/58
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The 4 yr light curves of 156717 stars observed with NASA's Kepler mission are analyzed using the autoregressive planet search (ARPS) methodology described by Caceres et al. (2019AJ....158...57C). The three stages of processing are maximum-likelihood ARIMA modeling of the light curves to reduce stellar brightness variations, constructing the transit comb filter periodogram to identify transit-like periodic dips in the ARIMA residuals, and Random Forest classification trained on Kepler team confirmed planets using several dozen features from the analysis. Orbital periods between 0.2 and 100 days are examined. The result is a recovery of 76% of confirmed planets, 97% when period and transit depth constraints are added. The classifier is then applied to the full Kepler data set; 1004 previously noticed and 97 new stars have light-curve criteria consistent with the confirmed planets, after subjective vetting removes clear false alarms and false positive cases. The 97 Kepler ARPS candidate transits mostly have periods of P<10 days; many are ultrashort period hot planets with radii <1% of the host star. Extensive tabular and graphical output from the ARPS time series analysis is provided to assist in other research relating to the Kepler sample.
- ID:
- ivo://CDS.VizieR/J/AJ/116/2108
- Title:
- AWM 7 radial velocities
- Short Name:
- J/AJ/116/2108
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have measured redshifts and Kron-Cousins R-band magnitudes for a sample of galaxies in the poor cluster AWM 7. We have measured redshifts for 172 galaxies; 106 of these are cluster members. We determine the luminosity function (LF) from a photometric survey of the central 1.2x1.2h^-1^Mpc. The LF has a bump at the bright end and a faint-end slope of {alpha}=-1.37+/-0.16, populated almost exclusively by absorption-line galaxies. The cluster velocity dispersion is lower in the core (~530km/s) than at the outskirts (~680km/s), consistent with the cooling flow seen in the X-ray. The cold core extends ~150h^-1^kpc from the cluster center. The Kron-Cousins R-band mass-to-light ratio of the system is 650+/-170hM_{sun}_/L_{sun}_, substantially lower than previous optical determinations, but consistent with most previous X-ray determinations. We adopt H_0_=100hkm/s/Mpc throughout this paper; at the mean cluster redshift (5247+/-76km/s), 1h^-1^Mpc subtends 65.5'.
- ID:
- ivo://CDS.VizieR/J/AJ/131/2035
- Title:
- B and R magnitudes for spiral galaxies
- Short Name:
- J/AJ/131/2035
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- It is an observational fact that bulges of spiral galaxies contain a high fraction of old and metal-rich stars. Following this observational fact, we have investigated the colors of 21 bulges hosted by a selected sample of high surface brightness spiral galaxies and low surface brightness galaxies observed in the B and R optical bands and the J and Ks near-IR bands.
- ID:
- ivo://CDS.VizieR/J/A+A/321/L9
- Title:
- Barium stars in the HR diagram
- Short Name:
- J/A+A/321/L9
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Table2 is an extension of Table 1 to 15 additional stars with slightly less accurate parallaxes (see text). The entries are the same in both tables.
- ID:
- ivo://CDS.VizieR/J/A+AS/124/281
- Title:
- BH Vir BV light curves
- Short Name:
- J/A+AS/124/281
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Photoelectric observations of the short period eclipsing binary BH Vir in B and V bands are presented. Comparing with earlier published observations, we found that there were smaller variations in the light curve (outside eclipse) in 1991 than in the previous data.
- ID:
- ivo://CDS.VizieR/J/AJ/159/15
- Title:
- Binary stars in Upper Scorpius
- Short Name:
- J/AJ/159/15
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- To address the statistics of binary stars in the 8 Myr old Upper Scorpius (USco) star formation region, we conducted a speckle interferometric survey of 614 association members more massive than 0.4 M_{sun}_ (spectral types earlier than M3V) based on the list of Luhman et al. (2018, J/AJ/156/271). We resolved 187 pairs, 55 of which are new discoveries. Also using the published data and the Gaia DR2 (Cat. I/345), a catalog of 250 physical binaries was produced. We carefully estimated detection limits for each target and studied binary statistics in the separation range from 0.06" to 20" (9-2800 au), as well as clustering at larger separations. The frequency of companions with mass ratios q>0.3 in this separation range is 0.33+/-0.04 and 0.35+/-0.04 for early M- and solar-type stars, respectively, larger by 1.62+/-0.22 and 1.39+/-0.18 times compared to field stars of similar masses. The excess is produced mostly by pairs closer than 100 au. At separations from 100 to 10^4^ au, the separation distribution and companion fraction resemble those of solar-type stars in the field. However, unlike in the field, we see a relative deficit of equal-mass binaries at separations of ~500 au, compared to smaller and larger separations. The distribution of q depends on the separation, with a preference of larger q and a larger fraction of twins with q>0.95 at smaller separations. The binary population of USco differs from binaries in the field in several ways and suggests that binary statistics is not universal.
- ID:
- ivo://CDS.VizieR/J/A+A/587/A61
- Title:
- BlackCAT, stellar-mass BH in X-ray trans.
- Short Name:
- J/A+A/587/A61
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- During the last ~50 years, the population of black hole candidates in X-ray binaries has increased considerably, with 59 Galactic objects being detected in transient low-mass X-ray binaries, as well as a few in persistent systems (including ~5 extragalactic binaries). We collect near-infrared, optical, and X-ray information spread over hundreds of references to study the population of black holes in X-ray transients as a whole. We present the most updated catalogue of black hole transients. This contains X-ray, optical, and near-infrared observations, together with their astrometric and dynamical properties. The catalogue provides new and useful information in both statistical and observational parameters and provides a thorough and complete overview of the black hole population in the Milky Way. Analysing the distances and spatial distribution of the observed systems, we estimate a total population of ~1300 Galactic black hole transients. This means that we have only discovered less than ~5% of the total Galactic distribution. The complete version of this catalogue will be continuously updated online and in the Virtual Observatory, including finding charts and data in other wavelengths.
- ID:
- ivo://CDS.VizieR/I/228
- Title:
- Bordeaux AC Zone Data Reduced to ACRS
- Short Name:
- I/228
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The U.S. Naval Observatory is in the process of making new reductions of the Astrographic Catalogue (AC) using a modern reference system, the ACRS, which represents the system of the FK5. The data from the Bordeaux Zone, whose plates are centered between declinations +11 and +17 degrees (eq. 1900), have been analyzed for scale, rotation, tilt, coma, magnitude equation, radial distortion and distortions introduced by the use of reseaux in the Carte du Ciel program. The result is a positional catalog of over 223,000 stars on eq. J2000.0, epoch of observation. Additionally, all stars have been matched with the Tycho Input Catalog (revised); those numbers have been added for additional identification purposes.
