- ID:
- ivo://CDS.VizieR/J/AJ/142/39
- Title:
- Sample of 114 {gamma} Doradus candidates
- Short Name:
- J/AJ/142/39
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have carried out a photometric survey of a complete, volume-limited sample of {gamma} Doradus candidates. The sample was extracted from the Hipparcos catalog and consists of 114 stars with colors and absolute magnitudes within the range of known {gamma} Doradus stars and that also lie within a specified volume of 266600pc^3^. We devoted one year of observing time with our T12 0.8m automatic photometric telescope to acquire nightly observations of the complete sample of stars. From these survey observations, we identify 37 stars with intrinsic variability of 0.002mag or more. Of these 37 variables, 8 have already been confirmed as {gamma} Doradus stars in our earlier papers; we scheduled the remaining 29 variables on our T3 0.4m automatic telescope to acquire more intensive observations over the next two years. As promising new {gamma} Doradus candidates were identified from the photometry, we obtained complementary spectroscopic observations of each candidate with the Kitt Peak coude feed telescope. Analysis of our new photometric and spectroscopic data reveals 15 new {gamma} Doradus variables (and confirms two others), 8 new {delta} Scuti variables (and confirms one other), and 3 new variables with unresolved periodicity. Therefore, of the 114 {gamma} Doradus candidates in our volume-limited sample, we find 25 stars that are new or previously known {gamma} Doradus variables. This results in an incidence of 22% for {gamma} Doradus variability among candidate field stars for this volume of the solar neighborhood. The corresponding space density of {gamma} Doradus stars in this volume of space is 0.094 stars per 103pc^3^ or 94 stars per 106pc^3^. We provide an updated list of 86 bright, confirmed, {gamma} Doradus field stars.
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Search Results
1222. S10947 Aql photometry
- ID:
- ivo://CDS.VizieR/J/A+A/361/1005
- Title:
- S10947 Aql photometry
- Short Name:
- J/A+A/361/1005
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In the paper we report the discovery of a new variable star, called S10947 Aql, as the likely optical counterpart of RX J2009.8+1557. The optical variability pattern as well as the detected X-ray emission suggest that it is a chromospherically active binary of the RS Canum Venaticorum type. We discovered an occasional disappearance of the eclipsing minima as well as large variations in the eclipse amplitude. The present file contains the full set of measurements from the various types of the 705 photographic plates used in this investigation (note that the number of 709 given in the paper is wrong). The table file is sorted according to plate type which is listed in the first column. Given for each measurement are the Julian Date (corresponding to the time of mid-exposure) and the photographic magnitude. Uncertain measurements and/or upper limits are marked with a flag (4th column).
1223. S Arae photometry
- ID:
- ivo://CDS.VizieR/J/A+A/516/L15
- Title:
- S Arae photometry
- Short Name:
- J/A+A/516/L15
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In the context of long and continuous time-series photometry and after the MOST, CoRoT, KEPLER space missions and large geographic longitude ground-based networks, a new method is offered by the polar location helping to cope with the problem associated with the Earth's day-night cycle. We present the first long time-series photometry from Dome Charlie in the heart of Antarctica and analyze ~4400 photometric measurements of RR Lyrae star S Arae obtained in July and August 2007.
- ID:
- ivo://CDS.VizieR/J/A+A/341/818
- Title:
- s-Cepheid velocity curves
- Short Name:
- J/A+A/341/818
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The light curves of the first overtone Pop. I Cepheids (s-Cepheids) show a discontinuity in their {phi}_21_ vs. P diagram, near P=3.2day. This feature, commonly attributed to the 2:1 resonance between the first and the fourth overtones ({omega}_4_~2{omega}_1_), is not reproduced by the hydrodynamical models. With the goal of reexamining the resonance hypothesis, we have obtained new CORAVEL radial velocity curves for 14 overtone Cepheids. Together with 10 objects of Krzyt et al. (1999, in prep.), the combined sample covers the whole range of overtone Cepheid periods. The velocity Fourier parameters display a strong characteristic resonant behavior. In striking contrast to photometric ones, they vary smoothly with the pulsation period and show no jump at 3.2day. The existing radiative hydrodynamical models match the velocity parameters very well. The center of the {omega}_4_=2{omega}_1_ resonance is estimated to occur at Pr=4.58+/-0.04day, i.e. at a period considerably longer than previously assumed (3.2day). We identify two new members of the s-Cepheid group: MY Pup and V440 Per.
- ID:
- ivo://CDS.VizieR/J/MNRAS/363/734
- Title:
- Sculptor dSph variables metal abundances
- Short Name:
- J/MNRAS/363/734
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Low-resolution spectroscopy obtained with FORS2 at the Very Large Telescope (VLT) has been used for the measurement of individual metal abundances ([Fe/H]) for 110 variable stars, including 107 RR Lyrae stars and one anomalous Cepheid, and to trace the metal distribution of the oldest stellar component in the Sculptor dwarf spheroidal galaxy. The RR Lyrae stars are spread over a 15x15arcmin^2^ area around the galaxy centre.
1226. S Dor variables
- ID:
- ivo://CDS.VizieR/J/A+A/366/508
- Title:
- S Dor variables
- Short Name:
- J/A+A/366/508
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The goal in writing this paper is five fold: (1) to summarize the scientific achievements in the 20th century on S Dor variables (or LBVs); (2) to present an inventory of these variables in the Galaxy and the Magellanic Clouds with a description of their physical state and instability properties; (3) to emphasize the photometric achievements of the various types of instabilities. Generally this seems to be a neglected item resulting in a number of misunderstandings continuously wandering through literature; (4) to investigate the structure of the S Dor-area on the HR-diagram; (5) to estimate the total numbers of S Dor variables in the three stellar systems.
1227. SDSS new variables
- ID:
- ivo://CDS.VizieR/J/AJ/115/296
- Title:
- SDSS new variables
- Short Name:
- J/AJ/115/296
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The US Naval Observatory 0.2m Flagstaff Astrometric Scanning Transit Telescope (FASTT) was used to obtain astrometric information in 16 equatorial fields in support of the Sloan Digital Sky Survey (SDSS). Each field is approximately 7.6{deg}x3.2{deg} in size and was scanned ~10 times with overlapping CCD strip scans; star positions accurate to +/-50mas in each coordinate and magnitudes good to +/-0.011mag were determined. As an ancillary project, this database was searched for new variables, and the results of that search are presented here. Approximately 1500 new variables have been discovered, and accurate coordinates for ~100 previously identified variables and suspected variables are given.
- ID:
- ivo://CDS.VizieR/J/ApJS/145/245
- Title:
- SDSS stars in Draco dwarf spheroidal galaxy
- Short Name:
- J/ApJS/145/245
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Sloan Digital Sky Survey (SDSS, Stoughton et al., 2002AJ....123..485S) has scanned the entire region containing the Draco dwarf spheroidal galaxy to 23mag in g*. We present a catalog of stars found in a 453 arcmin^2^, elliptical region centered on the Draco dwarf spheroidal galaxy. Objects in the catalog are matched with five previously published catalogs. The catalog contains SDSS photometry for 5634 individual objects, and also the photometry from matches to any of the other catalogs. A comparison of the photometry between catalogs allows us to identify 142 candidate variable objects. One hundred and twelve of the suspected variables have colors consistent with RR Lyrae variables.
- ID:
- ivo://CDS.VizieR/J/AJ/134/973
- Title:
- SDSS Stripe 82 star catalogs
- Short Name:
- J/AJ/134/973
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We describe a standard star catalog constructed using multiple SDSS photometric observations (at least four per band, with a median of 10) in the ugriz system. The catalog includes 1.01 million nonvariable unresolved objects from the equatorial stripe 82 (|{delta}_J2000.0_|<1.266{deg}) in the right ascension range 20^h^34^m^-4^h^00^m^ and with the corresponding r-band (approximately Johnson V-band) magnitudes in the range 14-22. The distributions of measurements for individual sources demonstrate that the photometric pipeline correctly estimates random photometric errors, which are below 0.01mag for stars brighter than 19.5, 20.5, 20.5, 20, and 18.5 in ugriz, respectively (about twice as good as for individual SDSS runs). Several independent tests of the internal consistency suggest that the spatial variation of photometric zero points is not larger than ~0.01mag (rms). In addition to being the largest available data set with optical photometry internally consistent at the ~1% level, this catalog provides a practical definition of the SDSS photometric system. Using this catalog, we show that photometric zero points for SDSS observing runs can be calibrated within a nominal uncertainty of 2% even for data obtained through 1mag thick clouds, and we demonstrate the existence of He and H white dwarf sequences using photometric data alone. Based on the properties of this catalog, we conclude that upcoming large-scale optical surveys such as the Large Synoptic Survey Telescope will be capable of delivering robust 1% photometry for billions of sources.
- ID:
- ivo://CDS.VizieR/J/A+A/385/488
- Title:
- Search for duplicity in periodic Be stars
- Short Name:
- J/A+A/385/488
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Four Be stars, HR 1960, HR 2968, HR 3237 and HR 3642, selected according to their periodic variations in Hipparcos and Geneva photometries, have been monitored from 1998 until 2001 with the Coralie spectrograph. HR 1960 and HR 3237 are two new spectroscopic binaries, HR 3642 is a new lambda Eri star, and HR 2968 is stable.
