- ID:
- ivo://CDS.VizieR/J/MNRAS/421/181
- Title:
- EC 01541-1409 pulsations frequencies
- Short Name:
- J/MNRAS/421/181
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present follow-up observations of the pulsating subdwarf B (sdB) star EC 01541-1409 as part of our efforts to resolve pulsation spectra for use in asteroseismological analyses. This paper reports on data obtained from a single-site campaign, during 2008, and a multisite campaign, during 2009. From limited 2008 data, we were able to clearly resolve and pre-whiten 24 periods. A subsequent multisite campaign spanning nearly 2 months found over 30 individual periodicities most of which were unstable in amplitude and/or phase. Pulsation amplitudes were found to the detection limit, meaning that further observations would likely reveal more periodicities.
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- ID:
- ivo://CDS.VizieR/J/other/JAD/25.1
- Title:
- EE Cam, FG Vir and 44 Tau light curves
- Short Name:
- J/other/JAD/25.1
- Date:
- 22 Feb 2022
- Publisher:
- CDS
- Description:
- The three delta Scuti pulsators EE Cam, FG Vir and 44 Tau are of special interest because their pulsation properties are different from those expected from the low rotational velocities indicated by spectroscopic measurements. This paper presents the previously unpublished high-precision photometric data obtained by the Delta Scuti Network during 780 nights.
- ID:
- ivo://CDS.VizieR/J/MNRAS/386/2039
- Title:
- Elemental abundances of {alpha} Cir
- Short Name:
- J/MNRAS/386/2039
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have used the Sydney University Stellar Interferometer to measure the angular diameter of alpha Cir. This is the first detailed interferometric study of a rapidly oscillating A (roAp) star, alpha Cir being the brightest member of its class. We used the new and more accurate Hipparcos parallax to determine the radius to be 1.967+/-0.066R_{sun}_. We have constrained the bolometric flux from calibrated spectra to determine an effective temperature of 7420+/-170K . This is the first direct determination of the temperature of an roAp star. Our temperature is at the low end of previous estimates, which span over 1000K and were based on either photometric indices or spectroscopic methods. In addition, we have analysed two high-quality spectra of alpha Cir, obtained at different rotational phases and we find evidence for the presence of spots.
- ID:
- ivo://CDS.VizieR/J/AJ/129/2815
- Title:
- Eleven new {gamma} Doradus variables
- Short Name:
- J/AJ/129/2815
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present new high-dispersion spectroscopic and precise photometric observations to identify 11 new {gamma} Doradus variables. Seven of these new Doradus stars appear to be single, three are primaries of single-lined binaries, and one has two distant visual companions; none are double-lined or close visual binaries. Several of the stars show spectroscopic line-profile and low-amplitude radial velocity variability indicative of pulsation. All 11 stars are photometrically variable with amplitudes between 8 and 93mmag in Johnson B and periods between 0.398 and 2.454 days.
- ID:
- ivo://CDS.VizieR/J/A+A/560/A69
- Title:
- Emission lines in a flare of AB Dor A
- Short Name:
- J/A+A/560/A69
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a identification catalog of chromospheric emission lines in the optical range for two flares on AB Dor A, with event 1 being larger than event 3. An additional flare event 2 is not described here because of its overlap with event 1. All lines are identified in an flare- only spectrum, i.e. with a quiescent spectrum subtracted. The data were obtained with ESO's Kueyen telescope equipped with the UVES spectrograph on November 25/26 in 2009. The instrument was operated in dichroic mode (spectral coverage from 3720 to 4945 and from 5695 to 9465 AA). We tabulate measured wavelength, line flux and FWHM for every line and also provide the rest wavelength from the Moore catalog which was used for identification (Moore, 1972, Nat. Stand. Ref. Data. Ser., 40). Few lines were identified with the NIST database.
- ID:
- ivo://CDS.VizieR/J/A+A/419/215
- Title:
- Emission lines of Sr filament near {eta} Car
- Short Name:
- J/A+A/419/215
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have obtained deep spectra from 1640 to 10100{AA} with the Space Telescope Imaging Spectrograph (STIS) of the strontium filament, a largely neutral emission nebulosity lying close to the very luminous star Eta Carinae and showing an uncommon spectrum. Over 600 emission lines, both permitted and forbidden, have been identified.
- ID:
- ivo://CDS.VizieR/J/A+A/371/579
- Title:
- Empirical relations for cluster RR Lyrae
- Short Name:
- J/A+A/371/579
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Our former study on the empirical relations between the Fourier parameters of the light curves of the fundamental mode RR Lyrae stars and their basic stellar parameters has been extended to considerably larger data sets. The most significant contribution to the absolute magnitude M_V_ comes from the period P and from the first Fourier amplitude A_1_, but there are statistically significant contributions also from additional higher order components, most importantly from A_3_ and in a lesser degree from the Fourier phase phi_51_. When different colors are combined in reddening-free quantities, we obtain basically period-luminosity-color relations. From the standard deviations of the various regressions, an upper limit can be obtained on the overall inhomogeneity of the reddening in the individual clusters. This yields {sigma}_E(B-V)_<0.012mag, which also implies an average minimum observational error of {sigma}_V_>0.018mag.
- ID:
- ivo://CDS.VizieR/J/A+A/566/A43
- Title:
- EPOCH Project. EROS-2 LMC periodic variables
- Short Name:
- J/A+A/566/A43
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The EPOCH (EROS-2 periodic variable star classification using machine learning) project aims to detect periodic variable stars in the EROS-2 light curve database. In order to classify these variables, we first build a training set by compiling known variables in the Large Magellanic Could area from the OGLE and MACHO surveys. We crossmatch these variables with the EROS-2 sources and extract 22 variability features from 28,392 light curves of the corresponding EROS-2 sources. We then use Random Forests to classify the EROS-2 sources in the training set. We design the model to separate not only Delta Scuti stars, RR Lyraes, Cepheids, eclipsing binaries and long-period variables, the "superclasses", but also their subclasses, such as RRab, RRc, RRd and RRe for RR Lyraes, and similarly for the other variable types. We apply the trained model to the entire EROS-2 LMC database containing about 29 million sources and find 117,234 periodic variable candidates. Out of these 117,234 periodic variables, 55,285 have not been discovered by either OGLE or MACHO variability studies. This set comprises 1906 Delta Scuti stars, 6,607 RR Lyraes, 638 Cepheids, 178 Type II Cepheids, 34,562 eclipsing binaries and 11,394 long-period variables.
- ID:
- ivo://CDS.VizieR/J/A+A/622/A190
- Title:
- eps Tau intensity and RV time-series data
- Short Name:
- J/A+A/622/A190
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Asteroseismic analysis of solar-like stars allows us to determine physical parameters such as stellar mass, with a higher precision compared to most other methods. Even in a well-studied cluster such as the Hyades, the masses of the red giant stars are not well known, and previous mass estimates are based on model calculations (isochrones). The four known red giants in the Hyades are assumed to be clump (core-helium-burning) stars based on their positions in colour-magnitude diagrams, however asteroseismology offers an opportunity to test this assumption. Using asteroseismic techniques combined with other methods, we aim to derive physical parameters and the evolutionary stage for the planet hosting star epsilon Tau, which is one of the four red giants located in the Hyades. We analysed time-series data from both ground and space to perform the asteroseismic analysis. By combining high signal-to-noise (S/N) radial-velocity data from the ground-based SONG network with continuous space-based data from the revised Kepler mission K2, we derive and characterize 27 individual oscillation modes for epsilon Tau, along with global oscillation parameters such as the large frequency separation {Delta}{nu} and the ratio between the amplitude of the oscillations measured in radial velocity and intensity as a function of frequency. The latter has been measured previously for only two stars, the Sun and Procyon. Combining the seismic analysis with interferometric and spectroscopic measurements, we derive physical parameters for epsilon Tau, and discuss its evolutionary status. Along with other physical parameters, we derive an asteroseismic mass for epsilon Tau of M=2.458+/-0.073M_{sun}_, which is slightly lower than previous estimates, and which leads to a revised minimum mass of the planetary companion. Noting that the SONG and K2 data are non-simultaneous, we estimate the amplitude ratio between intensity and radial velocity to be 42.2+/-2.3ppm m/s, which is higher than expected from scaling relations.
- ID:
- ivo://CDS.VizieR/J/ApJ/416/276
- Title:
- Eq. of State in Magnetic Neutron Stars
- Short Name:
- J/ApJ/416/276
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This catalog is based on the calculated equation of state in cold dense matter. Each table in the catalog lists bulk properties of Fe-56 in a magnetic field ranging from one million to 1000 million Tesla.
