Related papers: Characterization of Kepler early-type targets
In this work we present the results of our analysis of 16,300 medium-resolution LAMOST spectra of late-type stars in the Kepler field with the aim of determining the stellar parameters, activity level, lithium atmospheric content, and…
Stellar fundamental parameters are important in the asteroseismic study of Kepler light curves. However, the most used estimates in the Kepler Input Catalog (KIC) are not accurate enough for hot stars. Using a sample of B stars from the…
During the last two years we have received long time-series photometric observations of bright (V mag < 8) main-sequence A- and B-type stars observed by the NASA TESS spacecraft and the Austria-Poland-Canada BRITE satellites. Using TESS…
Measuring phase modulation in pulsating stars has proved to be a highly successful way of finding binary systems. The class of pulsating main-sequence A and F variables known as delta Scuti stars are particularly good targets for this, and…
The physical properties of transiting exoplanets are connected with the physical properties of their host stars. We present a homogeneous spectroscopic analysis based on spectra of FGK-type stars observed with the Hydra spectrograph on the…
We conducted high dispersion spectroscopic observations of 50 superflare stars with Subaru/HDS. These 50 stars were selected from the solar-type superflare stars that we had discovered from the Kepler data. More than half (34 stars) of…
The subdwarf-B pulsator, KIC 10553698A, is one of 16 such objects observed with one-minute sampling for most of the duration of the Kepler Mission. Like most of these stars, it displays a rich g-mode pulsation spectrum with several clear…
With the dual aims of enlarging the list of extremely metal-poor stars identified in the Galaxy, and boosting the numbers of moderately metal-deficient stars in directions that sample the rotational properties of the thick disk, we have…
We have combined the Kepler Eclipsing Binary Catalogue with information from the HES, KIS and 2MASS photometric surveys to produce spectral energy distribution fits to over 2600 eclipsing binaries in the catalogue over a wavelength range of…
We present the discovery of nonradial pulsations in five hot subdwarf B (sdB) stars based on 27 days of nearly continuous time-series photometry using the Kepler spacecraft. We find that every sdB star cooler than $\approx 27\,500\,$K that…
HD4539 (alias PG0044+097 or EPIC220641886) is a bright (V=10.2) long-period V1093 Her-type subdwarf B (sdB) pulsating star that was observed by the Kepler spacecraft in its secondary (K2) mission. We use the K2 light curve (78.7 days) to…
The analysis of eclipsing binaries containing non-radial pulsators allows: i) to combine two different and independent sources of information on the internal structure and evolutionary status of the components, and ii) to study the effects…
During the primary Kepler mission, between 2009 and 2013, about 150,000 pre-selected targets were observed with a 29.42 minute-long cadence. However, a survey of background stars that fall within the field of view (FOV) of the downloaded…
Context. Thanks to the high-precision photometry from space missions such as Kepler and TESS, tidal perturbations and tilting of pulsations have been detected in more than a dozen binary systems. However, only two of these were g-mode…
We present a test for spin-orbit alignment for the host stars of 25 candidate planetary systems detected by the {\it Kepler} spacecraft. The inclination angle of each star's rotation axis was estimated from its rotation period, rotational…
In this series of two papers we present a high dispersion spectroscopic analysis of 8 candidate extremely metal poor stars selected from the Hamburg/ESO Survey and of 6 additional very metal poor stars. We demonstrate that with suitable…
The NASA space telescope Kepler has provided unprecedented time-series observations which have revolutionised the field of asteroseismology, i.e. the use of stellar oscillations to probe the interior of stars. The Kepler-data include…
The high precision data obtained by the {\it Kepler} satellite allows us to detect hybrid type pulsator candidates more accurately than the data obtained by ground-based observations. In this study, we present preliminary results on the new…
Context. Slowly pulsating B (SPB) stars are main-sequence multi-periodic oscillators that display non-radial gravity modes. For a fraction of these pulsators, 4-year photometric light curves obtained with the Kepler space telescope reveal…
(Abridged) Aims: Systematic surveys to search for exoplanets have been mostly dedicated to solar-type stars sofar. We developed in 2004 a method to extend such searches to earlier A-F type dwarfs and started spectroscopic surveys to search…