Related papers: Characterizing bright $\delta$ Scuti pulsators usi…
We report on a multi-site photometric campaign on the high-amplitude $\delta$ Scuti star V2367 Cyg in order to determine the pulsation modes. We also used high-dispersion spectroscopy to estimate the stellar parameters and projected…
The light curves of 2768 stars with effective temperatures and surface gravities placing them near the gamma Doradus/delta Scuti instability region were observed as part of the Kepler Guest Observer program from Cycles 1 through 5. The…
As part of the NASA Kepler Guest Observer program, we requested and obtained long-cadence data on about 2700 faint (magnitude 14-16) Kepler stars with effective temperatures and surface gravities that lie near or within the pulsation…
TESS observations of pulsating hot main sequence stars paint a very different picture from what is currently accepted. There are large numbers of delta Scuti (DSCT) stars hotter than the theoretical hot edge of the instability strip,…
We have explored a sample of suspected A-type binaries in a systematic way, both spectroscopically and photometrically. Due to their location in the H-R diagram, indications of pulsation and/or chemical peculiarities among these suspected…
Eclipsing binaries (EBs) are unique targets for measuring precise stellar properties and constrain stellar evolution models. In particular, it is possible to measure at the percent level masses and radii of both components of a double-lined…
We present BVR observations and low-resolution spectra collected by the Kottamia Astronomical Observatory 1.88 m telescope (KAO) for the new pulsating star ASAS J063309+1810.8 (hereafter it will be called ASAS06+18). The photometric…
Searching for main-sequence pulsators, we analyzed photometry of ~200,000 variable star candidates from the OGLE-II Galactic fields, finding 193 high-amplitude Delta Scuti stars. This doubles the number of known stars of this type. The…
We use four years of Kepler photometry to study the non-eclipsing spectroscopic binary KIC 10080943. We find both components to be $\gamma$ Doradus/$\delta$ Scuti hybrids, which pulsate in both p and g modes. We present an analysis of the g…
Only a fraction of the theoretically predicted nonradial pulsation modes have so far been observed in Delta Scuti stars. Nevertheless, the large number of frequencies detected in recent photometric studies of selected Delta Scuti stars…
About 766 $\delta$ Scuti stars were observed by LAMOST by June 16, 2017. Stellar atmospheric parameters of 525 variables were determined, while spectral types were obtained for all samples. In the paper, those spectroscopic data are…
The group of lambda Bootis type stars comprises late B- to early F-type, Population I objects which are basically metal weak, in particular the Fe group elements, but with the clear exception of C, N, O and S. The present work is a…
Using TESS 20-sec cadence data, we have discovered an unusual combination of pulsating stars in what we infer to be a binary system. The binary consists of a standard $\delta$ Scuti star with pulsations over the range 32-41 d$^{-1}$; this…
The first in-depth photometric study of four Delta Scuti stars was performed. We used time series data from the Transiting Exoplanet Survey Satellite (TESS) that is available in different sectors. According to the extracted maxima from TESS…
The evolutionary stage of the delta Scuti star 44 Tau has been unclear. Recent asteroseismic studies have claimed models on the main sequence, as well as in the expansion phase of the post-main sequence evolution. However, these models…
We concentrate on an asteroseismological study of HD 261711, a rather hot delta Scuti type pulsating member of the young open cluster NGC 2264 located at the blue border of the instability region. HD 261711 was discovered to be a pre-main…
In the last years, space missions such as COROT, Kepler or MOST have provided very accurate photometric observational data. In the particular case of $\delta$ Scuti stars, the observed frequency spectra have hundreds (if not thousands) of…
CoRoT ID 105733033 is an excellent example of hybrid pulsators as it shows g- and p-modes with almost similar amplitudes in two clearly distinct frequency domains. Classical Fourier analysis allows the dectection of frequencies with an…
Investigating chemically peculiar pulsating stars is crucial for understanding the pulsation driving mechanism in detail. To reveal the true peculiarity properties of stars detailed spectroscopic analysis is essential. Therefore, in this…
Delta Scuti ($\delta$ Sct) variables are intermediate mass stars that lie at the intersection of the main sequence and the instability strip on the Hertzsprung-Russel diagram. Various lines of evidence indicate that nonlinear mode…