Related papers: Pulsation of the Lambda Bootis star HD 210111
In this study, pulsational and physical characteristics of two $\delta$ Scuti stars, V775 Tau and V483 Tau, are analysed by using four-year high-precision photometric data of STEREO satellite. Thus, it is aimed to gain new insights into…
The searches for transiting exoplanets have produced a vast amount of time-resolved photometric data of many millions of stars. One of the leading ground-based surveys is the SuperWASP project. We present the initial results of a survey of…
Tidally tilted pulsators (TTPs) are an intriguing new class of oscillating stars in binary systems; in such stars, the pulsation axis coincides with the line of apsides, or semi-major axis, of the binary. All three TTPs discovered so far…
We present new spectroscopic and photometric time series observations of the delta Scuti star FG~Vir. We detect the oscillations via changes in the equivalent widths of hydrogen and metal absorption lines. From the ratios between…
Based on the LAMOST spectroscopy and TESS time-series photometry, we have obtained a main-sequence star sample of $\delta$ Scuti and $\gamma$ Doradus stars. The sample includes 1534 $\delta$ Sct stars, 367 $\gamma$ Dor stars, 1703 $\delta$…
Using high-cadence observations from the Zwicky Transient Facility at low Galactic latitudes, we have discovered a new class of pulsating, hot, compact stars. We have found four candidates, exhibiting blue colors ($g-r\leq-0.1$ mag),…
We report the frequency analysis of a known roAp star, HD 86181 (TIC 469246567), with new inferences from TESS data. We derive the rotation frequency to be $\nu_{rot}$ = 0.48753 $\pm$ 0.00001d$^{-1}$. The pulsation frequency spectrum is…
Observing Delta Scuti stars is most important as their multi-frequency spectrum of radial pulsations provide strong constraints on the physics of the stars interior; so any new detection and observation of these stars is a valuable…
Using V images taken in May and June 2012 with the SARA Consortium's 0.9-meter telescope located at Kitt Peak National Observatory, we searched for variable stars in the globular cluster M107 (NGC 6171). The search was accomplished using…
The nature of period and amplitude changes in nonradial pulsators is presently unknown. It is therefore important to examine the correlations between these changes in stars with a large number of simultaneously excited pulsation modes.…
We present a study of bright, young $\delta$ Scuti stars near the zero-age main sequence using TESS light curves and Gaia DR3 data. From a sample of 2041 stars with G<7 and $G_{BP}-G_{RP}$ colour in the range 0-0.6, we identified 444…
We present time series observations of intermediate mass PMS stars belonging to the young star cluster IC 348. The new data reveal that a young member of the cluster, H254, undergoes periodic light variations with delta Scuti-like…
Based on 2-minute cadence TESS data from sectors 1-50, we report the results of the systematic extraction of $\delta$ Scuti-type pulsations in the 6431 eclipsing binaries with orbital periods shorter than 13 days. A total number of 242…
We present a preliminary abundance analysis of the isolated Herbig Ae star PDS2 (CD -53 251, 2MASS J01174349-5233307). Our adopted model has Teff = 6500K, log(g) = 3.5. It is likely that PDS2 belongs to the class of young stars with…
It is still a matter of debate if the group of lambda Bootis stars is homogeneously defined. A widely discussed working hypothesis formulates that two apparent solar abundant stars of an undetected spectroscopic binary system mimic a single…
We present the first asteroseismic results for $\delta$ Scuti and $\gamma$ Doradus stars observed in Sectors 1 and 2 of the TESS mission. We utilise the 2-min cadence TESS data for a sample of 117 stars to classify their behaviour regarding…
The NASA Kepler spacecraft data revealed a large number of multimode nonradially pulsating gamma Dor and delta Sct variable star candidates. The high precision long time-series photometry makes it possible to study amplitude variations of…
We have studied over 1600 Am stars at a photometric precision of 1 mmag with SuperWASP photometric data. Contrary to previous belief, we find that around 200 Am stars are pulsating delta Sct and gamma Dor stars, with low amplitudes that…
We analysed ASAS-3 photometry of bright early-type stars with the goal of finding new Beta Cephei stars. We were particularly interested in stars that would be good for seismic analysis, i.e., stars that (i) have a large number of excited…
We present an investigation of three chemically peculiar (CP) stars and one CP star candidate which exhibit photometric periods below 12 hours. New spectroscopic observations have been acquired which confirm the peculiar nature of all…