Related papers: GSC 03144-595, a new triple-mode HADS
We present the analysis of the variability of HD 170699, a COROT star showing the characteristics of a non evolutionary Delta Scuti star with high rotational velocity. There is a clear period of 10.45 c/d with 5.29 mmag amplitude in the y…
71 Tau was discovered to be a $\delta$ Scuti star by Horan (1979, AJ 84, 1770). To our knowledge no other photometry of this star has been published. 71 Tau is the second brightest X-ray source in the Hyades and has been shown to be…
Recent observations of $\delta$ Scuti stars find evidence of nonlinear three-mode coupling in their oscillation spectra. There are two types of three-mode coupling likely to be important in $\delta$ Scuti stars: (i) direct coupling, in…
We report the discovery of the first high-amplitude delta Scuti star in an eclipsing binary, which we have designated UNSW-V-500. The system is an Algol-type semi-detached eclipsing binary of maximum brightness V = 12.52 mag. A best-fitting…
The frequency of pressure (p) mode in $\delta$~Scuti stars can exceed the Nyquist limit of \textit{Kepler} long-cadence photometry. {These 'super-Nyquist frequencies' (SNFs) are observed as 'reflected' peaks at lower frequencies, i.e., they…
In this work we propose a preliminary seismic investigation of $\delta$ Scuti stars in the Pleiades cluster, focusing on potential diagnostics of convection and core-overshooting. Taking into account the effect of fast rotation in the…
Under the Nainital-Cape Survey, eight $\delta\,$Scuti type pulsators have been discovered with the pulsation periods in the range of several minutes to few hours. In order to understand these observed pulsational variabilities, we have…
In this paper, we present a detailed analysis of the light variation of KIC 5623923 using high-precision time-series data from the $Kepler$ mission. The analysis reveals this target is an eclipsing binary system with $\delta$ Scuti type…
HD 21190 is a known $\delta$ Scuti star showing Ap star characteristics and a variability period of 3.6 h discovered by the Hipparcos mission. Using Gaia DR1 data for an astrometric analysis, it was recently suggested that HD 21190 forms a…
We consider the high mode density reported in the delta Scuti star HD 50844 observed by CoRoT. Using simulations, we find that extracting frequencies down to a given false alarm probability by means of successive prewhitening leads to a…
We present the analysis of one week of single-site high-speed CCD photometric observations of the cool ZZ Ceti star HS 0507+0434B. Ten independent frequencies are detected in the star's light variations: one singlet and three nearly-equally…
We conducted a long-term optical photometric and spectroscopic monitoring of the strongly variable, accreting young sun-like star [KOS94] HA11, associated with the dark cloud Lynds 1340, that exhibited large amplitude (5-6 magnitudes in the…
We present the detailed analysis of a new hybrid (p- and g-mode) sdB pulsator, TIC441725813 (TYC 4427-1021-1), discovered and monitored by TESS over 670 days. The TESS light curves available for this star were analysed using prewhitening…
We present the results of a long-term monitoring campaign of the H\alpha line in a sample of bright OB-supergiants (O7.5-B9) that aims at detecting rotationally modulated changes potentially related to the existence of large-scale wind…
A new observational study of the Herbig Ae star VV Ser has been performed in order to detect and accurately measure pulsation frequencies in the $\delta$ Scuti range. As it belongs to the continuous field of view of the asteroseismological…
Two years of Kepler data of KIC 8054146 (delta Sct/gamma Dor hybrid) revealed 349 statistically significant frequencies between 0.54 and 191.36 c/d (6.3 microHz to 2.21 mHz). The 117 low frequencies cluster in specific frequency bands, but…
We present an analysis of three new pulsating subdwarf B stars discovered in the SuperWASP archive. Two of the stars, J1938+5609 and J0902-0720, are p-mode pulsators; J1938+5609 shows a pulsation at 231.62 d$^{-1}$ ($P=373$ s; 2681 $\mu$Hz)…
Previous studies of GD 244 revealed seven pulsation frequencies (two doublets and three single periods) in the light variations of the star. The data obtained at McDonald Observatory between 2003 and 2006, and our additional measurements in…
HD 144277 was previously discovered by MOST space photometry to be a young and hot delta Scuti star showing regular groups of pulsation frequencies. The first asteroseismic models required lower than solar metallicity to fit the observed…
The light curves of the two large amplitude variable stars, R Scuti and AC Herculis, display irregular pulsation cycles with 'periods' of 75 and 35 days, respectively. We review the evidence that the observed time-series are generated by…