In the present work, we study correlations between stellar fundamental parameters and the oscillation amplitude for δ Scuti stars . We present this study for a sample of 17 selected δ Scuti stars belonging to 5 young open clusters. Taking advantage of properties of δ Scuti stars in clusters, we correct the photometric parameters of our objects for the effect of fast rotation. We confirm the ben...

Period changes of δ Scuti stars have been collected or redetermined from the available observations and are compared with values computed from evolutionary models with and without convective core overshooting. For the radial pulsators of Pop. I, the observations indicate (1/P) dP/dt values around 10 year with equal distribution between period increases and decreases. The evolutionary models, on...

We report here the results of a statistical analysis of 28 δ Scuti stars from five open clusters, α Persei, Pleiades, Hyades, Praesepe and Coma. These δ Scuti variables, most of which are on the main sequence, tend to show a positive correlation between oscillation amplitude and absolute luminosity. No correlation is found between amplitude and effective temperature .

Abstract. The potential of photometric methods for the identification of l, the degree of spherical surface harmonic of a pulsating star, is investigated with special emphasis on Strömgren photometry applied to δ Scuti and γ Dor variables. Limitations of actual model atmospheres when fine precision is required for the calculations of partial derivatives and integrals, which depend on limb darke...

An order-of-magnitude estimate for the incidence of high-amplitude δ Scuti-type variable stars (HADS) in the δ Scuti area of the H-R diagram is calculated. Using a model for the stellar distribution in the Milky Way, we calculate the number of stars that are expected to fall in the δ Scuti area of the H-R diagram within the magnitude range and sky coverage of the ROTSE Survey for Variables I (R...

Five nights photoelectric photometric observations through v and y bands confirm the pulsation of classical Am δ Scuti variable 60 Tau. Power spectrum of light curves shows multi-period pulsation behavior of 60 Tau and two pulsation modes f1=13.0364 and f2=11.8521 cycles per day are definitely identified. Classical Am star 60 Tau is a complicated pulsation δ Scuti variable. Considering the puls...

Within the context of a fractal paradigm that emphasizes nature’s well-stratified hierarchical organization, the δ Scuti class of variable stars is investigated for evidence of discrete cosmological self-similarity. Methods that were successfully applied to the RR Lyrae class of variable stars are used to identify Atomic Scale analogues of δ Scuti stars and their relevant range of energy levels...

We consider here a representative set of δ Scuti stars observed in the Praesepe cluster, thanks to recent efforts of multi-site networks. We show that the effect of rotation on the determination of fundamental parameters Mbol and Teff cannot be neglected when modelling fast rotators as δ Scuti stars. We propose a method to take this effect into account and gain some indication on the rotation r...

RZ Cas is an Algol-type partial eclipsing binary, the secondary component of which has filled its Roche lobe. Its visual magnitude is 6.18 and its period is 1.195 days. The most important characteristics of RZ Cas are period change (due to mass transfer) and anomalies in the primary minimum of its light curve (due to δ Scuti pulsations). In this paper, light curves of RZ Cas are obtained using ...