The eclipsing binary star RS Sct is a semi-detached system of theβLyrae type.This system was photometered for six nights in 2019 August,and 2020 June and August.The light and radial velocity curves were simultaneousl...The eclipsing binary star RS Sct is a semi-detached system of theβLyrae type.This system was photometered for six nights in 2019 August,and 2020 June and August.The light and radial velocity curves were simultaneously analyzed to obtain the absolute physical and orbital parameters of the system,and the system geometry was determined.In this system,the primary component has filled its inner Roche lobe and the secondary component is close to filling it.Moreover,the change in the orbital period of this system was investigated.The presence of the third or fourth components and the mass transfer between the two components affect the orbital period of the system.In addition,the pulsation of the primary component was detected.Also,several frequencies with high signal-to-noise ratios were identified.According to the position of the primary component in the H-R diagram and the value of the obtained frequencies,this component is likely a delta-Scuti pulsator.展开更多
This paper deals with the numerical solution of initial value problems for pantograph differential equations with variable delays. We investigate the stability of one leg θ-methods in the numerical solution of these ...This paper deals with the numerical solution of initial value problems for pantograph differential equations with variable delays. We investigate the stability of one leg θ-methods in the numerical solution of these problems. Sufficient conditions for the asymptotic stability of θ-methods are given by Fourier analysis and Ergodic theory.展开更多
基金financial support of University of Birjand for this research under contract number 1399/D/6211。
文摘The eclipsing binary star RS Sct is a semi-detached system of theβLyrae type.This system was photometered for six nights in 2019 August,and 2020 June and August.The light and radial velocity curves were simultaneously analyzed to obtain the absolute physical and orbital parameters of the system,and the system geometry was determined.In this system,the primary component has filled its inner Roche lobe and the secondary component is close to filling it.Moreover,the change in the orbital period of this system was investigated.The presence of the third or fourth components and the mass transfer between the two components affect the orbital period of the system.In addition,the pulsation of the primary component was detected.Also,several frequencies with high signal-to-noise ratios were identified.According to the position of the primary component in the H-R diagram and the value of the obtained frequencies,this component is likely a delta-Scuti pulsator.
文摘This paper deals with the numerical solution of initial value problems for pantograph differential equations with variable delays. We investigate the stability of one leg θ-methods in the numerical solution of these problems. Sufficient conditions for the asymptotic stability of θ-methods are given by Fourier analysis and Ergodic theory.
