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Estimating The Mean Linewidth And Lifetime of Solar-like Oscillations of Stars

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 نشر من قبل Wuming Yang
 تاريخ النشر 2018
  مجال البحث فيزياء
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 تأليف Wuming Yang




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textbf{Scaling formulas were} deduced to describe the relations between the fundamental stellar parameters and the mean textbf{linewidth and lifetime} of solar-like oscillations of stars. The mean textbf{linewidth and} lifetime of solar-like oscillations textbf{are dependent on the large frequency separation, the effective temperature, and the acoustic impedance ($rho c$) in the photosphere} of stars. The mean lifetime textbf{can be} approximate to the lifetime of the mode with $ usim u_{max}$. We compared the results of the scaling relations with the mean lifetimes of solar-like oscillations of stars observed by textit{Kepler} and textit{CoRoT}, which shows that the observed mean lifetimes are reproduced well by the scaling relations. The dependence of the mean lifetime on textbf{the} large frequency separation, the effective temperature, and the acoustic impedance of stars textbf{indicates} that lifetimes of solar-like oscillations rely on the mass and evolutionary phase of stars. Moreover, our calculations show that the mean lifetimes of $p$-modes of stars can be affected by metallicity abundances.



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