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تسجيل مستخدم جديدPrecise determination of stellar parameters of the ZZ Ceti and DAZ white dwarf GD 133 through asteroseismology
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An increasing number of white dwarf stars show atmospheric chemical composition polluted by heavy elements accreted from debris disk material. The existence of such debris disks strongly suggests the presence of one or more planet(s) whose gravitational interaction with rocky planetesimals is responsible for their disruption by tidal effect. The ZZ Ceti pulsator and polluted DAZ white dwarf GD 133 is a good candidate for searching for such a potential planet. We started in 2011 a photometric follow-up of its pulsations. As a result of this work in progress, we used the data gathered from 2011 to 2015 to make an asteroseismological analysis of GD 133, providing the star parameters from a best fit model with $M$/$M_{odot}$ = 0.630 $pm$ 0.002, $T_{rm eff}$ = 12400 K $pm$ 70 K, log($M_{rm He}/M$) = -2.00 $pm$ 0.02, log($M_{rm H}/M$) = -4.50 $pm$ 0.02 and determining a rotation period of $approx$ 7 days.
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The thermally pulsing phase on the asymptotic giant branch (TP-AGB) is the last nuclear burning phase experienced by most of low and intermediate mass stars. During this phase, the outer chemical stratification above the C/O core of the emerging whit
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Asteroseismology is a unique tool to explore the internal structure of stars through both observational and theoretical research. The internal structure of pulsating hydrogen shell white dwarfs (ZZ Ceti stars) detected by asteroseismology is regarded
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