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تسجيل مستخدم جديدRotating Solar Models with Low Metal Abundances as Good as Those with High Metal Abundances
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Wuming Yang
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Standard solar models (SSM) constructed in accord with low metal abundances disagree with the seismically inferred results. We constructed rotating solar models with low metal abundances that included enhanced settling and convection overshoot. In one of our rotating models, textbf{AGSSr2a}, the convection overshoot allowed us to recover the radius of the base of convection zone (CZ) at a level of $1sigma$. The rotational mixing almost completely counteracts the enhanced settling for the surface helium abundance, but only partially for the surface heavy-element abundance. At the level of $1sigma$, the combination of rotation and enhanced settling brings the surface helium abundance into agreement with the seismically inferred value of $0.2485pm0.0035$, and makes the model have better sound-speed and density profiles than SSM constructed in accordance with high metal abundances. The radius of the base of the CZ and the surface helium abundance of textbf{AGSSr2a} are $0.713$ $R_{odot}$ and $0.2472$, respectively; the absolute values of the relative differences in sound speed and density between it and the Sun are less than $0.0025$ and $0.015$, respectively. Moreover, predicted neutrino fluxes of our model are comparable with the predictions of previous research works.
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