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تسجيل مستخدم جديدOn the seismic scaling relations $Delta u - bar{rho}$ and $ u_{rm max}- u_{rm c}$
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Scaling relations between asteroseismic quantities and stellar parameters are essential tools for studying stellar structure and evolution. We will address two of them, namely, the relation between the large frequency separation ($Delta u$) and the mean density ($bar{rho}$) as well as the relation between the frequency of the maximum in the power spectrum of solar-like oscillations ($ u_{rm max}$) and the cut-off frequency ($ u_{rm c}$). For the first relation, we will consider the possible sources of uncertainties and explore them with the help of a grid of stellar models. For the second one, we will show that the basic physical picture is understood and that departure from the observed relation arises from the complexity of non-adiabatic processes involving time-dependent treatment of convection. This will be further discussed on the basis of a set of 3D hydrodynamical simulation of surface convection.
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Asteroseismology of stars that exhibit solar-like oscillations are enjoying a growing interest with the wealth of observational results obtained with the CoRoT and Kepler missions. In this framework, scaling laws between asteroseismic quantities and
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Julio E. Rodriguez-Martin
, Antonio Garcia Hernandez andn Juan Carlos Suarez
, Jose Ramon Rodon
2020
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The lithium abundances in a few percent of giants exceed the value predicted by the standard stellar evolution models, and the mechanisms of Li enhancement are still under debate. The Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST)
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