Matteo Cantiello edited Abstract.tex  about 10 years ago

Commit id: 4ef7e110d5357a7ddd80dcbf00411a904ff2ea9a

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Stars are born rotating. Observations during the main sequence reveal that the majority of objects with mass above $\sim $\approx  1.5\mso$ are spinning fairly rapidly. From the zero age main sequence to the final compact remnant, calculations including mechanisms for the transport of angular momentum can make predictions about the evolution of the internal angular momentum distribution. Thanks to asteroseismology and in particular to the KEPLER satellite it is now possible to test these predictions, since the splitting of mixed modes allows to measure the core rotation in red giants and clump stars. Here we calculate state-of-the-art stellar evolution models of rotating low-mass stars in the mass range $1.5-3.0 \mso$ from their zero age main sequence to the cooling white dwarf stage. These models include transport of angular momentum due to rotational mixing and magnetic fields in radiative zones (generated by the Tayler-Spruit dynamo). These models fail to predict the asteroseismic observations of stars on the RGB and during core He burning, implying that some extra angular momentum process must be operating on the early RGB of low mass stars. %To test such predictions, rotational periods can be observed, providing a direct constraint of the surface rotation rate. %Moreover the efficiency of internal transport mechanisms can sometimes be inferred by using indirect proxies, for example %the change in the surface abundances of certain isotopes. This is because the same instabilities and/or circulations %believed to be responsible for the angular momentum transport can also displace chemicals in the radial direction. %Recently it has also become possible to directly probe the rotation profile of stars other than the Sun. This is thanks %to asteroseismology: using the splitting of mixed modes it is possible to measure the degree of differential rotation %between core and envelope. Here we calculate state-of-the-art stellar evolution models of rotating low-mass stars in the %mass range $1.5-3.0 \mso$ from their zero age main sequence to the cooling white dwarf stage. These models include %transport of angular momentum due to rotational mixing and magnetic fields in radiative zones (generated by the Spruit-%Tayler dynamo). We show how the predictions of these calculations compare to the available observational constraints, %with a particular emphasis on the asteroseismic information coming from KEPLER observations of red giant stars.