Matteo Cantiello edited Abstract.tex  almost 11 years ago

Commit id: 1f32e4dbbf970095f0fc41bf300de45be81d2173

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Stars are born with non-negligible amount of angular momentum. A common assumption is that they reach a state of quasi-solid rotation at the zero age main sequence.   From there on their evolution im   Low-mass stars evolve past the main sequence toward their red giant stage. In this phase the star experience  The prediction of the spins of the compact remnants is a fundamental goal of the theory of stellar evolution. Aims. Here, we confront the predictions for white dwarf spins from evolutionary models, including rotation with observational constraints. Methods. We perform stellar evolution calculations for stars in the mass range 1. . . 3 M⊙ , including the physics of rotation, from the zero age main sequence into the TP-AGB stage. We calculate two sets of model sequences, with and without inclusion of magnetic fields. From the final computed models of each sequence, we deduce the angular momenta and rotational velocities of the emerging white dwarfs. Results. While models including magnetic torques predict white dwarf rotational velocities between 2 and 10 km s−1 , those from the nonmagnetic sequences are found to be one to two orders of magnitude larger, well above empirical upper limits. Conclusions. We find the situation analogous to that in the neutron star progenitor mass range, and conclude that magnetic torques may be required to understand the slow rotation of compact stellar remnants in general.