Matteo Cantiello edited Abstract.tex  almost 11 years ago

Commit id: 1194c1859fcd0fbdc564b7666d0d55cb0bbf76c9

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Stars are born rotating. Observations of stars on their main sequence reveal that bulk of stars with mass above $$1.5\mso$$ $1.5\mso$  are spinning fairly rapidly. While their pre-main sequence evolution is complex, a common assumption is that these stars reach a state of quasi-solid rotation when they start burning hydrogen at the zero age main sequence. From there on their evolution has to account for loss and internal redistribution of angular momentum. Stellar evolution models that include the   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 range1. . . 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.