On the origin of the rotation of massive stars
arXiv:2605.06872 · doi:10.1051/0004-6361/202658987
Abstract
We explore the origin of the rotation rates of massive stars. Contrary to their low-mass siblings, most massive stars do not have detectable magnetic fields, so that star-disk interaction models used for the formation of rotating low-mass stars do not apply. We investigate whether the magnetic fields of protostellar jets present in the parent molecular cloud prevent the protostar from reaching the critical angular velocity. Starting from the gravitational collapse of a molecular cloud, we run two two-dimensional radiation-gravito-magnetohydroynamical simulations to study the formation of an accretion disk and the launching of magnetically-driven protostellar outflows (of particular interest is the formation of a magnetocentrifugal jet originating from the protostar and inner disk). We then study the angular momentum transfer from the disk and jet onto the protostar. Finally, we compute one-dimensional stellar evolution models of the pre-main sequence including our results from the disk-jet simulations and follow the angular momentum redistribution within the structure of the protostar. We find that the angular momentum transported outwards by the magnetically-driven protostellar outflows is sufficient for keeping the protostar below the critical speed at all times. Moreover, we are able to link the strength of the jet, and thus the rotation rate at the end of the accretion epoch, to the initial conditions for star formation. Our results show that the jet strength produces a variety of stellar rotation rates, suggesting that protostellar jets fix the rotation rate of massive stars.
Accepted for publication in Astronomy & Astrophysics
References in corpus (21)
- PLUTO: a Numerical Code for Computational Astrophysics
- Circumventing the radiation pressure barrier in the formation of massive stars via disk accretion
- The effect of magnetic topology on thermally-driven winds: towards a general formulation of the braking law
- Accretion-Powered Stellar Winds II: Numerical Solutions for Stellar Wind Torques
- Magnetic Fields and Rotations of Protostars
- Accretion-Powered Stellar Winds III: Spin Equilibrium Solutions
- Modeling disk fragmentation and multiplicity in massive star formation
- The IACOB project. VII. The rotational properties of Galactic massive O-type stars revisited
- Stellar Rotation in Field and Cluster B-Stars
- Rotational evolution of solar-type protostars during the star-disk interaction phase
- Collapse of turbulent massive cores with ambipolar diffusion and hybrid radiative transfer II. Outflows
- Makemake + Sedna: A Continuum Radiation Transport and Photoionization Framework for Astrophysical Newtonian Fluid Dynamics
- Snapshot of a magnetohydrodynamic disk wind traced by water maser observations
- Modeling disks and magnetic outflows around a forming massive star: I. Investigating the two layer-structure of the accretion disk
- The IACOB project VIII. Searching for empirical signatures of binarity in fast-rotating O-type stars
- Modeling disks and magnetic outflows around a forming massive star: II. Dynamics of jets from massive protostars
- Magnetic Braking of Accreting T Tauri Stars II: Torque Formulation Spanning Spin-Up and Spin-Down Regimes
- What governs the spin distribution of very young < 1 Myr low mass stars
- Protostellar Outflows at the EarliesT Stages (POETS) V. The launching mechanism of protostellar winds via water masers
- Gas infall via accretion disk feeding Cepheus A HW2
- The magnetic field of a magnetohydrodynamic disk wind: Water maser observations and simulations