Year: 2014
Type: article
Abstract: We examine whether the magnetorotational instability (MRI) can serve as a mechanism of angular momentum transport in circumplanetary disks. For the MRI to operate the ionization degree must be sufficiently high and the magnetic pressure must be sufficiently lower than the gas pressure. We calculate the spatial distribution of the ionization degree and search for the MRI-active region where the two criteria are met. We find that there can be thin active layers at the disk surface depending on the model parameters, however, we find hardly any region which can sustain well-developed MRI turbulence; when the magnetic field is enhanced by MRI turbulence at the disk surface layer, a magnetically dominated atmosphere encroaches on a lower altitude and a region of well-developed MRI turbulence becomes smaller. We conclude that if there are no angular momentum transfer mechanisms other than MRI in gravitationally stable circumplanetary disks, gas is likely to pile up until disks become gravitationally unstable, and massive disks may survive for a long time.
Source: The Astrophysical Journal
Authors: Yuri I. Fujii, Satoshi Okuzumi, Takayuki Tanigawa, Shu-ichiro Inutsuka
Language: English
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: bronze
Awards: G1016807198, G1233713817, Revolving Theory of Star Formation, Origin of Satellite Systems around Giant Planets: Structure of Circumplanetary Disks, Origin of satellite systems around giant planets: Supply of building material of satellites to circumplanetary disks, Modeling the coevolution of dust and magnetic turbulence in planetesimal formation stages
OpenAlex ID: W2036368362