Inside-out Planet Formation. V. Structure of the Inner Disk as Implied by the MRI

Simple item page
dc.citation.issue2
dc.citation.rankM21
dc.citation.spage144
dc.citation.volume861
dc.contributor.authorMohanty, Subhanjoy
dc.contributor.authorJankovic, Marija R.
dc.contributor.authorTan, Jonathan C.
dc.contributor.authorOwen, James E.
dc.date.accessioned2023-05-09T11:25:35Z
dc.date.available2023-05-09T11:25:35Z
dc.date.issued2018-07-13
dc.description.abstractThe ubiquity of Earth- to super-Earth-sized planets found very close to their host stars has motivated in situ formation models. In particular, inside-out planet formation is a scenario in which planets coalesce sequentially in the disk, at the local gas pressure maximum near the inner boundary of the dead zone. The pressure maximum arises from a decline in viscosity, going from the active innermost disk (where thermal ionization yields high viscosities via the magnetorotational instability [MRI]) to the adjacent dead zone (where the MRI is quenched). Previous studies of the pressure maximum, based on α-disk models, have assumed ad hoc values for the viscosity parameter α in the active zone, ignoring the detailed MRI physics. Here we explicitly couple the MRI criteria to the α-disk equations, to find steady-state solutions for the disk structure. We consider both Ohmic and ambipolar resistivities, a range of disk accretion rates (10−10–10−8 M⊙ yr−1), stellar masses (0.1–1 M⊙), and fiducial values of the non-MRI α-viscosity in the dead zone (αDZ = 10−5 to 10−3). We find that (1) a midplane pressure maximum forms radially outside the dead zone inner boundary; (2) Hall resistivity dominates near the inner disk midplane, perhaps explaining why close-in planets do not form in ∼50% of systems; (3) X-ray ionization can compete with thermal ionization in the inner disk, because of the low steady-state surface density there; and (4) our inner disks are viscously unstable to surface density perturbations.
dc.identifier.doi10.3847/1538-4357/aabcd0
dc.identifier.issn1538-4357
dc.identifier.scopus2-s2.0-85050747085
dc.identifier.urihttps://pub.ipb.ac.rs/handle/123456789/16
dc.identifier.wos000438575500009
dc.language.isoen
dc.publisherAmerican Astronomical Society
dc.relation.ispartofThe Astrophysical Journal
dc.relation.ispartofabbrApJ
dc.rightsrestrictedAccess
dc.titleInside-out Planet Formation. V. Structure of the Inner Disk as Implied by the MRI
dc.typejournal-article
dc.type.versionpublishedVersion
Files
Original bundle
Now showing 1 - 1 of 1
Thumbnail Image
Name:
Mohanty_2018_ApJ_861_144.pdf
Size:
1.72 MB
Format:
Adobe Portable Document Format
Description:
Download
Collections
Publications