Related papers: Towards a Global Evolutionary Model of Protoplanet…
We review the current status of studies on accretion and protoplanetary disks of young stars with large-scale magnetic fields. Observational data on magnetic fields of the disks are compiled and analysed. Modern analytical and numerical MHD…
This review introduces physical processes in protoplanetary disks relevant to accretion and the initial stages of planet formation. After a brief overview of the observational context, I introduce the elementary theory of disk structure and…
The magnetocentrifugal disk wind mechanism is the leading candidate for producing the large-scale, bipolar jets commonly seen in protostellar systems. I present a detailed formulation of a global, radially self-similar model for a non-ideal…
Computing the flow from externally FUV irradiated protoplanetary discs requires solving complicated and expensive photodissociation physics iteratively in conjunction with hydrodynamics. Previous studies have therefore been limited to 1D…
Magnetically-driven disk winds would alter the surface density slope of gas in the inner region of a protoplanetary disk $(r \lesssim 1 {\rm au})$. This in turn affects planet formation. Recently, the effect of disk wind torque has been…
Planetesimal formation via the streaming and gravitational instabilities of dust in protoplanetary disks requires a local enhancement of the dust-to-gas mass ratio. Radial drift of large grains toward pressure bumps in gas disks is a…
This is a draft chapter for a book, entitled Physical Processes in Circumstellar Disks around Young Stars, which is scheduled for publication by the University of Chicago Press as one of its Theoretical Astrophysics Series volumes. Sect. 1…
Surveys of star-forming regions reveal that the dust mass of protoplanetary discs decreases by several orders of magnitude on a timescale of a few million years. This decrease in the mass budget of solids is likely due to the…
Understanding the complex evolution of protoplanetary disks (PPDs) and their dispersal via energetic stellar radiation are prominent challenges in astrophysics. It has recently been established that specifically the X-ray luminosity from…
Self-similar and semi-analytical solutions are found for the height-averaged equations govern the dynamical behavior of a polytropic, self-gravitating disk under the effects of winds, around the nascent object. In order to describe time…
Angular momentum transport in protostellar disks can be achieved by the action of a large scale magnetic field that runs vertically through the disk. The magnetic field centrifugally drives material from the disk surfaces into a wind,…
A variety of processes play a role in the evolution of protostellar disks. Here I focus on the uncertain issue of magnetic field-disk coupling and its implications for magnetically-driven turbulence and disk-driven winds. At present it is…
Planet formation models rely on knowledge of the physical conditions and evolutionary processes in protoplanetary disks, in particular the grain size distribution and dust growth timescales. In theoretical models, several barriers exist…
The role of convection in the gas-dust accretion disk around a young star is studied. The evolution of a Keplerian disk is modeled using the Pringle equation, which describes the time variations of the surface density under the action of…
Protoplanetary discs form and evolve in a wide variety of stellar environments and are accordingly exposed to a wide range of ambient far ultraviolet (FUV) field strengths. Strong FUV fields are known to drive vigorous gaseous flows from…
Millimeter astronomy provides valuable information on the birthplaces of planetary systems. In order to compare theoretical models with observations, the dust component has to be carefully calculated. Here, we aim to study the effects of…
The evolution of protoplanetary disks is dominated by the conservation of angular momentum, where the accretion of material onto the central star is driven by viscous expansion of the outer disk or by disk winds extracting angular momentum…
The conventional accretion disk lore is that magnetized turbulence is the principal angular momentum transport process that drives accretion. However, when dynamically important large-scale magnetic fields thread an accretion disk, they can…
Describing the large-scale field topology of protoplanetary disks faces significant difficulties and uncertainties. The transport of the large-scale field inside the disk plays an important role in understanding its evolution. We aim to…
[Abridged] Aims. We provide an important step toward a better understanding of the magnetorotational instability (MRI)-dust coevolution in protoplanetary disks by presenting a proof of concept that dust evolution ultimately plays a crucial…