What are the physical processes that lead to the formation of accretion disks around young stellar objects (YSOs)?
Best insight from top research papers
The formation of accretion disks around young stellar objects (YSOs) is primarily driven by physical mechanisms such as variable disk accretion and episodic accretion. These processes result in a variety of amplitudes and light curve shapes in YSOs, indicating the presence of accretion variability. Episodic accretion in protobinary systems within gravoturbulent gas collapses leads to strong accretion bursts between companions, with varying accretion rates onto primary and secondary stars. The Vera C. Rubin Observatory's Legacy Survey of Space and Time (LSST) will enable the study of short-term and long-term variability in YSOs, emphasizing the role of accretion processes in driving these variations and providing insights into inner disk dynamics and eruptive behaviors.
Answers from top 4 papers
More filters
| Papers (4) | Insight |
|---|---|
| Variable disc accretion is a key process leading to the formation of accretion disks around YSOs, driving mid-IR variability and aiding in understanding episodic accretion phenomena. | |
15 Mar 2023 | Variable disk accretion, a predicted mechanism, drives mid-IR variability in YSOs. Eruptive YSOs exhibit characteristics like FUors, EX Lupi types, and V1647 Ori-like objects due to varied outburst parameters. |
02 Feb 2023 | Accretion processes driven by dynamics in disk-hosting YSOs lead to the formation of accretion disks, enabling exploration of short and long-term variability using Rubin Observatory's LSST multi-band filters. |
| Turbulence-induced episodic accretion in binary YSOs leads to the formation of accretion disks, with strong bursts between companions, influenced by velocity dispersion and mass ratio. |
Related Questions
What are the geological processes that cause accretion and erosion waves on beaches?4 answersAccretion and erosion on beaches are primarily influenced by various geological processes. These processes include the interaction of water motions like waves, tides, storm surge, and nearshore currents with coastal land. Additionally, factors such as beach material, slope, rainfall, and groundwater levels play a significant role in beach profile evolution. Sand mining and the presence of sea walls are identified as driving forces for erosion/accretion in placer mining beaches. The propensity for erosion is determined by analyzing the dynamical and morphological properties of the beach, with sediment removal being a key factor. Waves, as undulations between water and air, are fundamental in the transport of sediments and the genesis of coastal environments, contributing to erosion of rocky coasts and the evolution of barrier islands and beaches.
How do planets form?5 answersPlanets form through a process called core accretion, where a core grows by accumulating solids and then undergoes a gas accretion phase to become a gas giant planet. This process was initially thought to take longer than the lifetime of the gas disc, suggesting an alternative formation process. One possibility is direct gravitational collapse, where a disc fragments into bound objects that contract to become gas giant planets. However, subsequent work has shown that core accretion can occur within disc lifetimes, making disc fragmentation unlikely to play a role in the formation of close-in exoplanets. Another mechanism for planet formation is the coagulation of dust grains in a protoplanetary disk, leading to the formation of planetesimals that eventually coalesce to form planets. Planets can also form through the evolution of disks around single and binary stars, degenerate dwarfs, neutron stars, and stellar-mass black holes. The exact process of planet formation is still under debate, but these different mechanisms provide insights into the formation of planets in various contexts.
Processes of cloud dissipation and formation?5 answersCloud dissipation and formation processes are complex and involve various factors. The presence of aerosols in the lower atmosphere does not frequently cause cloud dissipation. Instead, two active processes support the formation of low clouds after clear-sky periods: horizontal advection, dominant in winter and early spring, and quiescent air mass modification, dominant in summer. During summer, low clouds or fog layers develop near the surface due to air mass modification and increased aerosol concentrations. Cloud formation and destruction can also be influenced by shock fronts, cloud-cloud collisions, and condensation instabilities, with magnetic fields playing a role in increasing cohesion. Cloud formation and dissipation involve complex interactions among dynamic, radiative, thermodynamic, microphysical, and chemical processes, which are not fully understood. Cloud modeling is challenging due to the range of spatial scales involved and the need for parameterizations to account for these interactions.
How does the comet form?4 answersComets form through the gravitational collapse of pebble clouds that are composed of dust and ice particles. These pebble clouds are formed through the streaming instability, which is a mechanism that arises from the coupling between gas and millimeter- to decimeter-sized dust aggregates. The collapse of these pebble clouds leads to the formation of planetesimals, which are kilometer-sized icy bodies that have the properties of comets. The formation of comets through the streaming instability is supported by simulations and observations of cometary nuclei. The observed high porosity and low density of comet nuclei can be explained by the compression of cm-sized porous ice/dust-mixed pebbles in collapsing pebble clouds. The dust-to-ice ratio of the pebbles must be in the range of 3 to 9 to match the observed bulk properties of comet nuclei.
How do singularities influence the accretion and assembly of protoplanetary discs during the early stages of solar system formation?5 answersSingularities in the collapse of perfect fluid clouds can have significant effects on the accretion and assembly of protoplanetary discs during the early stages of solar system formation. These singularities can result in the formation of naked singularities, which are characterized by a strong curvature where gravitational tidal forces diverge powerfully. Observational signatures of thermal accretion discs around naked singularities differ from those around black holes of the same mass, with the former being more luminous and having a spectrum with a high frequency power law segment that carries a major fraction of the total luminosity. The stability of the naked singularity formation in the collapse of dust clouds against perturbations in the initial data further supports their influence on the accretion and assembly processes. These findings have implications for understanding the formation and evolution of protoplanetary discs and the potential detection of naked singularities in astrophysical observations.
Why there is more star formation in the disk?6 answers