Stellar Orbits: Lindblad Resonances and Collisionless Boltzmann Equation

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Description

This lecture covers weak bars, the Lindblad resonances, orbit families in realistic bars, the collisionless Boltzmann equation, the distribution function of stellar systems, solutions of the collisionless Boltzmann equation, stellar orbits in weak rotating bars, resonances, and problematic terms. It also discusses the Miyamoto-Nagai and Plummer potential models, Lindblad resonances, and equilibria of collisionless systems. The instructor emphasizes the importance of self-consistent galaxy models and the assumptions made in studying large stellar systems.

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https://mediaspace.epfl.ch/media/0_ohine2i2

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Related concepts (34)

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In astronomy, stellar kinematics is the observational study or measurement of the kinematics or motions of stars through space. Stellar kinematics encompasses the measurement of stellar velocities in the Milky Way and its satellites as well as the internal kinematics of more distant galaxies. Measurement of the kinematics of stars in different subcomponents of the Milky Way including the thin disk, the thick disk, the bulge, and the stellar halo provides important information about the formation and evolutionary history of our Galaxy.

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Stellar parallax

Stellar parallax is the apparent shift of position (parallax) of any nearby star (or other object) against the background of distant stars. By extension, it is a method for determining the distance to the star through trigonometry, the stellar parallax method. Created by the different orbital positions of Earth, the extremely small observed shift is largest at time intervals of about six months, when Earth arrives at opposite sides of the Sun in its orbit, giving a baseline distance of about two astronomical units between observations.

List of stellar streams

This is a list of stellar streams. A stellar stream is an association of stars orbiting a galaxy. It was once a globular cluster or dwarf galaxy that has now been torn apart and stretched out along its orbit by tidal forces. An exception in the list about Milky Way streams given below is the Magellanic Stream, composed of gas (mostly hydrogen) although in 2023 a population of some star has been described inside it.

Stellar magnetic field

A stellar magnetic field is a magnetic field generated by the motion of conductive plasma inside a star. This motion is created through convection, which is a form of energy transport involving the physical movement of material. A localized magnetic field exerts a force on the plasma, effectively increasing the pressure without a comparable gain in density. As a result, the magnetized region rises relative to the remainder of the plasma, until it reaches the star's photosphere.