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Potential Theory in Astrophysics. Wu Yue, THCA. General Results. Gravitational Potential. Poisson Equation. Potential Energy. Spherical Systems. Spherical Systems. Two Important Quantities. Some Examples for Spherical Systems. Point Mass. Some Examples for Spherical Systems.
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Potential Theory in Astrophysics Wu Yue, THCA
Some Examples for Spherical Systems • Point Mass
Some Examples for Spherical Systems • Homogeneous sphere
Some Examples for Spherical Systems • Isochrone potential
Some Examples for Spherical Systems • Modified Hubble profile
Some Examples for Spherical Systems • Power-law density profile
Potential-Density Pairs for Flattened Systems • Plummer’s model(1911) • Kuzmin’s model(1956)(Toomre’s model 1)
Potential-Density Pairs for Flattened Systems • Miyamoto-Nagai’s model(1975) • Toomre’s model n(1962)
Potential-Density Pairs for Flattened Systems • Logarithmic Potentials
Poisson’s Equation in Very Flattened Systems • The simple form of Poisson’s equation applies to almost any thin disk system
Poisson’s Equation in Very Flattened Systems • The solution of Poisson’s equation in a thin disk can be decomposed into two steps • (i) Approximate the thin disk as a surface density layer of zero thickness and determine the potential in the plane of the disk • (ii)At each radius R solve the simple form of Poisson’s equation to find the vertical variation of
Ellipsoidal Systems-Axisymmetric System • Oblate Spheroidal Coordinates
Potential of Our Galaxy • photometric method • dynamical method