光度密度[Luminosity Density] - 达人(其实～我是卧底，来自外星)

2005/04/17 | 光度密度[Luminosity Density]
类别(¤〖天文〗) | 评论(0) | 阅读(24) | 发表于 13:35: Let j be the luminosity per unit column of a spherical distribution. The the observed distribution is
(1)

where R is the vertical distance from the center, z is the horizontal distance from the center, r is the radial distance from the center, and
(2)

The mass density is given by
(3)

where is the mass/luminosity ratio and j(r) is the luminosity per unit volume. It is often parameterized by
(4)

The surface brightness is then
(5)

(6)

The mass is then given by
(7)

(8)

The circular velocity would then be
(9)

(10)

(11); 0