Appendices: Definitions

The Structure, Stability, and Dynamics
of Self-Gravitating Systems

Joel E. Tohline
tohline@rouge.phys.lsu.edu

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p = 3.141592654
(For a more accurate representation of p, click here).

c = speed of light
3.00 ´ 10¹⁰ cm sec^-1

G = gravitational constant
6.67 ´ 10^-8 cm³ gm^-1 sec^-2

h = Planck constant
6.63 ´ 10^-27 erg sec

k = Boltzmann constant
1.38 ´ 10^-16 erg deg^-1

Ā = gas constant = k/m_p
8.31 ´ 10⁷ erg deg^-1 mole^-1

E_grav = See Virial.text.shtml
E_rot = See Virial.text.shtml
H = See Spherical General Introduction
I = See Virial.text.shtml
n = polytropic index: [ dimensionless ]
An exponent defining the power-law relationship between P and r in the structural, polytropic expression; defined by its use in equation [0.0.0.6].
P = Gas pressure: [ gm cm^-1 sec^-2 = energy per unit volume = force per unit area ]
t = time: An independent variable in the principal governing equations.
T = Gas temperature: [ degrees Kelvin ]
u = internal energy density = e r: [ gm cm^-1 sec^-2 = energy per unit volume ]
U = See Virial.text.shtml
v = velocity vector = Dx: [ cm sec^-1 ]
x = position vector: An independent variable in the principal governing equations.
e = specific internal energy = u/r: [ cm² sec^-2 = energy per unit mass ]
g = ratio of specific heats: [ dimensionless ]
F = gravitational potential: [ cm² sec^-2 = energy per unit mass ]
m = mean molecular weight: Defined such that 1/m = the number of free particles; (electrons + protons + neutral atoms + ions) per proton mass.; {units = 1/mole}
r = mass density: [ gm cm^-3 ]