1. Surface Brightness Profile - NGC 3379 (giant elliptical)
Surface Brightness (mags/arcsec2)
Dashed line is a deV law
r1/4

2. King Models - A Family of Curves
deV law would be a straight line on this plot
Note: “Isothermal” sphere is classic model where density is
r( r ) ~ 1/r2
Surface Brightness
r1/4

3. Error Function

5. King Models and Observed Objects
NGC 6388
Circles: globular cluster NGC 6388
Squares: globular cluster NGC 5053
Triangles: Sculptor dwarf galaxy
NGC 5053
Sculptor Dwarf Galaxy

6. Giant Elliptical NGC 4472 (c = 2.35)
SDSS image
Solid line is King Model with c = 2.35

7. deV vs. King: NGC 3379 Dots: observations Dashed line: deV law
Solid line: King model, c = 2.2

8. Two Galaxies in Same Cluster: Dwarf E and Giant E
Dashed - Giant E, r1/4
Solid - Dwarf E, exp[-r/rs]

9. cD Galaxy - The Biggest of the Big
Line: deV
Line: deV law ?

10. Schechter Luminosity Function
The most intrinsically luminous galaxies are primarily red in color and are rare
The most intrinsically faint galaxies are the most numerous and are primarily blue in color (irregulars vastly outnumber dwarf E)
blue
red

11. “Violent Relaxation” of Star Cluster
“cold” start
minimum size
maximum size
end

12. Density Profile: Before and After Violent Relaxation
Uniform density sphere (dashed line) at start
R1/4 law at end (squares + solid line)

13. Distribution of Stellar Energies: Before, During, and after Violent Relaxation
start
end