What does L star mean in the Schechter function?

  • #1
I_laff
41
2
I'm trying to understand the Schechter function, I read on Wikipedia that the L star term in the function is the 'characteristic galaxy luminosity where the power-law form of the function cuts off'. What does this mean exactly?
 

Answers and Replies

  • #2
phyzguy
Science Advisor
5,026
2,025
It's just an empirical fitting function to the brightness distributions. It's found empirically that the number of galaxies in a certain brightness range increases as a power law at the faint end, but drops off more quickly (exponentially) at the bright end. The L* luminosity is where the function transitions from one behavior to the other. These slides have a nice description.
 
  • #3
I_laff
41
2
Thanks for the explanation [emoji846]
 
  • #4
CygnusX-1
125
93
L* is the luminosity of a giant galaxy like the Milky Way or Andromeda. Such galaxies are rare, and galaxies much brighter are even rarer.

See this article on super spiral galaxies for more.
 

Suggested for: What does L star mean in the Schechter function?

Replies
1
Views
9K
Replies
1
Views
4K
Replies
2
Views
2K
  • Last Post
Replies
3
Views
4K
Replies
3
Views
2K
Replies
1
Views
3K
  • Last Post
Replies
5
Views
5K
Replies
7
Views
1K
Replies
9
Views
13K
Replies
24
Views
6K
Top