Astr 501 | Lecture 23 | Fall 2022
Maghnad Saha
Astronomy 501
Lecture 23, Oct 17 Fall 2022

Lecture Notes: pdf file

Thermodynamics of Atomic States

  • state populations: partition function
  • partition cutoff
  • ionization equilibrium: Saha equation
  • awesome example: cosmic recombination of hydrogen

Midterm Exam Discussion

hydrogen Balmer lines
the Sun in H alpha

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