Astronomy 440
Fall 2013 Semester
Instructor: Ted Daub
Email: ctdaub@gmail.com
Office: PA-230
Hours: MWF 1030-1130, 1500-1530
(or, by appointment)
Phone: 619-594-1414 (office)
619-741-6420 (home)
GENERAL INFORMATION
Textbook
An Introduction to Modern Astrophysics by B.W. Carroll and D.A. Ostlie, 2nd
edition, Pearson/AddisonWesley, 2007. There is much material in this book that will not
be taken up in Astronomy 440; although there is a shorter version of the text dealing
specifically with our topic of stellar astrophysics; the cost is not much less, and that one
would not be able to serve (as this one does) as a potential text for Astronomy 450 as
well.
Homework
There will be frequent homework assignments. Your write-up of each one should
be neat, organized, sufficiently detailed to allow me to easily follow your reasoning and
analysis, and submitted on the due date. Always, unless it is clearly unnecessary,
include a commentary on your results; for example: How reasonable are they? What
was learned from the results and/or from the process of of obtaining them? In regard to
this commentary, I encourage you to to discuss the results with each other, but please
work privately on the assignments. Do not be hesitant, however, to discuss aspects of
an assignment with me - for example, if you need a boost to get started or if you get
stuck midstream..
Exams
There will be two exams, a midterm and a final. Each exam will have separate inclass and take-home components. You may bring a “crib sheet” to the in-class portion of
any exam; specifically, a normal-sized sheet of typing paper with any notes you care to
include written on one side. The midterm exam will cover, approximately, the topics on
the first page of the Outline of Topics. The final exam will be comprehensive, but heavily
weighted toward the topics on the second page of the Outline of Topics. The in-class
portion of the final exam is scheduled for Monday 16 December at 1300. The take-home
portion of that exam will be due no later than 1600 Wednesday 18 December.
Course Grade
The final course grade will be determined by averaging grades on the homework
and exams according to these weighting factors:
Midterm Exam......30%
Final Exam...........40%
Homework............30%
Astronomy 440
Fall 2013 Semester
Outline of Topics
INTRODUCTION
Astrophysics as Science
Some Mathematics and Physics Preliminaries
OBSERVATIONAL DATA
Distance (3.1), Mass (7), and Radius
Radiative Flux, Luminosity, and Magnitude
Spectra
Some Correlations
MASS CONSERVATION AND HYDROSTATIC EQUILIBRIUM
ATOMIC STRUCTURE
EQUILIBRIUM STATES
Thermal Equilibrium, Thermodynamic Equilibrium (TE)
Consequences of TE
Excitation and Ionization of Atomic Particles
Kinetic Energies of Atomic Particles
Photons
Using the Distribution Functions
EQUATIONS OF STATE
ENERGY CONTENT
Thermal, Gravitational, Ionization
Virial Theorem
RADIATIVE TRANSFER
Description of the Radiation Field
Specific Intensity, Mean Intensity, Flux
Temperatures of Stars
Equation of Radiative Transfer
Emission Coefficient
Absorption Coefficient
Equation of Transfer and Some Elementary Solutions
MEAN FREE PATHS
LOCAL THERMODYNAMIC EQUILIBRIUM (LTE)
ENERGY TRANSPORT
Radiative
Convective
Conductive
ENERGY GENERATION
Equation of Thermal Equilibrium
Gravitational
Nuclear
THE STRUCTURE OF GRAVITATING GAS SPHERES (STARS)
Fundamental Equations and Schwartzschild Variables
Numerical Integration Techniques
Formation, Pre-Main Sequence Stages
Main Sequence and Post-Main Sequence Stages
Star Clusters as Tests of Stellar Structure and Evolution Theory
Final Stages
Mass < 8 Solar Masses
Mass > 8 Solar Masses
EMERGENT STELLAR SPECTRUM
Formal Solution to the Equation of Transfer
Radiative Equilibrium and Constancy of Radiative Flux
Solution for a Linear Source Function
Emergent Specific Intensity
Emergent Flux
Temperature vs Optical Depth
Explanation for the Color-Color Curve
SPECTRAL LINES
Spectral Line Profiles and Line Broadening
Equivalent Width and Curve of Growth
POSSIBLE ADDITIONAL TOPIC
THE INTERSTELLAR MEDIUM
Dust Grains
HI and HII regions