2003 Fall Astronomy 403:
Astrophysics of the Insterstellar Medium (3 units)
Instructor Information:
Prerequisites: MATH 216, and prior or concurrent enrollment in PHYSICS 240 (or 260).
Course Schedule
Primary Textbook:
"The Physics of the Interstellar Medium (2nd edition)" by J.E. Dyson and D.A. Williams
(Copies should be available at Ulrich's and online bookstores; one copy has been placed on reserve at the Shapiro Science Library)
Recommended Readings:
Other potentially useful texts will be placed on reserve at the Shapiro Science Library. These include:
- "The Physics of Astrophysics. Volumes I (Radiation) and II (Gas Dynamics)" by Frank Shu
- "Physical Processes in the Interstellar Medium" by Lyman Spitzer, Jr
- "Microwave Spectroscopy" by Charles Townes and Art Schawlow
- "Astrophysics of the Diffuse Universe" by Michael A. Dopita and Ralph S. Sutherland
This course examines the various types of gaseous components and their interaction with stars through the processes of star formation, stellar mass loss, photoionization of gas by hot stars, and supernova explosions. The interstellar medium (the gas between stars) comprises a wide variety of material that interacts closely, and often violently, with individual stars and the host galaxy. First, the underlying atomic and molecular physics is developed and then we examine how gas is ionized by hot stars and by supernova remnants. We analyze the content of the cold pervasive atomic and molecular gas in the galaxy, how it often lies in spiral arms, and why giant molecular clouds are the most active sites of star formation. Finally, recent discoveries are highlighted, such as the presence of galactic "cirrus" as seen from the dust distribution.
Grades in this course will be based on several components. There will be regular homework assignments, every one or two weeks, covering the lectures and assigned reading (generally from the course textbook, but also including outside sources). There will be one conventional hour-long exam given during the semester (a midterm) plus a 2-hour final exam; these exams will account for 45% of your final grade. Lastly, participation in classroom discussions will be an important component of your grade as well. The final grading will be done according to the following table:
| Assignment | Percentage |
| Homework | 40% |
| Final Exam | 30% |
| Midterm Exam | 15% |
| Participation | 15% |
Homework Policies:
Late homework is accepted, but suffers a 2-letter-grade penalty for each day late. While you may work in groups, each problem set should reflect your own understanding and be in your own words. Credit will not be given for answers that do not have adequate derivation (i.e., show your work).
Class Schedule for AY403: Last updated 2003Oct22 (schedule subject to change)
| Date | Readings | Topics | Homework |
| Wed Sep 3 | D&W Ch.1 | Introduction | |
| Fri Sep 5 | Ch. 2 | How we obtain information on the interstellar medium
(Review of some basic physics: thermodynamics, 2-level atom, spectral line formation, radiative transfer, continuum radiation) |
|
| Mon Sep 8 | |||
| Wed Sep 10 | |||
| Fri Sep 12 | |||
| Mon Sep 15 | |||
| Wed Sep 17 | Ch. 3 | Microscopic processes (collisional processes, heating, cooling, molecule formation) | #1 due |
| Fri Sep 19 | |||
| Mon Sep 22 | |||
| Wed Sep 24 | References:Wolfire article, Dickey/Lockman 1990 | Neutral HI regions (heating, cooling, galactic distribution); Multi-phase (neutral) ISM | #2 due |
| Fri Sep 26 | |||
| Mon Sep 29 | |||
| Wed Oct 1 | Ch. 4 | Dust (optical properties, formation, destruction, composition) | #3 due |
| Fri Oct 3 | |||
| Mon Oct 6 | |||
| Wed Oct 8 | Ch. 5 | Radiatively-excited (HII) regions (ionization, stromgen sphere, radio emission, effect of dust/metals) | #4 due |
| Fri Oct 10 | |||
| Mon Oct 13 | No Class (Fall Break) | ||
| Wed Oct 15 | (HII regions continued) | ||
| Fri Oct 17 | |||
| Mon Oct 20 | Ch. 6 | Introduction to fluid mechanics (hydrodynamics, Euler equations, shocks, magneto-hydrodynamics) | #5 due |
| Wed Oct 22 | |||
| Fri Oct 24 | |||
| Mon Oct 27 | In-class review for Midterm | ||
| Wed Oct 29 | Midterm Exam (tentative schedule) | ||
| Fri Oct 31 | Ch 6. (continued) | (continued) | |
| Mon Nov 3 | Ch. 7 | Gas dynamics (photo-ionized nebula, stellar winds, supernovae, energy budget of ISM) | |
| Wed Nov 5 | #6 due | ||
| Fri Nov 7 | |||
| Mon Nov 10 | |||
| Wed Nov 12 | outside reading (TBD) | Molecular gas/clouds (H2, CO, astrochemistry, observations) | #7 due |
| Fri Nov 14 | |||
| Mon Nov 17 | |||
| Wed Nov 19 | Ch. 8 | Star formation (gravitational collapse, virial theorem, magnetic fields, rotation, observations) | |
| Fri Nov 21 | |||
| Mon Nov 24 | |||
| Wed Nov 26 | Guest Lecture | ||
| Fri Nov 28 | No Class (Thanksgiving) | ||
| Mon Dec 1 | (star formation continued) | ||
| Wed Dec 3 | Ferriere 2001 | Overview of Galactic ISM (Putting it all together, ISM in pictures, and Review Session for Final Exam | #8 due |
| Fri Dec 5 | |||
| Mon Dec 8 | |||
| Wed Dec 10 | Class Presentations (Last day of Class) | #9 due |
The following links may be useful at various points during the class. Please send me additional links you have found useful, and I will include these for your classmates' benefit.
Interstellar Medium:
Images:
Other: