ASTRONOMY 216 OUTLINE

			CARL HEILES

	We will probably cover topics in roughly this order:

1. HII regions as the simplest ISM structure: a known, central source.
	1.1. Ionization equilibrium.
	1.2. Radiative processes. 
	1.3. Heating and cooling: thermal equilibrium.
	1.4. Dynamics of HII regions, which involves getting into...

2. Gasdynamical Fronts.
	1.1. Shock fronts, including structure thereof and magnetic fields.
	1.2. Ionization fronts and HII region dynamics.
	1.3. Globules, photoevaporation.
	1.4. Photodissociation regions (PDR's).
	1.5. Stellar winds and supernova explosions and the ISM.
	1.6. Cloud evaporation.
	1.7. Cygnus Loop as a fascinating example (James Graham)

3.  Dust grains.
	3.1. Absorption, scattering, extinction, IR radiation.
	3.2. Astrophysical roles. 
	3.3. Sources and destruction mechanisms.

4.  The diffuse ISM: HI, the Cold Neutral Medium (CNM) and the Warm
Neutral Medium (WNM). 
	3.1. Observational methods: 21-cm line, optical and UV 
		absorption lines, far-IR emission from dust, gamma-rays, 
		the Carbon fine-structure line, other fine-structure lines. 
	3.2. Observational characteristics: elemental abundances, depletion.
	3.3. Observational characteristics: distribution, temperature,
		density.
	3.4. Theoretical considerations: thermal equilibrium, the
		two-phase model, thermal stability.

3. The diffuse ISM: The Warm Ionized Medium (WIM).
	3.1. Observational methods: dispersion, scintillation, H-alpha, radio
		recombination lines, the Carbon and Nitrogen
		fine-structure lines. 
	3.2. Observational characteristics: distribution, temperature,
		density.
	3.3. Theoretical considerations: energy and ionization 
		requirements.

5. The diffuse ISM: The Hot Ionized Medium (HIM).
	5.1. Observational methods: UV absorption lines, UV emission 
		lines, thermal 	emission, the ROSAT data. 
	5.2. Observational characteristics: distribution, temperature, 
		density.
	5.3. Theoretical considerations: heating/cooling processes, 
		energy sources, supernovae, supershells, 'blowout'.

6. The diffuse ISM: The magnetic fields and cosmic rays.
	6.1. Observational methods: Synchrotron emissivity, Faraday 
		rotation, Zeeman splitting.
	6.2. Observational characteristics: magnetic configuration and 
		field strength from the galactic to protostellar scales.

7. The diffuse ISM: overview and theoretical considerations.
	7.1. The global structure of the MW as a typical example of a galaxy. 
		COBE results.
	7.2. The McKkee-Ostriker model.
	7.3. Stellar associations and superbubbles.

8. The dense ISM: molecular clouds, star formating regions. 
	7.1. Observational methods: rotational, vibrational, and 
		electronic molecular spectra.
	7.2. Observational characteristics: temperature, density, 
		magnetic fields, kinematics, bipolar outflows. 
	7.3. Statistics and galactic distribution of molecular clouds.
	7.4. Basic theory: virial theorem, basic star formation, 
		subcritical vs supercritical, angular momentum problem.
	7.5. Basic theory of astrochemistry.