Course Meeting Times

Lectures: 2 sessions / week, 1.5 hours / session


8.03 Physics III

Course Description

This course highlights the properties and behavior of low-temperature plasmas in relation to energy conversion, plasma propulsion, and gas lasers. The course includes material on the equilibrium (energy states, statistical mechanics, and relationship to thermodynamics) and kinetic theory of ionized gases (motion of charged particles, distribution function, collisions, characteristic lengths and times, cross sections, and transport properties). In addition, the course discusses gas surface interactions (thermionic emission, sheaths, and probe theory) and radiation in plasmas and diagnostics.

Course Textbook

Buy at Amazon Mitchner, Morton, and Charles H. Kruger. Partially Ionized Gases. Vol. 8. John Wiley & Sons Inc, 1973. ISBN: 9780471611721.


Assignments (5 homework problem sets total) 50%
Quizzes (2 total) 50%


1 Fundamentals of Plasma Physics. Larmor motion. Debye shielding. Plasma frequency.  
2 Motion of Charges in Uniform E and B fields. Diamagnetism. ExB drift. Alfven waves.  
3 Effects of an Inhomogeneous Magnetic Field. Inertia and grad-B drifts. Parallel drifts and magnetic mirrors.  
4 Relationship between drifts and the fluid picture.  
5 Time-varying B field. Adiabatic Invariants. Homework 1 due
6-7 Collision Theory. Energy and momentum transfer. Calculation of scattering cross sections: the hard sphere model and power-law potentials.  
8 Kinetic Theory. Vlasov and Boltzmann Equations. Collisional terms.  
9 Boltzmann’s H-Theorem. Relationship between H and S (Entropy).  
10-11 The Equilibrium Distribution and its Properties. Characteristic energies and velocities for a Maxwellian distribution. Homework 2 due during Lecture 10
12 Equilibrium in a Force Field. Distribution functions near repelling and attracting walls.  
13-14 Moments of the Boltzmann Equation. Mass and momentum conservation. Kinetic energy equation.  
  Quiz 1 Homework 3 due
15 Maxwellian Collisions. Ohm’s Law. Ambipolar diffusion.  
 16 The Electron Energy Equation.    
17 Plasma-Wall Interactions: Sheath and Pre-sheath. Bohm condition. Random particle and kinetic energy flux across a plane.  
18 Electrostatic Probes. Floating potential. Method of Medicus.  
19 Probes in the Orbital Motion-Limited (OML) Regime.  Homework 4 due
20-21 Equilibrium Statistical Mechanics. Quantum statistics. Classical limit. Partition function. Multi-component systems. Translational partition function.  
22 Some important results of Statistical Mechanics. Ionization equilibrium. Free electrons in metals. Black Body radiation.  
23 The Electronic Partition Function for Atoms and Ions. The vibrational and rotational partition functions. Energy levels.  
24 Radiation Transport in a Gas. Equilibrium distribution. Transport equation. Collisional operator. Spectral lines. Line-reversal pyrometer.  Homework 5 due
25 Semi-thick plasma approximation. Line radiation and broadening. Bound-free radiation. Bremsstrahlung. Escape for resonant radiation.  
  Quiz 2