# Allen H. Boozer

**Applied Physics**

287B Eng Terrace

Mail Code: 4701

New York, NY 10027

Phone: 1-212-854-4785

Email: ahb17@columbia.edu

CV

**Research Specialty**

Plasma theory, theory of magnetic confinement for fusion energy, nonlinear dynamics

**Education**

Ph.D. Cornell University, 1970.

Received a bachelor-of-arts degree in physics from the University of Virginia in 1966 and a doctorate in physics from Cornell University in 1970. Elected to Phi Beta Kappa as an undergraduate and received Woodrow Wilson and National Science Foundation fellowships as a graduate student.

**Employment**

Was an officer in the U.S. Air Force from 1970 to 1974 where he received the Commendation medal. From 1974 to 1986, was a Research Physicist at the Princeton Plasma Physics Laboratory and was acting head of the theoretical division from 1985 to 1986. From 1986 to 1994, was a Professor of Physics at the College of William and Mary, and from 1994 to the present a Professor of Applied Physics at Columbia.

**Honors**

In 1989, was elected to scientific membership in the German Max Planck Society (Auswartiges Wissenschafliches Mitglied der Max-Planck-Gesellschaft). Was made a Fellow of the American Physical Society in 1982 and held the first U.S.-Japan fusion-theory visiting professorship at Nagoya University in 1982.

**Officer and Associate Editor Positions**

In 1998, was elected to the three-year chair sequence of the APS Division of Plasma Physics and was Secretary/Treasurer of APS Division of Plasma Physics in 1989-1990. Was an Associate Editor of the Physics of Plasmas 1992-94, on the Editorial Board for Plasma Physics and Controlled Fusion 1992-95, and president of the University Fusion Association 1992.

**Selected Publications**

Has 204 refereed publications. Recent publications include:

1. Control of stellarator properties illustrated by a Wendelstein7-X equilibrium, A. H. Boozer and L. P. Ku, Physics of Plasmas 18, 052501 (2011)

2. Control of non-axisymmetric magnetic perturbations in tokamaks, A. H. Boozer, Fusion Science and Technology 59, 561 (2011)

3. Mathematics and Maxwell's equations, A. H. Boozer, Plasma Physics and Controlled Fusion 52, 124002 (2010)

4. Current density and plasma displacement near perturbed rational surfaces, A. H. Boozer and N. Pomphrey, Physics of Plasmas 17, 110707 (2010)

5. Control of non-axisymmetric toroidal plasmas, A. H. Boozer, Plasma Physics and Controlled Fusion 52, 104001 (2010)

6. Stellarators and the path from ITER to DEMO, Allen H. Boozer, Plasma Physics and Controlled Fusion 50, 124005 (2008)

7. Error field correction in ITER, Jong-Kyu Park, Allen H. Boozer, Jonathan E. Menard, Michael J. Schaffer, Nucl. Fusion 48, 045006 (2008)

8. Perturbed plasma equilibria, A. H. Boozer and Carolin Nührenberg, Physics of Plasmas 13, 102501 (2006)

9. Stability of pure electron plasmas on magnetic surfaces, A. H. Boozer, Physics of Plasmas 11, 4709-4712 (2004)

10. Physics of magnetically confined plasmas, A. H. Boozer, Reviews of Modern Physics 76, 1071-1141 (2004)

**Research Contributions**

1. Demonstrated, Phys. Fluids 24, 1999 (1981), the existence of coordinates in which the magnetic field has simple covariant and contravariant forms. These magnetic coordinates simplify calculations of plasma equilibrium and transport and are usually called Boozer coordinates.

2. Found the first general method for determining magnetic coordinates, Phys. Fluids 25, 520 (1982), showed the poloidal flux is a one and a half degree of freedom Hamiltonian for the lines of a magnetic field, or more generally for any divergence-free field, Phys. Fluids 26, 1288 (1983), and was a co-developer of a technique for determining the field-line Hamiltonian in canonical variables for a given magnetic field, J. Comp. Phys. 73, 107 (1987).

3. Showed that the standard equations for the guiding center motion of particles are inconsistent with Hamiltonian mechanics and Liouville's equation, gave a form for the guiding center motion that is consistent with Hamil-tonian mechanics, Phys. Fluids 23, 904 (1980).

4. Developed a general time dependent Hamiltonian in canonical form for the guiding center motion of particles for the non-relativistic, Phys. Fluids 27, 2110 (1984), and later for the relativistic, Phys. Plasmas 3, 3297 (1996), case.

5. Was a co-developer of many of the major techniques for carrying out Monte Carlo calculations of transport in asymmetric devices such as stellarators, Phys. Fluids 24, 851 (1981), Phys. Plasmas 2, 610 (1995), and Phys. Plasmas 10, 103 (2003).

6. Was an author of the first paper on the stochastic loss of alpha particles, Phys. Rev. Lett. 47, 647 (1981). This loss determines the maximum ripple, due to the finite number of toroidal field coils, that can be tolerated in an ignited tokamak plasma.

7. Was an author of the first paper to explain the loss of high energy particles due to the fishbone instability, Phys. Fluids 26, 2958 (1983), which initiated the modern interest in the interaction of particle orbits and MHD effects.

8. Was the co-inventor of electron cyclotron current drive and more generally the method of driving current by selectively heating high energy particles, Phys. Rev. Lett. 45, 720 (1980) and U.S. patent number 4,425,295, which was issued in 1984.

9. Determined the minimum power required to drive a current that is carried by high energy (tail) electrons, Phys. Fluids 31, 591 (1988). This paper demonstrated a steady-state tokamak was possible only with a strong bootstrap current.

10. Was an author on the papers that first defined the two known methods for obtaining confined particle orbits in stellarators: (i) having all minima of the field strength on a magnetic surface have the same value, Phys. Rev. Lett. 48, 322 (1982), which is the confinement principle of the W7- X stellarator and (ii) quasisymmetry, Phys. Fluids 26, 496 (1983), which is the confinement principle of the HSX and the NCSX stellarators.

11. Co-authored the first paper showing the limitation on the plasma pressure in a stellarator due to the breakup of the magnetic surfaces, Phys. Fluids 27, 2446 (1984).

12. Working with doctoral students, gave the general form for the magnetic field strength in toroidal plasma equilibria and the minimal breaking of quasisymmetry that is mathematically required, Phys. Fluids B 3, 2805 and 2822 (1991).

13. Developed the theory of error field amplification and rotation damping in tokamak plasmas, Phys. Rev. Lett. 86, 5059-5061 (2001) and the circuit method of dealing with resistive wall modes in tokamaks.

14. Showed that magnetic systems that are doubly periodic (as in a toroidal plasma) and non-periodic (as in astrophysics) have fundamentally different reconnection phenomena, Phys. Rev. Lett. 88: art. no. 215005 (2002).

15. Gave the general form of Ohm's law for a spatially averaged field that in-corporates the helicity conserving properties of resistive MHD, J. Plasma Phys. 35, 133 (1986), derived the constraints of magnetic helicity con-servation on natural dynamos, Phys. Fluids B 5, 2271 (1993), and gave implications for the solar corona in Magnetic Helicity in Space and Laboratory Plasmas edited by M. R. Brown and R. C. Canfield (American Geophysical Union, Washington, DC, 1999) p.11-16. In particular it was shown that runaway electron effects cause the development of a corona on any star with a magnetic field and an outer convective zone.