Theoretical Atomic Physics

Dr. T.M. Luke
(519) 661-2111, ext. 88796
Room 121 Western Science Centre
tluke@julian.uwo.ca

Current Research Program:

Structure and Radiative Transitions in Complex Ions: My research involves large scale computations in the field of atomic physics. We are interested in understanding the nature of high temperature plasmas such as are found inside stars and fusion reactors. The ions in these plasmas are usually stripped of one or more electrons and they undergo transitions between excited and ground states, giving off characteristic radiation in the process. When this radiation is detected outside the plasma using some kind of telescope, the frequency/intensity patterns tell us a great deal about the physical state of the plasma - information that may not be available otherwise.

Interpreting these patterns of the observed spectrum depends on a detailed knowledge of radiative transition rates for transitions between excited states of atoms and ions. This can be obtained either by lab measurements or by modelling the atoms mathematically and solving the resulting equations which is what I do. The atoms in the vicinity of iron in the periodic table are of special interest in stellar astrophysics and my present work concentrates on them. The work is very demanding in computing resources and much of its interest, apart from obtaining useful data, lies in developing numerical and computational techniques that will enable us to carry out the calculations efficiently and accurately.

Selected Recent Publications:

“On the Inverse Eigenvalue Problem for Matrices” (with A.S. Deakin) J. Phys. A: Math. Gen. 25 (1992) 635-698.

“On the Contribution of an Efficient Basis for CI Calculations: Application to a Spin Forbidden Transition in P II” (with L. LaJohn) J. Phys. B: At. Mol. Opt. Phys. 26 (1993) 863-871.

“Decay Rates and Lifetimes of the 4p6,4 P and 4p6 D Levels of CrII” (with K. Aashamar) J. Phys. B:At. Mol. Opt. Phys. 27 (1994) 1091-1103.

“Relativistic Transition Rates for 3 Quartet Multiplets in Neutral Vanadium” Physica Scripta 54 (1996) 346-351.

“Allowed and forbidden Transitions in Singly Ionized Vanadium” J. Phys. B:At. Mol. Opt. Phys. 30 (1997) 4223-4239.

“Transition Rates in Singly Ionized Titanium”, Can. J. Phys. 77 (1999) 571-583.