Atoms and Positrons Research

Atomic structure and atomic collisions research

We perform large-scale atomic structure and scattering calculations predominantly with configuration-interaction methods.

See our publications on Positron-atom interactions
and Atomic Structure calculations
also on atom-atom (van der Waals) dispersion coefficients

Programs

I will get around to publishing some actual code when i get a chance.

Download the (free as in beer and speechi) power-series extrapolation program (spreadsheet) in gnumeric and excel formats. Latest version is 0.95. For a comparison of the different extrapolation methods see mitroy06a.pdf.

Introduction to Antimatter and matter interactions

Overview: The question of whether a positron (the anti-particle of the electron) can form a stable bound state to a neutral atom was first investigated in the early ‘50s.  In 1997 came the breakthrough theoretical confirmation that a positron could bind to lithium was first published by Dr. Mitroy and Dr. Ryzhikh of NTU (and independently by Dr. Strasburger and Prof. Chojnacki in Poland).

They both used a computational algorithm which whilst very accurate for smaller atomic systems, would take months of computer time to even begin to show positive results for larger atoms.  Thus we applied the configuration-interaction (CI) to investigate the structure of atomic systems containing a positron and one or two valence electrons. So far this has resulted in the identification of four new exotic species (ie neutral atoms or ions that can stably bind a positron), positronic calcium, positronic strontium, positronic cadmium and copper positride. The interest of this ‘pure’ research lies in enhancing our understanding of the basic Quantum Physics involved in anti-matter and atom interactions

Some important applications of positrons are:

• Materials analysis using an Anti-matter microscope (ie Scanning Positron Microscope SCM)
• Use of positrons for Oncology in Australia ie Positron Emission Tomography (ie PET scanning). SDSU has a programme in Radiological Health Physics currently as part of our Masters.

For further background and other info see visit the Atomic Physics @ CDU webpages. During August 1998 to August 1999 we were located at the Australian National University in Canberra during Jim's sabbatical there. They now have the Centre for Anti-Matter studies and will hopefully test some of our theories out!