title: A theoretical model for the production of Ac-225 for cancer therapy by neutron capture transmutation of Ra-226.
abstract: Radium needles that were once implanted into tumours as a cancer treatment are now obsolete and constitute a radioactive waste problem, as their half-life is 1600 years. We are investigating the reduction of radium by transmutation by bombarding Ra-226 with high-energy neutrons from a neutron source to produce Ra-225 and hence Ac-225, which can be used as a generator to produce Bi-213 for use in 'Targeted Alpha Therapy' for cancer. This paper examines the possibility of producing Ac-225 by neutron capture using a theoretical model in which neutron energy is convoluted with the corresponding neutron cross sections of Ra-226. The total integrated yield can then be obtained. This study shows that an intense beam of high-energy neutrons could initiate neutron capture on Ra-226 to produce Ra-225 and hence practical amounts of Ac-225 and a useful reduction of Ra-226.
authors.affiliation: Centre for Experimental Radiation Oncology, St George Cancer Care Centre, Gray Street, Kogarah, NSW, Australia. gmel@tpg.com.au
authors.forename: G
authors.initials: G
authors.lastname: Melville
authors.forename: P
authors.initials: P
authors.lastname: Melville