[1] Victoria Univ Wellington, Fac Sci, Wellington, New Zealand
[2] Inst Geol & Nucl Sci Ltd, Lower Hutt, New Zealand
[3] Massachusetts Gen Hosp, NE Proton Therapy Ctr, Boston, MA 02114 USA
[4] Purdue Univ, PRIME Lab, W Lafayette, IN 47907 USA
[5] Los Alamos Natl Lab, Grp NIS 2, Los Alamos, NM 87545 USA
[6] Univ British Columbia, TRIUMF, Vancouver, BC V6T 2A3, Canada
[7] Univ Calif Davis, Crocker Nucl Lab, Davis, CA 95616 USA