Actinium isotope cross sections for Ra(p,xn) reactions measured at low energies.

Cross sections for production of the medical isotope Ac by the Ra(p,2n) reaction have not previously been measured in fine steps over the relevant energy region, and no measurements are presently available in the literature for the actinium contaminant isotopes created by the adjacent Ra(p,n)Ac and Ra(p,3n)Ac reactions. We report thin-target cross-section measurements for production of Ac and Ac by protons of 15.1-16.8 MeV incident on radium. An upper limit for the Ac cross section is also reported.