PREPARATION OF MANGANESE-53

The nuclide53Mn was produced by the following three nuclear reactions,52Cr(d, n)53Mn,51V(3He n)53Mn and50Cr(α, n), (α, p)53Mn. Enriched52Cr and50Cr metal targets were prepared on copper plate holder by electrodeposition. The commercially available natural vanadium foil was used for the51V(3He, n)53Mn reaction. Each target was bombarded in a cyclotron. Manganese was extracted and purified without using carrier from the bombarded targets by anion and cation exchanges and solvent extraction. The isotopic ratio53Mn/55Mn was measured by mass spectrometry and the amount of55Mn was determined by neutron activation analysis. The activity of53Mn obtained was 7 dpm by 750 millicoulombs in3He bombardment (E3He=20 MeV). The activity due to by-product54Mn was about several thousands times higher than that of53Mn in3He and deuteron bombardments, which were produced through51V(3He, γ)54Mn and53Cr(d, n)54Mn. In alpha bombardment (Eα=15 MeV), the activity of53Mn produced was 8 dpm by 95 millicoulombs. The activity ratio, dpm54Mn/dpm53Mn, was about 3, and this ratio was the best one among the results so far obtained.