Isotopic Analysis of Carbon and Nitrogen by Means of a 2MV Van de Graaff

The possibilities offered by the nuclear reactions : 12C(p, ¿)13N 14N(p, ¿)15O 13C(p, ¿)14N 15>N(p, ¿)12C to estimate the isotopic concentration ratios 13C/12C, 15N/14N or 15N/12C were studied experimentally. Two kinds of gamma detector /Ge(Li) and NaI(Tl) 7 were used. It is evident that in view of its resolution the former is more discriminating (separation of neighbouring lines), but our results show that the use of a large NaI(Tl) detector is necessary when large batches of samples have to be examined quickly.