NuclidesAr42andCl39

The masses of ${\mathrm{Cl}}^{39}$ and ${\mathrm{Ar}}^{42}$ and the energies of their first excited states have been determined by an investigation of the reactions ${\mathrm{Ar}}^{40}(t, \alpha ){\mathrm{Cl}}^{39}$ and ${\mathrm{Ar}}^{40}(t, p){\mathrm{Ar}}^{42}$. Charged reaction products were analyzed with a high-resolution magnetic spectrometer. The experimental results for ${\mathrm{Ar}}^{42}$ are: mass excess $\mathrm{}(M-A)=-34.423\mathrm{}\pm 0.040$ Mev (${\mathrm{C}}^{12}$=0) or -21.990±0.040 Mev (${\mathrm{O}}^{16}$=0); energy of first excited state = 1.138±0.030 Mev. The experimental results for ${\mathrm{Cl}}^{39}$ are: mass excess $\mathrm{}(M-A)=-29.772\mathrm{}\pm 0.040$ Mev (${\mathrm{C}}^{12}$=0) or -18.227 ±0.040 Mev (${\mathrm{O}}^{16}$=0); energy of first excited state = 0.364±0.030 Mev. The $Q$ values of ${\mathrm{Ar}}^{40}(t, p){\mathrm{Ar}}^{42}$ and ${\mathrm{Ar}}^{40}(t, \alpha ){\mathrm{Cl}}^{39}$ were found to be 7.046±0.040 and 7.259±0.040 Mev, respectively.