Activation Cross Sections of Calcium, Potassium, and Aluminum for 14.2-MeV Neutrons

The cross sections for some ($n, t$), ($n, d$), ($n, p$), ($n, \alpha$), and ($n, 2n$) reactions have been measured on the various enriched isotopes of calcium and spectroscopically pure potassium and aluminum. Powdered samples, wrapped in thin aluminum foils to act as neutron monitors, were irradiated with 14.2±0.2 MeV neutrons. The induced absolute activities were measured by a calibrated and specially shielded well-type NaI(Tl) crystal. The following results (in millibarns) for the cross sections have been obtained: ${\mathrm{Al}}^{27}(n, p){\mathrm{Mg}}^{27}$, 71±9; ${\mathrm{Ca}}^{40}(n, t){\mathrm{K}}^{38}$ (ground state), 0.18±.02; ${\mathrm{Ca}}^{42}(n, p){\mathrm{K}}^{42}$, 190±24; ${\mathrm{Ca}}^{43}(n, p){\mathrm{K}}^{43}$, 93±12; ${\mathrm{Ca}}^{43}(n, d){\mathrm{K}}^{42}$, 1.3;${\mathrm{Ca}}^{44}(n, p){\mathrm{K}}^{44}$, 20±8; ${\mathrm{Ca}}^{44}(n, \alpha ){\mathrm{Ar}}^{41}$, 35±3; ${\mathrm{Ca}}^{44}(n, d){\mathrm{K}}^{43}$, 2.6±.4; ${\mathrm{Ca}}^{48}(n, 2n){\mathrm{Ca}}^{47}$, 900±108; ${\mathrm{K}}^{39}(n, 2n){\mathrm{K}}^{38}$ (ground state),2.6±.4; ${\mathrm{K}}^{41}(n, p){\mathrm{Ar}}^{41}$, 50±6; ${\mathrm{K}}^{41}(n, \alpha ){\mathrm{Cl}}^{38}$, 46±6. The cross sections for the ${\mathrm{Ca}}^{43}(n, d){\mathrm{K}}^{42}$ and ${\mathrm{Ca}}^{44}(n, d){\mathrm{K}}^{43}$ reactions are reported for the first time. Other cross sections measured in this work are compared with their earlier values.