Separated isotopic targets of ${\mathrm{Ne}}^{21}$, which were produced at the Nobel Institute of Physics, have been used to measure the $Q$-values of the reactions (1) ${\mathrm{Ne}}^{21}(d,\alpha ){\mathrm{F}}^{19}$, and (2) ${\mathrm{Ne}}^{21}\mathrm{}(d,p)\mathrm{}{\mathrm{Ne}}^{22}$. A double focusing magnetic spectrograph was used to compare the energy of the protons and alpha-particles from these reactions with the alpha-particles from ThC and ThC′. The angle of observation and the deuteron bombarding energy were chosen so that the particles being studied and the alpha-line used for energy calibration lay nearly side by side on the photographic plate used as a detector. The $Q$-values measured are 6.432±0.010 MeV for reaction (1) and 8.137±0.011 Mev for reaction (2). From these $Q$-values and the mass of ${\mathrm{F}}^{19}$ the atomic masses of ${\mathrm{Ne}}^{21}$ and ${\mathrm{Ne}}^{22}$ are obtained. Other alpha-groups from reaction (1) correspond to transitions to states in ${\mathrm{F}}^{19}$ at 0.113±0.008 Mev and 0.192±0.012 Mev above the ground state. Additional particle groups from N and Na contamination on the targets have been observed: The $Q$-values measured are 8.613±0.011 Mev for ${\mathrm{N}}^{14}\mathrm{}(d,p)\mathrm{}{\mathrm{N}}^{15}$ and 4.723±0.008 for ${\mathrm{Na}}^{23}\mathrm{}(d,p)\mathrm{}{\mathrm{Na}}^{24}$.

• Received 15 August 1952

DOI:https://doi.org/10.1103/PhysRev.88.1254