| Popis: |
A mixture of ${\mathrm{N}}^{14}$ and ${\mathrm{N}}^{15}$ gas has been bombarded with deuterons of 1 Mev and the disintegration particles observed at right angles to the direction of the deuteron beam. The ranges of the disintegration particles were measured by means of a shallow ionization chamber and pulse amplifier. The shortest measurable range was 2.1 cm (15\ifmmode^\circ\else\textdegree\fi{}C, 760 mm Hg). The reaction ${\mathrm{N}}^{15}(d,\ensuremath{\alpha}){\mathrm{C}}^{13}$ gave rise to one group of alpha-particles at 5.25 cm range with a $Q$ value of 7.54 Mev. Three groups of alpha-particles (11.97 cm, 6.54 cm and 3.47 cm range) were observed arising from the reaction ${\mathrm{N}}^{14}(d,\ensuremath{\alpha}){\mathrm{C}}^{12}$. The $Q$ values corresponding to these three groups are 13.39 Mev, 9.02 Mev and 5.77 Mev, respectively. From the reaction ${\mathrm{N}}^{14}(d,p){\mathrm{N}}^{15}$ two valid groups of protons were observed having ranges of 90.5 cm and 21.02 cm with $Q$ values of 8.51 Mev and 3.15 Mev. The ranges given above are from a single measurement and the $Q$ values are the average of the results of several measurements. A group at 66 cm previously reported due to this reaction was found to be due to boron contamination. No proton groups were found which could be attributed to the reaction ${\mathrm{N}}^{15}(d,p){\mathrm{N}}^{16}$, although a radioactivity of half-life 9.5\ifmmode\pm\else\textpm\fi{}1.0 sec. was found to result from deuteron bombardment of the mixture of ${\mathrm{N}}^{14}$ and ${\mathrm{N}}^{15}$. This radioactivity was not found when ${\mathrm{N}}^{14}$ alone was bombarded. A method of range measurement is described which allows accurate corrections to be made for the effect of chamber depth and of the bias on the grid of the counting thyratron on the output of the pulse amplifier. |
