An Independent Determination of Fixed Points on the High Voltage Scale

Since present methods allow the comparison of high voltages with an accuracy of 0.1 percent, it was felt that a more accurate determination of certain fixed points would be desirable. This work is an attempt to establish more precisely the voltages of several well-known nuclear reactions which have been used as convenient voltage calibration points. The absolute values of the proton energies obtained for the various calibration points are: 1.883 Mev for the $\mathrm{Li}\mathrm{}(p,n)\mathrm{}$ threshold, 2.058 Mev for the $\mathrm{Be}\mathrm{}(p,n)\mathrm{}$ threshold, 0.877 Mev for the first strong $\mathrm{F}(p,\gamma )$ resonance, and 0.4465 for the $\mathrm{Li}(p,\gamma )$ resonance. The absolute values are thought to be accurate to within 0.3 percent and the relative values to about 0.1 percent.