a 127 ee 4s that of course the line isn't straight up here as it is down here, so with very low activity semples you ¢*n run just a few absorbers beginning with a curve and determine the maximum energy. The next slide is a two component system and mathematically of course, two Beta Emitters will be eimply the sum of two straight lines and when you run the total semple, you get the cumulative curve, extrae- polating that and cubtracting your total curve, you obtain these two straight lines. We have ordered isotopes from Oak Ridge and run in the order of a hundred of them, and plotted each one separately to de- termine the slore: of these lanes and then plotted the slope against the known maxinua energy. . ¥ t The next slide is this relationship, This fe our ecralculated slope versus the maximum energy of the sample which you see over here for just a few of the isotopes, You can see there's a good empirical relationship, Can we have the lights, please? =e /Q