IN A (" NaI CRYSTAL (l-a*} ail. ex r . THEORY NEGLECTING r L Lo SECONDARY EFFECTS YY Agg* Area of Photo Peck - 4 J \ 7 S a Ary *Areqg of Total (Photo and Compton) “ ma -—_ i 0.03155 Fig. 3.26 i i i 600 jt tf ik poo ENERGY (KEV) i 2700 Theoretical and Experimental Ratios of the Area of the Photo- peak to Total Area and Fractional Absorption in a lein, NaI Crystal tT rb bity \ TT i l Prreyty f ti pid 1 1 | fi ii q fo tT PHOTO PEAK CORRECTION FACTOR (GAMMA RAYS/VOLT COUNTAMIN) 3 pf er ri4ry T TATE t T 100 i l i i | co ENERGY (KEV) Lod dt $00 1600 Fig. 3.27 Factor to Convert Area of Photopeak in Gamma Rays/Volt Count/min into Number of Gamma Rays/min 81