MEASUREMENT OF IONIZING RADIATIONS 



159 



expressions are 



F = D/n'Q(aa + r,„) in terms of the energy absorbed by the medium 

 F = J • Wpm/nl{aa + Ty) in terms of the ionization measured in the 



gas 



F = 



roentgens X 83.4 



which are vahd only for strictly monoergic radiation since (ca -\- t) is a 

 function of quantum energy. The photon flux is obviously 



Nh. = F/hv 



The energy flux F and the photon flux A^;,^, corresponding to an exposure 

 of 1 r, as a function of photon energy are shown in Figs. 2-6 and 2-7, 



001 003 



01 



30 



100 



03 I 3 10 



PHOTON ENERGY, Mev 

 Fig. 2-6. Energy flux per roentgen as a function of photon energy. 



E 

 o 



c 

 o 



X 



3 



O 



I 



a. 



0.1 1.0 10 100 



PHOTON ENERGY, Mev 

 Fig. 2-7, Photon flux per roentgen as a function of photon energy. 



