THE USE OF ACCELERATORS OF CHARGED PARTICLES 



407 



In the tube shown in Fig. 5 there are two chambers (6 and 7) with different 

 concentrations of gas in them. The necessary difference of pressure between 

 the two chambers is maintained by the device 5, which is an ion pump with 

 a cathode which does not absorb the ionized gas. Experimentation with an 

 ion pump of this type has shown that with a relatively small expenditure 

 of effective power it can ensure a pressure difference of 10"^ to 10~^ mm Hg C^). 



Table 2. Expenditure of deuterium in the acceleration tube 



Figure 6 shows an interesting variety of sealed acceleration tube in which 

 a single device performs the functions of an ion pump and an ion source 

 for the acceleration tube. 



In Table 2 there are presented the results of an estimate of expenditure 



r 



3 



— + 



Fig. 6. A basic construction scheme of a sealed acceleration tube in which the ion 



pump 5 also serves as an ion source. IV — power source of the ion pump; other notations 



are the same as in Figs. 4 and 5. 



