Tables 657 {concluded) and 658 

 RONTGEN RAYS (X RAYS) 



TABLE 657 {Concluded). 



541 



Emission Lines and Critical Absorption Limits 

 (in Angstroms) 



X a is the wave length of the critical absorption limit associated with the emission lines 

 listed in the same subgroup. The italicized values are observed; other critical absorption 

 limits are computed or interpolated. 



TABLE 658.— Probabilities of Ionization in K and L Shells 



An atom ionized, in the K shell, say, by one of the two processes described, can either 

 (a) radiate a quantum of K characteristic radiation, or it can (b) convert an equivalent 

 amount of energy into an ionization (with photoelectric emission) of its own outer shells 

 L, M, etc. (compound photoelectric effect). The probability {u) of occurrence of process 

 (a) subsequent to the ionization of an atom depends on the atom, and on the particular 

 shell ionized. Some numerical values for the probability u are given in the table below. 



Values in parentheses are comparatively uncertain. 



Element A 

 u .07 



Cr 

 •23 



Fe 



.28 



Co 



(-39) 



Ionization in the K shell 



Ni Cu Zn Se Br Kr 

 .36 .38 .41 .54 .56 (.51) 



Ionization in the L shell 



Sr 

 .62 



Mo 

 .68 



Ag 



(-86) 



I 



(-75) 



Xe 



(.70 



Element Kr Xe 

 u (.13) (.25) 



Smithsonian Tables 



