274 Dr. L. Vegard on the X-Ray Spectra 



these corrections are due to errors which enter into the 

 energy, the correction terms o£ the frequency cannot essen- 

 tially alter the values which the various hypotheses give for 

 the deviation from Kossel's relation. Thus the assumption I. a 

 makes d identically equal to zero independent of the special 

 form of the energy function. And the assumption II., 

 which is merely a slight modification of I., will make d 

 approximately equal to zero. 



Thus, so long as we build on the scheme here proposed for 

 the production of X-rays, I can see no escape from assump- 

 tion I/I.a, that recombination takes place from secondary circles 

 (systems) arid that always the angular momentum of the elec- 

 trons left behind in the atom is kept constant during expulsion 

 and recombination. 



If the change of energy of the electronic systems outside 

 the broken ring which accompanies the ionization process 

 does not escape in the form of radiation, but is utilized 

 for the motion of the escaping electron, we found the 

 frequency of the absorption edge by putting t = co in the fre- 

 quency formula corresponding to III. a. And it was found 

 that the agreement between the calculated and observed 

 values was very good indeed. 



The form here given to the hypothesis of recombination 

 from secondaries will not only explain the principal (a) lines, 

 but will also give a very close agreement for the second 

 (/3) lines of the K- and L-series. If we further assume that 

 the L-ring has one circular and one elliptic state we may 

 say that the following lines have been explained : K a , Kp, 

 the doublets of the L-series (a, /3), (7, h) (Sommerf eld's 

 denotation), and, finally, M a « 



An explanation of the /-series, such as the one given in 

 Paper I. by means of two L-rings, is not consistent with the 

 hypothesis of recombination from secondaries in its modified 

 form ; but we shall have to find some other explanation of 

 this series of lines. 



The line ~Kp 2 of Siegbahn is no doubt produced by recom- 

 bination from a secondary for which t = 4 and ought to be 

 denoted by K y . Also in the case of the L- and M-radiation 

 some of the lines here left out are merely to be considered as 

 members of the series corresponding to higher values of t. 



The modified form of the hypothesis of recombination 

 from secondaries leads to the following constitution of the 

 electronic systems nearest to the nucleus : — 



1 K-system with quant-number 1 consisting of 3 electrons. 

 1 » >> j> » » 2 „ „ / „ 



1 M- „ „ „ „ 3 „ „ 12 



