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The β-ray Type of Disintegration

Published online by Cambridge University Press:  24 October 2008

C. D. Ellis  and
W. A. Wooster
C. D. Ellis
Affiliation:
Trinity College
W. A. Wooster
Affiliation:
Peterhouse
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Extract

In three other papers in this number of the Proceedings will be found direct experimental evidence that in a β-ray disintegration the γ-rays are emitted after the electron has been ejected from the nucleus. In this paper we discuss this result in more detail and especially its bearing on the general picture of the β-ray disintegration.

Type
Research Article
Information
Mathematical Proceedings of the Cambridge Philosophical Society , Volume 22 , Issue 6 , November 1925 , pp. 849 - 860
Copyright
Copyright © Cambridge Philosophical Society 1925

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References

* Meitner, , Naturwissenschaft, Bd. III, p. 160, 1924.Google Scholar

† Smekal, , Zeit. f. Physik, Bd. 28, p. 142, 1924.CrossRefGoogle Scholar

‡ Ellis, and Skinner, , Proc. Roy. Soc. A, vol. cv, p. 177.Google Scholar

* Ellis, and Skinner, , loc. cit. p. 173.Google Scholar

† Ellis, and Skinner, , Proc. Roy. Soc. A, vol. cv, p. 191, 1924.Google Scholar

‡ Black, , Proc. Roy. Soc. A, vol. cv, p. 633, 1924.Google Scholar

* We regard these level systems as showing the transitions that occur when a normal radium B or C nucleus is ionised. Except for small corrections in the energy they will also show the structure of the normal radium B nucleus.Google Scholar

* The emission of the γ-rays has been discussed several times both by Meitner and Ellis since the first evidence of quantum states in the nucleus was obtained (Ellis, , Proc. Roy. Soc. A, vol. CI, p. 1,1922), but whereas Ellis endeavoured to combine this with emission before the disintegration Meitner adopted the view which has now been proved to be correct. The difference between the points of view was otherwise small, but we would emphasise that the credit of first giving a generally acceptable account of the emission of γ-rays is Meitner's and therefore, in respect of priority, our present hypothesis is to be regarded as a possible extension of Meitner's standpoint. It will be noticed that we lay stress on the similarity of the electronic systems in the successive nuclei of the same radioactive family and in general seek to interpret results in terms of level systems. Meitner, keeping to a more general standpoint, has not attempted any detailed treatment, and in fact does not refer to level systems at all. (See Meitner, infra.)CrossRefGoogle Scholar

† Meitner, , Zeit. f. Physik, xxvi, p. 169, 1924, and Naturwissenschaft, loc. cit.CrossRefGoogle Scholar

‡ Ellis, , Camb. Phil. Soc. Proc. vol. xxii, p. 376, 1924.Google Scholar

* Meitner has expressed the view that the extent of the γ-ray spectrum depends on the “deepness” of the ionisation, but has refrained from making the further extensions which we propose, and does not believe that the γ-rays give direct information about the stationary states in the nucleus.Google Scholar

† This would probably involve the existence of two maximum velocities for the disintegration electrons, but it can easily be seen that no very marked effect would be produced on the form of the continuous spectrum owing to the peculiar shape of this curve. In the α-ray case where the particles all have the same velocity the effect would be very obvious, and this may be the interpretation of the occasional long range particles found.Google Scholar

* Meitner, , Zeit. f. Physik, 19, p. 307, 1923.CrossRefGoogle Scholar

† Emeléus, , Camb. Phil. Soc. Proc. vol. xxii, p. 400, 1924.CrossRefGoogle Scholar

‡ A great deal of the argument that follows depends on the general form of the radium E continuous spectrum. This we have obtained from some unpublished measurements of Madgwick made in the Cavendish Laboratory, from Kovarik, and McKeehan, (Phys. Rev. vol. VIII, p. 574, 1925) and fromGoogle ScholarSchmidt, (Phys. Zeit. 8, p. 361, 1907).Google Scholar

* Loc. cit.Google Scholar

* We are engaged in making this measurement at present, but it will probably be some time before we obtain definite values as only small sources are available with correspondingly small heating effects.Google Scholar