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On the scattering of fast neutrons by protons*

Published online by Cambridge University Press:  24 October 2008

A. Pais
A. Pais
Affiliation:
Instituut voor Theoretische NatuurkundeRijks-Universiteit, Utrecht
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Extract

1. Introduction. Recent experiments by Amaldi and his collaborators on the scattering of high-energy neutrons (of 10–15 MeV.) by protons(2) have disclosed a considerable anisotropy in the angular distribution of the scattered particles. Theoretical discussions of this problem show an interesting feature in that the results depend sensitively on the basic assumptions involved with regard to the charge dependence of the neutron-proton interaction. This can be seen in particular from calculations by Rarita and Schwinger(3) and by Ferretti(4). The former authors started from the assumption of a distance dependence of this interaction represented by a square well, while the angular and spin dependence included terms of the axial dipole type. If the charge dependence was further assumed to be of the ‘symmetrical’ type, they found a value for the anisotropy in strong disagreement with experiment, whereas the total cross-section agreed with the measured value; a ‘neutral’ theory, on the other hand, yielded agreement as regards anisotropy, but a total cross-section too large by a factor of the order of 1·5. Ferretti investigated the scattering on Bethe's neutral meson theory(5) and found satisfactory agreement with regard to both angular distribution and total cross-section. It should be stressed that all calculations mentioned were performed in the approximation in which only the contributions of the S- and P-waves are considered.

Type
Research Article
Information
Mathematical Proceedings of the Cambridge Philosophical Society , Volume 42 , Issue 1 , February 1946 , pp. 45 - 54
Copyright
Copyright © Cambridge Philosophical Society 1946

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References

REFERENCES

(1)Hulthén, L.Fysiogr. Sällsk. Lund Förhandl. 14 (1944), no. 21.Google Scholar
(2)Amaldi, E., Bocciarelli, D., Ferretti, B. and Trabacchi, G.Naturwissenschaften, 48 (1942), 39.Google Scholar
(3)Rarita, W., Schwinger, J. and Nye, H. A.Phys. Rev. 59 (1941), 201.Google Scholar
Rarita, W. and Schwinger, J.Phys. Rev. 59 (1941), 436.CrossRefGoogle Scholar
(4)Ferretti, B.Ric. Sci. (1941), 843, 993.Google Scholar
(5)Bethe, H. A.Phys. Rev. 57 (1940), 260, 390.CrossRefGoogle Scholar
(6)Møller, C. and Rosenfeld, L.Det Kgl. Danske Vid. Selsk. Mat. Fys. Medd. 17 (1940), 8.Google Scholar
(7)Ferretti, B.Il Nuovo Cim. 1 (1943), 25.CrossRefGoogle Scholar
(8)Hulthén, L.Ark. Mat. Astr. och Fys. 29 A (1943), no. 33; 30 A (1943), no. 9.Google Scholar
(9)Watson, G. N.Theory of Bessel functions (Cambridge 1922), p. 403.Google Scholar
(10)See reference (9), p. 389.Google Scholar
(11)Cf. Whittaker, E. T. and Watson, G. N.Modern analysis, 4th ed. (Cambridge 1935), pp. 299 (Ex. 18) and 317.Google Scholar
(12)Salant, E. and Ramsey, N.Phys. Rev. 57 (1940), 1075.Google Scholar
Ageno, M., Amaldi, E., Bocciarelli, D. and Trabacchi, G.Il Nuovo Cim. 1 (1943), 253.CrossRefGoogle Scholar