Published online by Cambridge University Press: 24 October 2008
The method described gives the differential energy distribution curve directly from readings of a galvanometer and a voltmeter. When adjusted, the arrangement is convenient in operation and very good “resolution” can be obtained. The existence of a maximum frequency of secondary electrons at a finite small energy has been established, and its position is shown to be independent of the energy of the primary beam over a fairly wide range. The effect of deposition of tungsten on a clean copper surface is studied with respect to the secondary emission properties of the surface. From these experiments some interesting conclusions concerning the mechanism of the process may be drawn.
I am very grateful to Prof. Sir Ernest Rutherford for the encouragement he has given and the interest he has taken in this work.
* Camb. Phil. Soc. Proc. XXIII, Pt. 5 (1927), p. 523.Google Scholar
* The actual magnitudes of r and R are governed in practice by the relations
where Ȓ is the resistance for critical damping of the galvanometer.
† Becker, . Ann. der Physik, LXXVIII (1925), p. 209.CrossRefGoogle Scholar
* Becker, , Ann. der Physik LXXV (1924), p. 217.CrossRefGoogle Scholar
† Campbell, , Phil. Mag. XXIII (1914), p. 46.Google Scholar
‡ Petry, , Phys. Rev. 1925, p. 346;CrossRefGoogle ScholarFarnsworth, , Phys. Rev. XXVI (1925), p. 41;CrossRefGoogle ScholarBarber, , Phys. Rev. 1921, p. 322.CrossRefGoogle Scholar
* The sharpness of these images showed that the vacuum conditions inside the experimental tube were adequate.