Hostname: page-component-cd9895bd7-gvvz8 Total loading time: 0 Render date: 2024-12-28T14:27:29.710Z Has data issue: false hasContentIssue false

The interpretation of ionization measurements in gases at high pressures

Published online by Cambridge University Press:  24 October 2008

Elizabeth Kara-Michailova
Affiliation:
Cavendish LaboratoryCambridge
D. E. Lea
Affiliation:
Strangeways LaboratoryCambridge

Extract

When γ-radiation passes through a gas it ionizes by means of fast electrons which produce clusters of secondary ionization at intervals along their paths. At high pressures a considerable amount of recombination of ions takes place in these clusters; in the present paper a theory is described which enables the proportion of ions escaping recombination to be calculated as a function of the gas pressure and collecting field. A review of the available experimental data concerning the variation of ionization current with pressure and collecting field is given, and it is shown that the predictions of the cluster recombination theory are in satisfactory agreement with these experimental data.

Jaffé has given a theory of initial recombination valid for a columnar distribution of ionization, and has shown that this theory is in agreement with experiments in which α-particles produce the ionization. A number of authors have applied Jaffé's equations to ionization produced by fast electrons regardless of the initial localization of the ions in clusters. It is shown in the present paper that such measure of agreement with experiment as is obtained by this procedure is only obtained at the expense of assigning incorrect values to certain known constants. Also in the case of X- and γ-rays the columnar theory predicts a variation of the proportion of recombination with the wave-length of the radiation which is much too rapid. It is further shown that the method based on Jaffé's equations which is used by Clay and his colleagues to extrapolate experimental ionization currents at finite collecting fields to saturation currents at infinite fields is liable to systematic error in a direction likely to lead to the deduction of a spurious wall effect or the exaggeration of an existing wall effect.

Type
Research Article
Copyright
Copyright © Cambridge Philosophical Society 1940

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

(1)Bloch, S.Ann. Phys., Lpz., 38 (1912), 559.CrossRefGoogle Scholar
(2)Bonner, T. W.Phys. Rev. 43 (1934), 871.CrossRefGoogle Scholar
(3)Bowen, J. S.Phys. Rev. 41 (1932), 24.CrossRefGoogle Scholar
(4)Bradbury, N. E.Phys. Rev. 44 (1933), 883.CrossRefGoogle Scholar
(5)Broxon, J. W. and Meredith, G. T.Phys. Rev. 54 (1938), 1, 9, 605.Google Scholar
(6)Broxon, J. W. and Meredith, G. T.Phys. Rev. 55 (1939), 883.CrossRefGoogle Scholar
(7)Buchmann, E.Ann. Phys., Lpz., 87 (1928), 509.CrossRefGoogle Scholar
(8)Chylinski, S.Phys. Rev. 45 (1934), 309.CrossRefGoogle Scholar
(9)Clay, J. and van Tijn, M. V.Physica, 2 (1935), 825.CrossRefGoogle Scholar
(10)Clay, J. and Kwieser, M.Physica, 5 (1938), 725.CrossRefGoogle Scholar
(11)Clay, J. and van Kleef, J.Physica, 4 (1937), 651.CrossRefGoogle Scholar
(12)Clay, J.Proc. Akad. Wet. Amsterdam, 40 (1937), 1.Google Scholar
(13)Cox, E. F.Phys. Rev. 45 (1934), 503.CrossRefGoogle Scholar
(14)Erikson, H. A.Phys. Rev. 27 (1908), 773.Google Scholar
(15)Florance, D. C. H.Phil. Mag. 25 (1913), 172.CrossRefGoogle Scholar
(16)Harig, G.Phys. Z. Sowjet. 5 (1934), 637.Google Scholar
(17)Jaffé, G.Ann. Phys., Lpz., 42 (1913), 303.CrossRefGoogle Scholar
(18)Jaffé, G.Ann. Phys., Lpz., 43 (1914), 249.CrossRefGoogle Scholar
(19)Jaffé, G.Phys. Z. 30 (1929), 849.Google Scholar
(20)Kipphahn, E.Ann. Phys., Lpz., 12 (1932), 401.CrossRefGoogle Scholar
(21)Klemperer, O.Einführung in die Elektronik (Berlin, 1933).CrossRefGoogle Scholar
(22)Klemperer, O.Z. Phys. 45 (1927), 225.CrossRefGoogle Scholar
(23)Kraus, P.Ann. Phys., Lpz., 29 (1937), 449.CrossRefGoogle Scholar
(24)Laby, T. H. and Kaye, G. W. C.Phil. Mag. 16 (1908), 879.CrossRefGoogle Scholar
(25)Landolt-Börnstein, . Tabellen, 5th ed. (Berlin, 19281936).Google Scholar
(26)Langevin, P.Ann. Chim. Phys. (7) 28 (1903), 433.Google Scholar
(27)Lea, D. E.Proc. Cambridge Phil. Soc. 30 (1934), 80.CrossRefGoogle Scholar
(28)Lenard, P.Quantit. u. Kathodenstrahlen (1925).Google Scholar
(29)Lenard, P. and Becker, A.Handb. der Exp. Phys. 14 (1927), 250.Google Scholar
(30)Loeb, L. B.Kinetic theory of gases (New York, 1934).Google Scholar
(31)Mächler, W.Z. Phys. 104 (1936), 1.CrossRefGoogle Scholar
(32)Otto, J.Handb. der Exp. Phys. 8 (I)(1929).Google Scholar
(33)Przibram, K.Handb. der Exp. Phys. 22 (1932).Google Scholar
(34)Sayers, J.Proc. Roy. Soc. A, 169 (1938), 83.Google Scholar
(35)Sievert, R. M.Nature, Lond., 129 (1932), 792.CrossRefGoogle Scholar
(36)Skramstrad, H. K. and Loughridge, D. L.Phys. Rev. 50 (1936), 677.CrossRefGoogle Scholar
(37)Taylor, L. S.Bur. Stand. J. Res. 17 (1936), 983.Google Scholar
(38)Taylor, L. S.Radiology, 29 (1937), 323.CrossRefGoogle Scholar
(39)Thomson, J. J.Conduction of electricity through gases (Cambridge, 1933),Google Scholar
(40)Williams, E. J. and Terroux, F. R.Proc. Roy. Soc. A, 126 (1929), 289.Google Scholar
(41)Wilson, W.Proc. Roy. Soc. A, 85 (1911), 240.Google Scholar
(42)Wilson, C. T. R.Proc. Roy. Soc. A, 104 (1923), 1, 192.Google Scholar
(43)Zanstra, H.Physica, 2 (1935), 817.CrossRefGoogle Scholar