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A Type of Geiger-Müller Counter Suitable for the Measurement of Diffracted Mo K X-Rays*
Published online by Cambridge University Press: 10 January 2013
Extract
The design and construction of Geiger-Müller counters which will respond reliably to Mo K x-rays is described. The impulses are amplified and recorded mechanically with the aid of a thyratron circuit. The amplifying and counting circuit, and the counting mechanism, are also described. The time of recovery of the counters has been determined by the use of an oscillograph and found to be less than 0.001 sec. when the proper values are used for the resistance and capacitance of the counter circuit. It is shown that for counting rates up to 600 per minute there is less than a 1 percent correction due to the fact that the impulses are random in nature. Several fundamental tests are described, which have been applied to the counter and the circuit. These tests have shown the counter and the circuit to be a reliable method of measuring x-ray intensities. Graphs are shown of the diffraction patterns of NaCl and KC1 taken by means of the counters. These graphs duplicate the well-known diffraction patterns of these materials, thus giving additional evidence of the reliability of the counters.
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- Copyright © Cambridge University Press 1991
References
1 Johnson, A., Zeits. f. Physik 36, 426 (1926)CrossRefGoogle Scholar.
2 Van den Akker, J.A., Rev. Sci. Inst. 1, 672 (1930)CrossRefGoogle Scholar.
3 Curtiss, I. F., Bur. Standards J. Research 5, 115 (1930)CrossRefGoogle Scholar.
4 Van den Akker, J. A. and Wilson, E.C., Phys. Rev. 37, 1631 (1931)CrossRefGoogle Scholar.
5 Juppertsberg, A., Zeits. f. Physik 75, 231 (1932)CrossRefGoogle Scholar.
6 Locher, G.L., Phys. Rev. 42, 525 (1932)CrossRefGoogle Scholar.
7 Locher, G.L. and LeGalley, Donald P., Phys. Rev. 46, 1047 (1934)CrossRefGoogle Scholar. The above references are only given as typical examples. They by no means exhaust the list.
8 Street, and Johnson, , Frank, J.. Inst. 214, 155 (1932)Google Scholar.
9 Wynn-Williams, , Proc. Roy Soc. A136, 312 (1932)CrossRefGoogle Scholar.
10 Locher, G.L., J. Frank. Inst. 216, 553 (1933)CrossRefGoogle Scholar.
page 8 note * The size of the residual count will depend, of course, chiefly on the dimensions of the counter. For the counter described here the residual count was 6.66±0.06 per minute.
page 128 note * See Loeb, , Kinetic Theory of Gases, p. 49Google Scholar.
11 Werner, S., Zeits. f. Physik 90, 384 (1934)CrossRefGoogle Scholar; 92, 705 (1935). +NaCl gives certain very weak diffracted beams such as the ones from the (1 1 1, (3 1 1), and (3 3 1) planes, whose intensities depend upon the difference in the diffracting powers of the Na + and Cl−. The rate of counting for such beams is so low that it would have required much more than 240 seconds to obtain a reading free from the effect of the random time distribution of the counts. The beam from the (1 1 1) planes would be diffracted at an angle of 2θ, of about 12.5°. No readings were taken between 12° and 13°. The beam from the (3 1 1) planes corresponds to a small hump at about 24°. The height of this hump above the general background of scattered radiation is certainly considerably in error due to the short time of counting.
12 Compton, A.H., X-Rays and Electrons, p. 126Google Scholar, or Davey, W.P., A Study of Crystal Structure and Its Applications, p. 292Google Scholar.