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A spectroscopic determination of e/m

Houston, William V. (1927) A spectroscopic determination of e/m. Physical Review, 30 (5). pp. 608-613. ISSN 0031-899X. doi:10.1103/PhysRev.30.608.

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Rydberg constants for hydrogen and helium.—By an interferometer method the wave-lengths of the hydrogen lines at 6563A and 4861A were measured with reference to λ5015.6750 of He as standard. The values so obtained were, for the doublet at 6563A, 6562.7110±.0018 and 6562.8473±.0009; and for the doublet at 4861, 4861.2800±.0013 and 4861.3578±0022. Similarly the wave-lengths of the 4686 lines of ionized helium were found to be 4685.7030±.0012 and 4685.8030±.0026. From these values of the wave-lengths the Rydberg constant for hydrogen, RH is calculated to be 109,677.759±.008, and the Rydberg constant for helium, RHe, to be 109, 722.403±.004. Calculation of e/m.—The ratio of the mass of the electron to the mass of the hydrogen nucleus, m/mH, is given by m/mH=(RHe-RH)(mHe-m)/RH(mHe-mH)=1.33648(RHe-RH)/RH. The value of e/m is given in terms of the Faraday constant as e/m=(mH/m)(F/mH). If the values of RH and RHe calculated above be substituted in these expressions and if it be assumed that F=96470 abamp. per gr. mol. and mH=1.0072, it is found that e/m has the value (1.7606±.0010)×10^(7) e.m.u. per gr.

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Additional Information:©1927 The American Physical Society. Received 29 July 1927. [W.V.H. was a] National Research Fellow in Physics.
Issue or Number:5
Record Number:CaltechAUTHORS:HOUpr27b
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Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:5654
Deposited By: Tony Diaz
Deposited On:27 Oct 2006
Last Modified:08 Nov 2021 20:27

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