Measurement of Lenard Rays

Abstract

HomeRadiologyVol. 17, No. 4 PreviousNext ArticlesMeasurement of Lenard RaysLauriston S. TaylorLauriston S. TaylorLauriston S. TaylorPublished Online:Oct 1 1931https://doi.org/10.1148/17.4.736MoreSectionsPDF ToolsImage ViewerAdd to favoritesCiteTrack CitationsPermissionsReprints ShareShare onFacebookTwitterLinked In Abstract—An investigation is described in which the correct measurement of the electron output—Lenard current—from high voltage cathode-ray or Lenard-ray tubes is attempted.The evidence presented shows that a Faraday chamber of proper dimensions may be used to measure the Lenard-ray current which at any point is shown to be a linear function of the total tube current. The open-plate method of measuring Lenard currents yields results which are consistently too low, although under the conditions here used they bear a constant relationship to the Faraday chamber measurements. The open-plate measurements are, therefore, also a linear function of the total tube current. The condenser method of measurement (Thaller) yields measurements above or below those of the Faraday chamber, depending upon the relationship of the atomic numbers of the two plates. Moreover, the current measured by this method is not a linear function of the total tube current and hence does not bear a constant relationship to the Faraday chamber measurements under the conditions used. Measurements of the range of scattered electrons from Lenard tubes operating at about 160 K.V. peak, indicate a maximum of about 15 mm. in air, which is equivalent to an energy of about 60 electron kilovolts. By means of a variable Faraday chamber described, it is possible to obtain a measure of the velocity distribution of the scattered electrons.Article HistoryPublished in print: Oct 1931 FiguresReferencesRelatedDetailsRecommended Articles RSNA Education Exhibits RSNA Case Collection Vol. 17, No. 4 Metrics Altmetric Score PDF download