Accession Number : AD0832446

Title :   ELECTRON IONIZATION CROSS SECTIONS.

Descriptive Note : Quarterly technical management rept. no. 3,

Corporate Author : MASSACHUSETTS INST OF TECH CAMBRIDGE PARTICLE OPTICS LAB

Personal Author(s) : Brody, M. D. ; Wang, K. L. ; Crawford, C. K.

Report Date : APR 1968

Pagination or Media Count : 13

Abstract : Discussion of the Exponential Depletion Method continues. The electron collector at the depletion region is considered, and a method of measuring the integral of (phi ds) is proposed, which takes into account some non-uniformity in the bombarding electron current density. The previous modulating ionizer design is compared with two subsequent designs of the depletion region ionizer. Both new designs were constructed, but only the second yielded good results. It can produce a modulation coefficient of up to xi = 0.00275 versus xi = 0.00085 for the old modulating ionizer. However, operation of the ionizer at this level of performance produces instabilities caused by non-uniform thermal expansions due to large temperature gradients, and the operation becomes erratic when pushed to the upper limit of xi = 0.00275. (Author)

Descriptors :   *IONIZATION), (*ELECTRON IRRADIATION, ELECTRON BEAMS, ELECTRON GUNS, MOLECULAR BEAMS, IONIZATION CHAMBERS, MODULATION, PERFORMANCE(ENGINEERING), ION SOURCES.

Subject Categories : Physical Chemistry
      Particle Accelerators
      Nuclear Physics & Elementary Particle Physics

Distribution Statement : APPROVED FOR PUBLIC RELEASE