A wide band electron spectrum analyzer

M. Komma  Komma, M. 1978

Nuclear Instruments and Methods, vol. 154, issue 2, pp. 271-277
DOI: 10.1016/0029-554X(78)90410-X
Physikalisches Institut der Universität Tübingen, 7400, Tübingen, Germany

Abstract An optimization procedure for the design of an electron spectrum analyzer (ELSA), which consists of the combination of a triple focusing magnet with an energy sensitive detector was developed. The resulting magnet focuses a solid angle of 7.6 msr (5° × 5°) and a momentum band of Δp/p = 490% (p_max/p_min = 5.9) into a circle with less than 10 mm diameter, so that small SB-detectors with correspondingly good resolution can be applied. Since ELSA can observe electrons within a wide energy band (e.g. 10–275 keV) and with very low background, it may be a helpful device in scattering experiments such as (e, 2e), (e, eγ) and (e, 2eγ) as well as for conversiom electron measurements.

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Doubly differential cross section for K-shell ionisation of silver and gold for 300 KeV electron impact

M Komma et al 1979 J. Phys. B: At. Mol. Phys. 12 L587-L589   doi: 10.1088/0022-3700/12/18/011 
M Komma and W Nakel
Phys. Inst., Univ. Tubingen, Tubingen, West Germany

Abstract The doubly differential K ionisation cross section of Ag and Au was measured for electron impact as a function of outgoing electron energy at a fixed scattering angle of 20 degrees . The incident electron energy was 300 keV. Coincidences between characteristic K X-rays and outgoing electrons are used to isolate the K ionisation process. The results are compared with calculations of Das (1972) and of Das and Konar (1974).

Print publication: Issue 18 (28 September 1979)

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Two-parameter coincidence measurements of bremsstrahlung, electron-electron bremsstrahlung, and K-shell ionisation for 300 keV electron impact

M Komma et al 1982 J. Phys. B: At. Mol. Phys. 15 1433-1441   doi: 10.1088/0022-3700/15/9/018 
M Komma and W Nakel
Phys. Inst., Univ. Tubingen, Tubingen, West Germany

Abstract An electron beam of 300 keV was directed on to thin target foils (C, Cu, Ag, and Au) to investigate the processes of electron-nucleus bremsstrahlung, electron-electron bremsstrahlung and K-shell ionisation. Using a two-parameter arrangement the outgoing electrons from all these processes were detected in coincidence with the emitted bremsstrahlung and K X-ray photons, respectively, as a function of electron and photon energies for fixed detector angles. So it was possible to measure the triply differential cross sections of the processes of electron-nucleus bremsstrahlung and electron-electron bremsstrahlung and the doubly differential cross section of K-shell ionisation simultaneously. A comparison with theoretical calculations is given.
Print publication: Issue 9 (14 May 1982)

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Modellversuche zur Beugung von Röntgenstrahlen
Eine Unterrichtseinheit in Kl. 13  

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