Improved tungsten moderator structures for slow positron beams

L. Liszkay, Z. Kajcsos, M. F. Barthe, L. Henry, G. Duplâtre, A. Nagy

Research output: Contribution to journalArticle

5 Citations (Scopus)

Abstract

Tungsten filaments from commercial incandescent light bulbs have been tested as slow positron moderators. The filaments were annealed by electric current in the neutral gas atmosphere of the bulbs at or above the normal operating temperature of the lamp. The total efficiency of the positron source/moderator assembly was found to be as high as 4 × 10-4. This value is almost doubled at high extraction voltage (3000 V). Neither the annealing temperature (i.e. the heating current) nor the filament thickness (related to the nominal power of the lamp) affected significantly the moderation efficiency, most probably due to the relatively thick filaments used and the difficulties in controlling the source geometry. It is suggested that the moderation efficiency can be further improved by using structures with thinner tungsten patterns, optimised configuration and extraction electric field.

Original languageEnglish
Pages (from-to)16-19
Number of pages4
JournalApplied Surface Science
Volume194
Issue number1-4
DOIs
Publication statusPublished - Jun 21 2002

Fingerprint

Tungsten
moderators
Moderators
Positrons
positrons
filaments
tungsten
luminaires
Electric lamps
Electric currents
bulbs
neutral gases
Gases
operating temperature
electric current
Electric fields
Annealing
Heating
Temperature
Geometry

Keywords

  • Positron annihilation
  • Positron moderator
  • Slow positron beam
  • Tungsten

ASJC Scopus subject areas

  • Physical and Theoretical Chemistry
  • Surfaces, Coatings and Films
  • Condensed Matter Physics

Cite this

Improved tungsten moderator structures for slow positron beams. / Liszkay, L.; Kajcsos, Z.; Barthe, M. F.; Henry, L.; Duplâtre, G.; Nagy, A.

In: Applied Surface Science, Vol. 194, No. 1-4, 21.06.2002, p. 16-19.

Research output: Contribution to journalArticle

Liszkay, L, Kajcsos, Z, Barthe, MF, Henry, L, Duplâtre, G & Nagy, A 2002, 'Improved tungsten moderator structures for slow positron beams', Applied Surface Science, vol. 194, no. 1-4, pp. 16-19. https://doi.org/10.1016/S0169-4332(02)00105-8
Liszkay, L. ; Kajcsos, Z. ; Barthe, M. F. ; Henry, L. ; Duplâtre, G. ; Nagy, A. / Improved tungsten moderator structures for slow positron beams. In: Applied Surface Science. 2002 ; Vol. 194, No. 1-4. pp. 16-19.
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