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Applied physics

, Volume 23, Issue 2, pp 189–191 | Cite as

Brightness enhancement of slow positron beams

  • A. P. MillsJr.
Solids and Surfaces

Abstract

The brightness of slow positron beams can be enhanced significantly by repeated stages of moderation, acceleration and focusing. Presently available data suggest that the source spot area should decrease by 10−4 after each stage with only a modest loss of intensity. Beams with very small angular divergence, which could be made with this technique, would be useful for characterizing surfaces by positron diffraction and microscopy. Using such beams it is possible to envision the study of new exotic systems such as thee +-e plasma and the positronium molecule.

PACS

78.70 79.20 

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References

  1. 1.
    T.S.Stein, W.E.Kauppila, V.Pol, J.H.Smart, G.Jesion: Phys. Rev. A17, 1600 (1978), and references thereinCrossRefADSGoogle Scholar
  2. 2.
    For a recent review see S.Berko, K.F.Canter, A.P.Mills, Jr.: InProgress in Atomic Spectroscopy Part B, ed. by W.Hanle and H.Kleinpoppen (Plenum Press, New York 1979) p. 1427Google Scholar
  3. 3.
    See, for example, A.P.Mills, Jr., P.M.Platzman, B.L.Brown: Phys. Rev. Lett.41, 1076 (1978)CrossRefADSGoogle Scholar
  4. 4.
    I.J.Rosenberg, A.H.Weiss, K.F.Canter: Phys. Rev. Lett.44, 1139 (1980); A.P.Mills, Jr., P.M.Platzman: To be publishedCrossRefADSGoogle Scholar
  5. 5.
    A.P.Mills, Jr.: Appl. Phys. Lett.35, 427 (1979)CrossRefADSGoogle Scholar
  6. 6.
    A.P.Mills, Jr.: Phys. Rev. Lett.41, 1828 (1979)CrossRefADSMathSciNetGoogle Scholar
  7. 7.
    The use of non-conservative forces to overcome the limitations of Liouville's theorem has found application in light collection from scintillators by wavelength shifting light pipes. [W.A.Schurcliff: J. Opt. Soc. Am.41, 209 (1951); R.L.Garwin: Rev. Sci. Instrum.31, 1010 (1960).] A similar technique for electrons could make use of negative electron affinity GaAs (CsO) surfaces. If a suitable moderator for ultracold neutrons [14] can be found, this would be another field which could benefit from brightness enhancementGoogle Scholar
  8. 8.
    R.L.Palmer, J.N.Smith, H.Saltsburg, D.R.O'Keefe: J. Chem. Phys.53, 1666 (1970)CrossRefGoogle Scholar
  9. 9.
    K.G.Lynn: Private communicationGoogle Scholar
  10. 10.
    T.S.Stein, W.E. Kauppila, L.O.Roelling: Phys. Lett.51A, 327 (1975)CrossRefGoogle Scholar
  11. 11.
    D.G.Costello, D.E.Groce, D.F.Herring, J.W.McGowan: Phys. Rev. B5, 1433 (1972)CrossRefADSGoogle Scholar
  12. 12.
    A.P.Mills, Jr., L.N.Pfeiffer: Phys. Rev. Lett.43, 1961 (1979);CrossRefADSGoogle Scholar
  13. 12a.
    A.P.Mills, Jr.: Appl. Phys. (to be published)Google Scholar
  14. 13.
    See A.P.Mills, Jr.: Solid State Commun.31, 623 (1979), and references thereinCrossRefGoogle Scholar
  15. 14.
    A.Steyerl: InNeutron Physics, Springer Tracts Mod. Phys.80 (Springer, Berlin, Heidelberg, New York 1977) pp. 57–130CrossRefGoogle Scholar

Copyright information

© Springer-Verlag 1980

Authors and Affiliations

  • A. P. MillsJr.
    • 1
  1. 1.Bell LaboratoriesMurray HillUSA

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