µ+ Charge Exchange, Muonium Formation and Depolarizaton in Gases

  • Donald G. Fleming
  • Masayoshi Senba
Part of the NATO ASI Series book series (NSSB, volume 169)


The muon, like the electron, can be found in two charge states, µ+ and µ, and can be produced at ‘MeV’ energies and 100% (longitudinally) polarized from π → µv decay.1 Most of this initial energy is lost in ionization processes as the muon slows down, during which no loss in polarization occurs. At ‘keV’ energies, when the muon velocity is comparable to orbital electron velocities in the moderator, additional mechanisms begin to dominate the energy loss process. Negative muons are captured into highly excited “mesic” orbits and because of this are often referred to as “heavy electrons” (mµ = 206 me). They are not considered further here. Positive muons suffer an entirely different fate. At ‘keV’ energies, the µ+ undergoes charge exchange with the moderator, producing the muonium atom (Mu = µ+e) and returning the free muon in a series of charge exchange cycles, which can be thought of in complete analogy with those for protons. Subsequent thermalization at ‘eV’ energies is accomplished by elastic and inelastic scattering processes. The same features underlie the Ore concept of positronium (Ps) formation in gases1, but the µ+ in matter acts much more like a light proton (mµ = 1/9 mp) than a heavy positron, a theme which is emphasized throughout this paper.


Charge Exchange Neutral Fraction Electron Loss Muonium Atom Positronium Formation 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. 1.
    H.S.W. Massey, E.H.S. Burhop and H.B. Gilbody, “Electronic and Ionic Impact Phenomena”, Vol. 5, “Slow Positron and Muon Collisions”, Oxford-Claredon Press, 1974.Google Scholar
  2. 2.
    B.H. Bransden, Rep. Prog. Phys. 35, 949 (1972)ADSCrossRefGoogle Scholar
  3. H. Tawara and A. Russek, Rev. Mod. Phys. 45, 178 (1973).ADSCrossRefGoogle Scholar
  4. 3.
    E. Rille, R.E. Olson, J.L. Peacher, D.M. Blankenship, T.J. Krale, E. Redd and J.T. Park, Phys. Rev. Letts. 49, 1819 (1982).ADSCrossRefGoogle Scholar
  5. 4.
    S.K. Allison, Rev. Mod. Phys. 30, 1137 (1958).ADSCrossRefGoogle Scholar
  6. 5.
    S.L. Varghese, G. Bissinger, J.M. Joyce and R. Loubert, Phys. Rev. 31A, 2202 (1985).ADSGoogle Scholar
  7. 6.
    J.H. Newman, J.D. Cogan, D.L. Ziegler, D.E. Nitz, R.D. Rundel, K.A. Smith and R.F. Stebbings, Phys. Rev. 25A, 2976 (1982).ADSGoogle Scholar
  8. 7.
    D.G. Fleming, R.J. Mikula and D.M. Garner, Phys. Rev. 26A, 2527 (1982).ADSGoogle Scholar
  9. 8.
    M. Senba, J. Phys. B, to be submitted; M. Senba et al., contributed paper, XV ICPEAC, Brighton, July, 1987.Google Scholar
  10. 9.
    E. Roduner, Prog. Reaction Kinetics 14, 1 (1986).Google Scholar
  11. 10.
    R.H. Heffner and D.G. Fleming, Phys. Today, Dec. 1984, p. 2.Google Scholar
  12. 11.
    D.J. Arseneau, D.M. Garner, M. Senba and D.G. Fleming, J. Phys. Chem. 88, 3688 (1984)CrossRefGoogle Scholar
  13. D.J. Arseneau, M.Sc. Thesis, Univ. of British Columbia, 1984.Google Scholar
  14. 12.
    D.G. Fleming, Radiat. Phys. Chem. 28, No. 1, 115 (1986).Google Scholar
  15. 13.
    D.M. Garner, D.G. Fleming and R.J. Mikula, Chem. Phys. Letts. 121, 80 (1985)ADSCrossRefGoogle Scholar
  16. I.D. Reid et al., J. Chem. Phys., in press (1987).Google Scholar
  17. 14.
    M. Senba, D.M. Garner, D.J. Arseneau and D.G. Fleming, Hyp. Int. 17–19 703 (1984)Google Scholar
  18. D.G. Fleming, R.J. Mikula and D.M. Garner, J. Chem. Phys. 73, 2751 (1980).ADSCrossRefGoogle Scholar
  19. 15.
    R.E. Turner and M. Senba, J. Chem. Phys. 84, 3776 (1986)ADSCrossRefGoogle Scholar
  20. R.E. Turner and M. Senba, Phys. Rev. 29A, 2541 (1984).ADSGoogle Scholar
  21. 16.
    D.G. Fleming, M. Senba, D.J. Arseneau, I.D. Reid and D.M. Garner, Can. J. Chem. 64, 57 (1986).CrossRefGoogle Scholar
  22. 17.
    M. Senba, R.E. Turner, D.J. Arseneau, D.M. Garner, L.Y. Lee, I.D. Reid and D.G. Fleming, Hyp. Int. 32, 795 (1986).ADSCrossRefGoogle Scholar
  23. 18.
    M.E. Rudd, R.D. Dubois, L.H. Toburen, C.A. Ratcliffe and T.V. Goffe, Phys. Rev. 28A, 3244 (1983);ADSGoogle Scholar
  24. G. Lapicki and F.D. McDaniel, Phys. Rev. 22A, 1896 (1980).ADSGoogle Scholar
  25. 19.
    D.J. Malcolm-Lawes, in “Hot Atom Chemistry: recent trends and applications”, T. Matsuura, ed., Kodansha Ltd., Tokyo, 1984, p. 39.Google Scholar
  26. 20.
    D.M. Schraeder and R.E. Svetic, Can. J. Phys. 60, 517 (1982).ADSCrossRefGoogle Scholar
  27. 21.
    J.B.H. Stedeford and F.B. Hasted, Proc. Roy. Soc., A227, 466 (1955).ADSGoogle Scholar
  28. 22.
    H. Tawara, At. Data Nucl. Data Tables 22, 491 (1978).ADSCrossRefGoogle Scholar
  29. 23.
    F. Roussel, P. Pradel and G. Spiess, Phys. Rev. A16, 1854 (1977).ADSGoogle Scholar
  30. 24.
    E.S. Solov’ev, R.N. Il’in, V.A. Oparin and N.V. Fedorenko, Soviet Phys. JETP (Eng. Trans.) 15, 459 (1962).Google Scholar
  31. 25.
    D.N. Ruzic and S.A. Cohen, J. Chem. Phys. 83, 5527 (1985).ADSCrossRefGoogle Scholar
  32. 26.
    G. Bischof, V. Hermann, J. Krutein and F. Linder, J. Phys. B At. Mol. Phys. 15, 249 (1982)ADSCrossRefGoogle Scholar
  33. D.W. Davies and S.J. Till, Mol. Phys. 39, 757 (1980)ADSCrossRefGoogle Scholar
  34. G.D. Billing, Chem. Phys. 30, 387 (1978).MathSciNetADSCrossRefGoogle Scholar
  35. 27.
    S. Aronowitz, T. Scattergood, J. Flores and S. Chang, J. Phys. Chem. 90, 1806 (1986).CrossRefGoogle Scholar
  36. 28.
    G. Bissinger, J.M. Joyce, G. Lapicki, R. Loubert and S.L. Varghese, Phys. Rev. Letts. 49, 318 (1982).ADSCrossRefGoogle Scholar
  37. 29.
    D.G. Fleming, R.J. Mikula, M. Senba, D.M. Garner and D.J. Arseneau, Chem. Phys. 82, 75 (1983)CrossRefGoogle Scholar
  38. D.J. Arseneau, Ph.D. Thesis, in progress.Google Scholar
  39. 30.
    G.R. Heyland, M. Charlton, T.C. Griffith and G. Clark, Chem. Phys. 95, 157 (1985)CrossRefGoogle Scholar
  40. G.L. Wright, M. Charlton, G. Clark, T.C. Griffith and G.R. Heyland, J. Phys. B16, 4065 (1983).ADSGoogle Scholar
  41. 31.
    F.M. Jacobsen, “Proc. of NATO Workshop on e+ Scattering in Gases”, Plenum Press, New York, 1983, p. 85Google Scholar
  42. F.M. Jacobsen, Chem. Phys. 101, 259 (1986).ADSCrossRefGoogle Scholar
  43. 32.
    F.M. Jacobsen, Hyp. Int. 31, 501 (1986).ADSCrossRefGoogle Scholar
  44. 33.
    O.E. Mogensen and P.W. Percival, Rad. Phys. Chem. 28 No. 1, 85 (1986)Google Scholar
  45. P.W. Percival, J.C. Brodovitch and K.E. Newman, Hyp. Int. 17–19 721 (1984).Google Scholar

Copyright information

© Plenum Press, New York 1987

Authors and Affiliations

  • Donald G. Fleming
    • 1
  • Masayoshi Senba
    • 1
  1. 1.TRIUMF and Department of ChemistryUniversity of British ColumbiaVancouverCanada

Personalised recommendations