Advertisement

Dipole enhancement of the protonium formation cross section in antiproton collisions with excited hydrogen atoms

  • Kazuhiro SakimotoEmail author
Regular Article
Part of the following topical collections:
  1. Topical Issue: Low Energy Positron and Electron Interactions

Abstract

Between an ion and a hydrogen (H) atom in an excited state, there exists an effectively isotropic interaction potential which behaves as 1/R2 at large separations R. The abnormal long-range part, stemming from the energy degeneracy peculiar to the H system, is expected to have a drastic influence on the low-energy collision processes. The present paper addresses this issue by considering protonium (p) formation in antiproton () collisions with excited H atoms. The calculation of the p formation process is carried out by means of a semiclassical (quantum-classical hybrid) approach. At low collision energies E, the formation cross section is found to be far above the so-called Langevin cross section and reveals the E-1 dependence. This result is in clear contrast to that for the H atoms in the ground state with no degeneracy.

Graphical abstract

References

  1. 1.
    P. Langevin, Ann. Chem. Phys. 5, 245 (1905) Google Scholar
  2. 2.
    G. Gioumousis, D.P. Stevenson, J. Chem. Phys. 29, 294 (1958) ADSCrossRefGoogle Scholar
  3. 3.
    W. Lenz, Z. Phys. 24, 197 (1924) ADSCrossRefGoogle Scholar
  4. 4.
    W. Pauli, Z. Phys. 36, 336 (1926) ADSCrossRefGoogle Scholar
  5. 5.
    J.W.B. Hughes, Proc. Phys. Soc. 91, 810 (1967) ADSCrossRefGoogle Scholar
  6. 6.
    Yu.N. Demkov, B.S. Monozon, V.N. Ostrovskiĭ, Sov. Phys. JETP 30, 775 (1970) ADSGoogle Scholar
  7. 7.
    T.F. Moran, W.H. Hamill, J. Chem. Phys. 39, 1413 (1963) ADSCrossRefGoogle Scholar
  8. 8.
    J.V. Dugan Jr., J.L. Magee, J. Chem. Phys. 47, 3103 (1967) ADSCrossRefGoogle Scholar
  9. 9.
    K. Sakimoto, Chem. Phys. 63, 419 (1981) ADSCrossRefGoogle Scholar
  10. 10.
    K. Sakimoto, Chem. Phys. Lett. 116, 86 (1985) ADSCrossRefGoogle Scholar
  11. 11.
    A.S. Kadyrov, C.M. Rawlins, A.T. Stelbovics, I. Bray, M. Charlton, Phys. Rev. Lett. 114, 183201 (2015) ADSCrossRefGoogle Scholar
  12. 12.
    C.M. Rawlins, A.S. Kadyrov, A.T. Stelbovics, I. Bray, M. Charlton, Phys. Rev. A 93, 012709 (2016) ADSCrossRefGoogle Scholar
  13. 13.
    B.M. Gailitis, R. Damburg, Proc. Phys. Soc. 82, 192 (1963) ADSCrossRefGoogle Scholar
  14. 14.
    T.F. O’Malley, Phys. Rev. 137, A1668 (1965) CrossRefGoogle Scholar
  15. 15.
    I. Shimamura, Phys. Rev. A 40, 4863 (1989) ADSCrossRefGoogle Scholar
  16. 16.
    I.I. Fabrikant, A.W. Bray, A.S. Kadyrov, I. Bray, Phys. Rev. A 94, 012701 (2016) ADSCrossRefGoogle Scholar
  17. 17.
    G.B. Andresen et al., Phys. Rev. Lett. 105, 013003 (2010) ADSCrossRefGoogle Scholar
  18. 18.
    G. Gabrielse et al., Phys. Rev. Lett. 106, 073002 (2011) ADSCrossRefGoogle Scholar
  19. 19.
    B.I. Deutch et al., Hyperfine Interact. 76, 153 (1993) ADSCrossRefGoogle Scholar
  20. 20.
    C.H. Storry et al., Phys. Rev. Lett. 93, 263401 (2004) ADSCrossRefGoogle Scholar
  21. 21.
    D. Krasnický et al., Int. J. Mod. Phys. Conf. Ser. 30, 1460262 (2014) CrossRefGoogle Scholar
  22. 22.
    D.P. van der Werf, Int. J. Mod. Phys. Conf. Ser. 30, 1460263 (2014) CrossRefGoogle Scholar
  23. 23.
    P. Peŕez et al., Hyperfine Interact. 233, 21 (2015) ADSCrossRefGoogle Scholar
  24. 24.
    Y. Yamazaki, Nucl. Instrum. Methods Phys. Res. B 154, 174 (1999) ADSCrossRefGoogle Scholar
  25. 25.
    N. Kuroda et al., Phys. Rev. Spec. Top. Accel. Beams 15, 024702 (2012) ADSCrossRefGoogle Scholar
  26. 26.
    J.S. Cohen, Rep. Prog. Phys. 67, 1769 (2004) ADSCrossRefGoogle Scholar
  27. 27.
    A.Yu. Voronin, J. Carbonell, Phys. Rev. A 57, 4335 (1998) ADSCrossRefGoogle Scholar
  28. 28.
    K. Sakimoto, Phys. Rev. A 65, 012706 (2001) ADSCrossRefGoogle Scholar
  29. 29.
    K. Sakimoto, Phys. Rev. A 66, 032506 (2002) ADSCrossRefGoogle Scholar
  30. 30.
    N. Yamanaka, A. Ichimura, Phys. Rev. A 74, 012503 (2006) ADSCrossRefGoogle Scholar
  31. 31.
    X.M. Tong, K. Hino, N. Toshima, Phys. Rev. Lett. 97, 243202 (2006) ADSCrossRefGoogle Scholar
  32. 32.
    X.M. Tong, T. Shirahama, K. Hino, N. Toshima, Phys. Rev. A 75, 052711 (2007) ADSCrossRefGoogle Scholar
  33. 33.
    K. Sakimoto, Phys. Rev. A 88, 012507 (2013) ADSCrossRefGoogle Scholar
  34. 34.
    S.Yu. Ovchinnikov, J.H. Macek, Phys. Rev. A 71, 052717 (2005) ADSCrossRefGoogle Scholar
  35. 35.
    J.S. Briggs, P.T. Greenland, E.A. Solov’ev, J. Phys. B 32, 197 (1999) ADSCrossRefGoogle Scholar
  36. 36.
    K. Sakimoto, Phys. Rev. A 91, 042502 (2015) ADSCrossRefGoogle Scholar
  37. 37.
    K. Sakimoto, Phys. Rev. A 84, 032501 (2011) ADSCrossRefGoogle Scholar
  38. 38.
    R.F. Wallis, R. Herman, H.W. Milnes, J. Mol. Spectrosc. 4, 51 (1960) ADSCrossRefGoogle Scholar
  39. 39.
    E. Fermi, E. Teller, Phys. Rev. 72, 399 (1947) ADSCrossRefGoogle Scholar
  40. 40.
    A.S. Wightman, Phys. Rev. 77, 521 (1949) ADSCrossRefGoogle Scholar
  41. 41.
    J.E. Turner, Am. J. Phys. 45, 758 (1977) ADSCrossRefGoogle Scholar
  42. 42.
    C.A. Coulson, M. Walmsley, Proc. Phys. Soc. 91, 31 (1967) ADSCrossRefGoogle Scholar
  43. 43.
    O.H. Crawford, Proc. Phys. Soc. 91, 279 (1967) ADSCrossRefGoogle Scholar
  44. 44.
    M. Kotani, K. Ohno, K. Kayama, Quantum mechanics of electronic structure of simple molecules, Handbuch der Physik XXXVII/2 (Springer-Verlag, Berlin, Göttingen, Heidelberg, 1961) Google Scholar
  45. 45.
    L.D. Landau, E.M. Lifshitz, in Quantum mechanics, 3rd edn. (Pergamon, Oxford, 1977) Google Scholar
  46. 46.
    B.L. Jhanwar, W.J. Meath, Mol. Phys. 40, 713 (1980) ADSCrossRefGoogle Scholar
  47. 47.
    K. Sakimoto, Chem. Phys. 249, 1 (1999) ADSCrossRefGoogle Scholar
  48. 48.
    G.M. Stacey, Proc. Phys. Soc. Lond. 88, 897 (1966) ADSCrossRefGoogle Scholar
  49. 49.
    D. Krasnický, R. Caravita, C. Canali, G. Testera, Phys. Rev. A 94, 022714 (2016) ADSCrossRefGoogle Scholar
  50. 50.
    J.C. Day, T. Ehrenreich, S.B. Hansen, E. Horsdal-Pederesen, K.S. Mogensen, K. Taulbjerg, Phys. Rev. Lett. 72, 1612 (1994) ADSCrossRefGoogle Scholar
  51. 51.
    K.S Mogensen, J.C. Day, T. Ehrenreich, E. Horsdal-Pederesen, K. Taulbjerg, Phys. Rev. A 51, 4038 (1995) ADSCrossRefGoogle Scholar
  52. 52.
    K.B. MacAdam, E. Horsdal-Pederesen, J. Phys. B 36, R167 (2003) ADSCrossRefGoogle Scholar

Copyright information

© EDP Sciences, SIF, Springer-Verlag GmbH Germany, part of Springer Nature 2018

Authors and Affiliations

  1. 1.Institute of Space and Astronautical Science, Japan Aerospace Exploration AgencySagamiharaJapan

Personalised recommendations