A COMMENT ON THE ASYMPTOTIC HIGH-ENERGY BEHAVIOR OF 1ST BORN IONIZATION CROSS-SECTIONS Academic Article uri icon

abstract

  • The authors write down precisely what is determined by measuring the ratio, R, of the cross sections for double to single ionization, produced by a beam of bare projectiles, charge Zp, incident at high energy on a helium target. They confirm the general, nonrelativistic, behaviour of the reaction cross sections, sigma r, to be of the form predicted by Bethe (1930), i.e. as a function of the projectile energy, Ep, to behave as formula presente We arbiterarily set E0 to 1 keV amu-1. When we calculate σrab initio, For proions incident on helium we can extract Br and Cr Our value for Cr is different from that given by Sidorovich for double ionization. The analysis suggests that the asymptotic formula is accurate above 10 MeVamu-1 and that, as the energy is raised further, our calculated R increases slowly; it rises to 0.0027 at 200 MeV amu-1, some 5% above its value at 10 MeVamu-1. In comparison, we calculate that the Sidorovich value of Cr gives a change of 27% over this energy range. The experimental data are not Sumeiently accurate yet to differentiate between these two predictions. We also discuss the different asymptotic farms for single and double ionization as a function of the paritgof the transition. © 1991 IOP Publishing Ltd.

published proceedings

  • JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS

author list (cited authors)

  • HALL, K., READING, J. F., & FORD, A. L.

citation count

  • 2

complete list of authors

  • HALL, K||READING, JF||FORD, AL

publication date

  • December 1991