account of the dependence of coefficient α on the ini
tial charge of the ions as
(6)
where α0 and k1 are approximately equal to the above
values, and k2 varies from 0.02 at V = 4 × 108
cm/s to
0.12 at V = 12 × 108
cm/s. The results obtained using
expressions (4) and (6) (solid lines) are consistent with
the experimental data and more complex calculations
based on the numerical solution to system (1) (dashed
lines).
CONCLUSIONS
Our analysis of the dependence of the average
charges of light ions on the thickness of a celluloid tar
get and on the initial charge of the ions has shown on
the basis of experimental data the possibility of using
expression (3) in a twocomponent approximation to
describe the process of establishing the charge equilib
rium for He ions, as well as for more complex ions
(e.g., for N ions). Coefficient α included in (3) was
calculated on the basis of the experimental data for the
particular ions under consideration at a particular
energy. The values found for α can be successfully used
to calculate the equilibrium thickness values of a cel
luloid target.
The proposed semiempirical method is useful for
analyzing the processes that occur during the passage
of ions through a thin celluloid target with a thickness
of less than teq. Using approximation (3) to determine
greatly simplifies calculations of various physical
characteristics, e.g., the ion energy loss. It is necessary
to validate the applicability of the proposed method
for describing the formation of average charges over a
wide range of ions in various targets in order to deter
mine the values of selected coefficients on the basis of
the experimental data. With a sufficient experimental
data array, expressions (3) for and (4) for teq, in
dependence on the target’s thickness and the initial
charge of the ions, can be used to study the passage of
beams of light ions of various composition through
targets of varying thickness and more complex compo
sition.