  The hard X-ray flux ratio R of the footpoint sources to the loop-top source
has been used to investigate non-thermal electron trapping and precipitation in
solar flares. Considering the mission-long Yohkoh Hard X-ray Telescope
database, from which we selected 117 flares, we investigated a dependence of
the ratio R on flare loop parameters like height h and column depth N. We used
non-thermal electron beams as a diagnostic tool for magnetic convergence. The
ratio R decreases with h which we interpret as an effect of converging field
geometry. Two branches seen in the R-h diagram suggest that in the solar corona
two kinds of magnetic loops can exist: a more-converged ones that are more
frequent (above 80%) and less-converged loops that are less frequent (below
20%). A lack of correlation between the ratio R and N can be due to a more
complex configuration of investigated events than seen in soft X-rays. Obtained
values of the magnetic mirror ratio are consistent with previous works and
suggest a strongly nonpotential configuration. Further investigation including
RHESSI data is needed to verify our results.
