  This much revised and shortened PhD thesis contains many ideas that I could
not follow up on, like self destructing beams in scattering cells, the
depletion enhancing Wittig tube, ionic seeding via beta-decay foil or
Langmuir-Taylor filaments, analysis of the popular <N> ~ Delta(N) relation in
droplet size distributions, etc. Avoiding pasting again the usual that is found
in many a thesis in the He-droplet field, we focus instead on what is presented
insufficiently rigorous elsewhere, like chopper selection, ionization yield
curves, or certain widely employed yet wrong derivations. It is not telling
much about successes (e.g. first observation of alkali clusters A_k on He_N
with k > 3, proof of their surface location, prediction of constant signal
ratios via spin statistics) but goes mainly into the failures, as these are
more interesting to those who like to explore truly new territory. Some ideas
here may just need a single good insight of yours to turn them into success.
