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lYoblems of interpreting the imclaar abundance distribution
Theories of the origin of the eletitents
The nuclear abundance distribution as derivfxi from the discussion above,
supplies a basis for comparison of empirical data with the various theories of
the origin of the nuclear specieSo
No such comparison will be given here,
and the reader is referred to thrcaexcellent review articles by Alpher and
^Herman (1950/1953) on the theory of the origin and relative abtmdance
distribution of the elements dealing with this subject, in which sone IBO
papers are critically discussed-
It is shown there that none of the existing
theories can account for all of the empirical facts, even in a crude way©
Hence, It seems hopeless to attempt to explain the finer details presented
here by any of these theories in their present form.
It seems possible, however, that a modification of one theory or the other,
in pairticular through assun^xtions regarding secondary and subsequent reactions,
may load to a satisfactory agreement.
We hope that tl» following discussion will
be helpful for the study of the nature of such reactions»
ISie nuclear abundance values obtained in the way described above differ
in son© mass regions quite noticeably frcwi orevlous estimates (Suess 19U9).
A comparison, howe^^r, of figure I with the corresponding figure published
previously shows that the main features of the abundance distribution have
been retaii»do
TI»se features are essentially independent of the choice of the
element abundance and constitute well-defined probleraSi, which will be discussed
in the followingo
This discussion will not be a complets one, and it will be left
to the reader to detect many more features in figure 1 "srtiich might ssrve
as evidence
for or against the prevailing of a certain mechanism of element forraationo
An impressive difference exists between the character of the region of the
lighter (A 90) nucleio
In the lower A region the line