Beta Decay, why did they have to resort to Neutrinos?

[Vanadium 50]

It matched good enough in the 1930's at least to call Fermi's theory a "success".

Fermi's theory did not predict a phase-space like spectrum (see above), Indeed, one of the successes of the theory was that it got the spectrum right.

 

[vanhees71]

But not 3-body phase space. You need the $q^5/M_W^4$ to match data,

Sure, but that was explained theoretically only later by Fermi's weak-interaction model, using Pauli's hypothesis about the particle we call neutrino today (in 1930 Pauli called it neutron, but then they named the neutron neutron, which was discovered in 1932; so finally the name neutrino was given to Pauli's hypothetical particle).

 

[jtbell]

@mfb @hutchphd @Vanadium 50 @vela
Thanks for your comments. I take it that you, like me, haven't found a list of papers from 1911~1929AD on hypotheses for beta decay energy sources.

I apologize for this delayed response. I came across this thread only just now, in the list of "suggested threads" at the end of a more recent discussion about beta decay.

While working on my PhD in experimental neutrino physics many years ago, I collected some photocopies of historical articles about the neutrino. The first item in that binder is a very nice historical summary with about 20 references to papers from the 1920s and 1930s:

Laurie M. Brown, "The idea of the neutrino", Physics Today, September 1978.

There's also this:

W. Pauli, "Zur älteren und neueren Geschichte des Neutrinos", based on a lecture he gave in 1957 and subsequently published in Aufsätze und Vorträge über Physik und Erkenntnisthorie (V. F. Weisskopf, ed., 1961). I found it in his Collected Scientific Papers (1964), vol. 2. This is also very readable (if you can read German, that is) and provides some more references to early papers.