I have received the following as a comment to the website. I strongly believe this is an important advocate of our website and motivation behind organizing it, as well as a good read for all people in the field of nuclear physics. Here it is:
Dear Theo,
I have previously relied on Nick Stone’s compilation, but I am happy to have found your website with active updating of nuclear magnetic moments. This is why the internet is so wonderful, so I wish you luck in drawing attention to this valuable resource!
Maybe anyone interested in magnetic moments already understands this, but what I think is still missing from your website is indication of the importance of specifically the magnetic moments for a proper understanding of nuclear structure.
On the one hand, the textbooks typically show the Schmidt Lines, together with data points indicating that most experimental values lie between the upper and lower values. Already by the early 1950s, the Schmidt lines clearly indicated that the independent-particle model was more-or-less valid, but there has been surprisingly little progress since then. Because the modern experimental data are precise up to 7 or 8 digits and classical electromagnetic theory is well understood, explanation of nuclear magnetic moments SHOULD be (but is not yet) an area where discrepancies between experiment and theory might be discussed with some clarity!
On the other hand, theorists who calculate nuclear magnetic moments typically use model parameters that are adjusted to reproduce the experimental data. Adjusting the parameters of the nuclear models is entirely normal practice, but such modeling gives the impression that the magnetic moments are understood quantitatively, whereas the truth is considerably less optimistic. That “hard reality” is not often acknowledged, I would say, but last year a Chinese physics journal, SCIENCE CHINA, was rather straight-forward in stating the continuing problems in explaining nuclear magnetic moments.
http://esciencenews.com/articles/2010/12/23/nuclear.magnetic.moments
In explaining why they were to publish a Special Issue devoted to nuclear moments, the Editors noted that:
“the extension of these [nuclear] models to the study of nuclear magnetic moments is quite limited and unsatisfactory. The magnetic dipole moments of most atomic nuclei throughout the periodic table still remain unexplained and the under-lying physics mechanism is not fully understood….”
And, among the invited reviews of theoretical work that were eventually published, Akito Arima went through the usual explanation of the Schmidt lines, and even cited the good agreement between experiment and theory for a few selected nuclei from his own work published in…. 1954!
I would guess that you are not interested in getting into abstruse theoretical discussions on your web-site, but I think some indication of the current lack of theoretical understanding of nuclear magnetic moments would indicate why nuclear moments are indeed an important topic!
Cheers
Norman
N.D.Cook
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