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Phys.org's 'Strange' glimpse into neutron stars and symmetry violation leads to the new Nature Physics Letter Measurement of the mass difference and the binding energy of the hypertriton and antihypertriton and that led me to Wikipeida's Hypertriton which says:

Normal nuclei are formed only of protons and neutrons. To study them, scientists arrange the various nuclides into a two-dimensional table of nuclides. On one axis is the number of neutrons N, and on the other is the number of protons Z. Because the antihyperon introduces a third component (strangeness), the table becomes three-dimensional.

However the article only shows the more familliar two-dimensional Z vs N Chart of Nuclides something like that shown below.

which leads me to ask:

Question: What would a 3D chart of nuclides actually look like (neutron and proton number and strangeness; $N$, $Z$, $S$)? Has one been made? If so, what information is entered for each entry?


Example of a more conventional 2D $Z$ vs $N$ chart:

enter image description here

click for larger, Source

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    $\begingroup$ Free hyperons have half-lives of less than a nanosecond. I guess they might be stabilized slightly when bound into nuclei. But I expect it'd be pretty hard to construct heavy hyperon nuclei. $\endgroup$ – PM 2Ring Mar 10 at 6:38
  • $\begingroup$ and certainly the height as a third dimension in the plot) would be one hyperon/ antihyperon nucleus high., incontrast to having variable nucleons in the standard table $\endgroup$ – anna v Mar 10 at 7:16
  • $\begingroup$ @PM2Ring the old Chart of the Nuclides suitable for framing included lifetimes well below 1E-17 seconds (widths really) for things like 5He 5Li and 8Be so that shouldn't be a problem. $\endgroup$ – uhoh Mar 10 at 8:09
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    $\begingroup$ Note that that chart is already three dimensional. Two axis are $Z$ and $N$, but the coloring relates to stability and is, in effect, a third dimension to the chart. $\endgroup$ – StephenG Mar 10 at 8:19
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    $\begingroup$ It is hard enough to do experiments with one, they are very short lived $\endgroup$ – anna v Mar 10 at 9:35
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(This anecdote kind of straddles the line between a comment and an answer.)

I saw the beginning of such a table in a conference presentation a decade ago. The format was the same as the usual (Z,N) chart of nuclides, but the data were measured lifetimes for hypernuclei where one baryon was a $\Lambda$. The heaviest nuclei on this chart had mass number $A\lesssim5$ --- it was just the low-mass corner of the table of isotopes.

I suppose you could construct such a table for nuclei where one baryon is a $\Sigma$ with some charge quantum number. Nuclei with more than one strange baryon are unlikely to be experimentally accessible. So the presentation wouldn't really by three-dimensional; it'd be a series of similar-looking two-dimensional diagrams. Nuclides with one $\Lambda$ hyperon, nuclides with one $\Sigma^+$ hyperon, etc.

I only vaguely remember this conference presentation, but I think the presenter was describing work done in Jefferson Lab's Hall B. That might be enough information to point a motivated sleuth towards an actual publication.

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    $\begingroup$ Do you know if any of those nuclides have longer lifetimes than the hyperons they contain? (i.e., whether the weak decay is stabilised by the surrounding nucleons?) If it isn't, the chart won't show much information beyond just cataloguing experimental observations that the nuclides can be generated. $\endgroup$ – Emilio Pisanty Mar 12 at 10:27
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    $\begingroup$ Apparently there are predictions that bound $\Lambda$ have a shorter lifetime than free $\Lambda$, because the weak process $\Lambda N \to NN$ becomes available as a new decay channel. This recent review also discusses predicting and measuring binding energies in a way that might be nice to systematize on an $(N,Z)$ chart --- as is done here for the non-strange nuclei. $\endgroup$ – rob Mar 12 at 11:39

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