What is the current estimate for the number of nuclides? This is a very basic question, but I'm finding it remarkably hard to get a reliable, up-to-date answer. A few books published in the last 2-3 years say it's greater than 3000, but this number seems to be changing rapidly: a Canadian Nuclear Association website says greater than 3100. There should be an easier way to find the answer than counting all the pixels in the Live Chart of Nuclides. I hoped that the Nuclear Wallet Cards search might be useful, but it isn't for this sort of question. I have a similar problem finding the current estimate for the number of stable nuclides.

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    $\begingroup$ There are going to be shades of gray between a nuclide that has definitely been observed and one that definitely has not. As a hypothetical example, someone could get one count in a gamma detector in coincidence with a nucleus recoiling through a mass spectrometer and having the right charge-to-mass ratio to be 98Sn. The gamma's energy matches shell model calculations for a 2+->0+ transition in 98Sn. Based on this, they publish a paper mentioning that they may have identified 98Sn. But the gamma could be compton scattering rather than the full energy peak, the coincidence could be random... $\endgroup$ – Ben Crowell Feb 16 at 3:09

A paper published in Nature (2012) states that there are just over 3000 nuclides but up to 7000 are possible. Even within those 7,000, the vast majority would be unstable, lasting only a tiny fraction of a second. Of the 3,000 known nuclides, only 288 are stable.

http://ne.phys.kyushu-u.ac.jp - states there are 2975 nuclides.
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  • $\begingroup$ Is there a version of that paper in English? $\endgroup$ – A. Newell Feb 16 at 17:21
  • $\begingroup$ Although your answer contains some useful information, it also illustrates the problem I'm facing. You have two estimates for the number of known nuclides (just over 3000 and 2975), while your figure of 288 for the number of stable nuclides is unsourced and can be added to the values of 253, 254, and 280 that I have seen in the literature. $\endgroup$ – A. Newell Feb 16 at 17:25
  • $\begingroup$ The quantity of 288 nuclides is given by Witold Nazarewicz of the University of Tennessee, the Oak Ridge National Laboratory in Tennessee and Warsaw University in Poland. $\endgroup$ – Rick Feb 16 at 20:42

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