I How is the fission of Uranium to Europium possible?

[barnflakes]

According to the following website listing the yields of fission products for Uranium and other transuranic isotopes:

https://www-nds.iaea.org/sgnucdat/c3.htm

The fission product 63-Eu-155 is rare but not impossible.

According to my maths, this means there must be another daughter nuclei with atomic number 29 in order to conserve charge etc.

However, Copper (with atomic number 29) is not in the list of fission products, nor any element with an atomic number lower than this.

Therefore, I wonder how the fission of Uranium to Europium is possible?

The only way I can see this becoming possible is for Uranium to split into Europium and to release several alpha particles or protons in the process, but I have not heard of this happening.

Can anyone shed any light on this?

 

[scottdave]

What about Hydrogen and Helium nuclei? You did say it is rare. Perhaps that's why you don't hear about it.

 

[mfb]

Summing over the fast fission products for 92-U-233, I get 114.5%. For U-235, I get 118.7%. As every fission produces at least two nuclei, I would expect the total sum to add up to roughly 200%. The list doesn't look complete. Another way to see that: It misses many ternary fission products.

Edit: A few isotopes have the same yields, e.g. 42-Mo-99 and 43-Tc-99 or 44-Ru-106 and 45-Rh-106. They are connected via beta decays (including some very long-living nuclides). If I remove these the sum of yields reduces to ~105%.