Zinc-54 undergoes rare 2 proton decay

[Astronuc]

From the Alchemist Newsletter (Chemweb.com)

An international team of researchers has produced a new isotope of zinc, zinc-54, which they say undergoes the rare process of two-proton decay. The research carried out by Bertram Blank of the CENBG laboratory in France and colleagues could shed light on what how protons stay together in the atomic nucleus. Carrying out nuclear physics experiments with this new isotope is relatively straightforward but don't expect to see it bottled for off-the-shelf chemistry. The manufacturing process is very low yield with only one in 10 to the 17 collisions between nickel-58 atoms and a nickel target yielding the novel zinc-54 species.

more at New isotope doubles

 

[ohwilleke]

Just to be clear, the protons themselves aren't decaying, rather the zinc is emitting two protons at once, rather than the usual alpha, beta or gamma decay modes.

 

[Rade]

I am a bit unclear about the information provided at the PhysicsWeb link -- they seem to imply that "double proton emission" is only known for Fe-45 and now Zn-54.

However, the following link from Jefferson Lab: http://education.jlab.org/itselemental/iso001.html clearly shows the experimentally documented "double proton emission" for Be-6, Si-23, S-27, Ca-35, Fe-45, Zn-54, Ge-58, and Ge-59. So this phenomenon is not as rare as presented. Also, the Jefferson Lab site lists "double neutron emmision" for He-10, B-15, B-17, C-22, K-53, Ru-100.

Together, these data seem to imply that there exists within some isotopes a [PP] or [NN] halo type nucleon cluster with realistic 6-quark quasi-bound structure (uud)+(uud) and (ddu)+(ddu) ? I find it highly unlikely that two "free" protons or neutrons just happen to be emitted at the exact same time in all of these "double emission" events--but perhaps I am incorrect and someone can help me understand the required physics to allow this to happen.