Peering into the Creator's DESIGN: His Interwoven Balance of the Laws of Physics and Chemistry....
"This rare and unstable isotope doesn’t just decay, it unravels through a dramatic sequence of proton emissions that challenge long-held assumptions about nuclear structure. The finding marks the first known case of a “triple-proton decay chain,” and it may even hint at a break in the fundamental symmetry of atomic particles, opening a new frontier at the edge of nuclear stability.
What makes aluminum-20 special is not just that it exists briefly before vanishing; it’s how it vanishes. The decay pathway it follows is one of the rarest ever seen. First, it emits a single proton, turning
This process is known as three-proton emission, and aluminum-20 is the first nucleus ever discovered in which its direct decay product (magnesium-19) is itself a two-proton emitter. This extraordinary sequence provides nuclear physicists with a kind of Rosetta Stone—an intricate decay puzzle that reveals hidden information about nuclear forces, quantum behavior, and the boundaries of stability.
Currently, more than 3,300 nuclides are known, yet fewer than 300 are stable and exist naturally. The remainder are unstable nuclides that undergo radioactive decay.
Common decay modes, such as α decay, β- decay, β+ decay, electron capture, γ radiation, and fission, were discovered by the mid-20th century.
In the 21st century, two-proton radioactivity was found in the decays of some extremely neutron-deficient nuclei.
In recent years, even rarer decay phenomena such as three-, four-, and five-proton emission were observed.
“Aluminum-20 is the lightest aluminum isotope that has been discovered so far,” said Dr. Xiaodong Xu, a physicist with the Institute of Modern Physics at the Chinese Academy of Sciences.
“Located beyond the proton drip line, it has seven fewer neutrons than the stable aluminum isotope.”
Using an in-flight decay technique at the Fragment Separator of the GSI Helmholtz Center for Heavy Ion Research, the physicists.webp)
measured angular correlations of aluminum-20’s decay products.
Through detailed analysis of angular correlations, they found that the aluminum-20 ground state first decays by emitting one proton to the intermediate ground state of magnesium-19, followed by subsequent decay of magnesium-19 ground state via simultaneous two-proton emission.
Aluminum-20 is the first observed three-proton emitter where its one-proton decay daughter nucleus is a two-proton radioactive nucleus.
The researchers also found that the decay energy of the aluminum-20 ground state is significantly smaller than the predictions inferred from the isospin symmetry, indicating a possible isospin symmetry breaking in aluminum-20 and its mirror partner neon-20.
This finding is supported by state-of-the-art theoretical calculations that predict that the spin-parity of the aluminum-20 ground state differs from the spin-parity of the neon-20 ground state.
“This study advances our understanding of the proton-emission phenomena, and provides insights into the structure and decay of nuclei beyond the proton drip line,” Dr. Xu said."
Common decay modes, such as α decay, β- decay, β+ decay, electron capture, γ radiation, and fission, were discovered by the mid-20th century.
In the 21st century, two-proton radioactivity was found in the decays of some extremely neutron-deficient nuclei.
In recent years, even rarer decay phenomena such as three-, four-, and five-proton emission were observed.
“Aluminum-20 is the lightest aluminum isotope that has been discovered so far,” said Dr. Xiaodong Xu, a physicist with the Institute of Modern Physics at the Chinese Academy of Sciences.
“Located beyond the proton drip line, it has seven fewer neutrons than the stable aluminum isotope.”
Using an in-flight decay technique at the Fragment Separator of the GSI Helmholtz Center for Heavy Ion Research, the physicists
.webp)
Through detailed analysis of angular correlations, they found that the aluminum-20 ground state first decays by emitting one proton to the intermediate ground state of magnesium-19, followed by subsequent decay of magnesium-19 ground state via simultaneous two-proton emission.
Aluminum-20 is the first observed three-proton emitter where its one-proton decay daughter nucleus is a two-proton radioactive nucleus.
The researchers also found that the decay energy of the aluminum-20 ground state is significantly smaller than the predictions inferred from the isospin symmetry, indicating a possible isospin symmetry breaking in aluminum-20 and its mirror partner neon-20.
This finding is supported by state-of-the-art theoretical calculations that predict that the spin-parity of the aluminum-20 ground state differs from the spin-parity of the neon-20 ground state.
“This study advances our understanding of the proton-emission phenomena, and provides insights into the structure and decay of nuclei beyond the proton drip line,” Dr. Xu said."
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