The universe never ceases to surprise us, and the latest revelation comes from the realm of nuclear physics. 

A vial of ultra-pure oxygen. (Hi-Res Images of Chemical Elements/CC BY 3.0)

Researchers led by Yosuke Kondo of the Tokyo Insтιтute of Technology have discovered two never-before-seen isotopes of oxygen—oxygen-27 and oxygen-28—that defy our current understanding of atomic nuclei. This groundbreaking discovery could reshape our knowledge of atomic structure and the so-called “magic numbers” that dictate the stability of atomic nuclei.

Oxygen-28, in particular, has caught the attention of scientists. With 20 neutrons, it has the highest number of neutrons ever observed in an oxygen atom. According to conventional wisdom, this should make it stable. 

However, the isotope decays rapidly, challenging our understanding of “magic numbers” in nuclear physics. 

These magic numbers are the number of nucleons (protons and neutrons) that make an atomic nucleus especially stable. Oxygen-28 was expected to be doubly magic, meaning both its proton and neutron shells should contain magic numbers, making it exceptionally stable. However, this is not the case.

A diagram of the experiment. (Nature)

The team made this discovery at the RIKEN Radioactive Isotope Beam Factory by firing a beam of calcium-48 isotopes at a beryllium target. This produced lighter atoms, including fluorine-29, which was then used to create oxygen-28. 

The results were surprising: both oxygen-27 and oxygen-28 are unstable, decaying into other forms in a short period. This has led scientists to question whether 20 is indeed a magic number for neutrons.

This discovery has far-reaching implications. It not only challenges our understanding of atomic nuclei but also opens up new avenues for research into the stability of other elements and isotopes. 

As we continue to delve into the intricacies of atomic structure, discoveries like this remind us that our understanding of the universe is still evolving. It’s a humbling reminder that in the grand scheme of things, we are still students of the cosmos, ever eager to unravel its mysteries.

Research Paper