Oxygen-28 | Researchers discover a rare oxygen isotope defying expectations

In an extremely exciting advance for future nuclear experiments, physicists from the Tokyo Institute of Technology in Japan have discovered Oxygen-28 ( 28O) , a new isotope of Oxygen.  

During the experiment, the team fired a beam of calcium-48 isotopes at a beryllium target to produce lighter atoms, including fluorine-29, an isotope of fluorine with nine protons and 20 neutrons. Following this, the fluorine-29 was separated out and collided with a liquid hydrogen target to knock off a proton in an attempt to create oxygen-28.

A team of physicists led by nuclear physicist Yosuke Kondo of the Tokyo Institute of Technology in Japan has performed the experiment at a world leading nuclear physics beam factory in Japan.

Oxygen-28 (28O) specifications 

With an extremely large neutron to proton ratio, Oxygen-28 is exotic in nature and is the heaviest version of Oxygen ever created. According to the team of researchers in Japan, The Oxygen-28 nucleus is of particular interest in nuclear physics, as with the proton number Z = 8 and neutron number N = 20 being both 'magic numbers', it is expected to be one of a relatively small number of so-called 'doubly magic' nuclei in the standard shell-model picture of nuclear structure.

Why is the discovery of 28O a big deal? 

The study of rare isotopes with significant neutron/proton imbalances, like 28O, is one of the most active fields in nuclear physics today.

According to Durham University, “The most advanced ab initio theories used in nuclear physics are based on effective versions of quantum chromodynamics and are highly sophisticated, which take hundreds of hours on supercomputers to evaluate.”

Durham University further stated that the process makes them “too slow to produce realistic predictions, hence inhibiting the core scientific process of comparing theory to experiment.”

How did the experiment take place?

The team in their experiment utilized the ground-breaking UQ methods (emulation and history matching) developed in the Mathematical Sciences department to show that the measurement of 28O properties can provide valuable constraints of such theoretical approaches and, most importantly, the particular nuclear interactions employed.

Advanced UQ techniques facilitated the essential scientific procedure of comparing theoretical predictions with experimental results and allowed the study team to make accurate predictions of the properties of 28O, which were previously entirely intractable.