Creating a strange, pumpkin-shaped atomic nucleus

The lutetium-149 nucleus has the shortest half-life of any group of radioactive elements known as proton emitters, according to PhysicsWorld. It loses half its radioactivity (decays into other elements) in just 450 nanoseconds.

Pumpkin-shaped weird kernels

Lutetium is a rare earth element that occurs naturally as a silvery metal with 71 protons and 71 neutrons in its nucleus. It usually occurs with the metallic element ytterbium in the Earth's crust.

In the 1980s, scientists observed that an isotope of lutetium - a variant of the atom with a different number of neutrons in the nucleus - called lutetium-151, decayed and ejected a proton from the nucleus. its ground state. Proton emission is rare, and lutetium-151 is the first isotope observed to emit a proton while decaying in its steady ground state.

Studying proton decay allows researchers to look inside the nucleus of an atom and understand how protons and neutrons bind together. As part of this line of research, Kalle Auranen, a postdoctoral researcher in physics at the University of Jyväskylä, and colleagues created a new isotope of lutetium, lutetium-149, which has 71 protons and 78 neutrons in its nucleus.

They found that lutetium-149 is even more exotic than lutetium-151. However, its nucleus is not a neat sphere, but an elongated sphere that looks a bit like a pumpkin. This is called mass distortion, and lutetium-149 is the most distorted nucleus ever measured.

The blink half-life of Lutetium-149 is also significantly shorter than the half-life of 80.6 milliseconds of lutetium-151.

The researchers created the isotope by firing an isotope of nickel, nickel-58, at an isotope of ruthenium, ruthenium-96, according to PhysicsWorld. The new lutetium isotope decays to ytterbium-148, which itself is not long-lived: It has a half-life of 250 milliseconds.

According to PhysicsWorld, it is possible to make lutetium-148, which lasts slightly longer than lutetium-149.