Results suggests titanium-48’s nuclear structure changes when observed at varying distances

The world around us is made up of particles invisible to the naked eye, yet physicists continue to gain insight into this mysterious realm. Published in Physics Review C Researchers at Osaka Metropolitan University Graduate School have shown that the structure of an atomic nucleus likely changes depending on how far the protons and neutrons are from the center of the nucleus.

OMU graduate student Maito Okada, Associate Professor Wataru Horiuchi, and Professor Naoyuki Itagaki from the Graduate School of Science said, Theoretical model Existing Experimental Data Determine whether titanium-48, the most common isotope of titanium with 22 protons and 26 neutrons, has a shell model structure or an α-cluster (alpha cluster) structure.

The shell model is symmetric, but the α-cluster structure is Alpha Particles In the outer regions Nuclearforming an asymmetric configuration. An alpha particle is the equivalent of helium with two protons and two neutrons. In alpha decay, this particle is emitted. For example, titanium-48 becomes calcium-44 when such decay occurs.

The OMU team calculated the effect of high-energy accelerated protons and alpha particles bombarding titanium-48, which proton The impact of alpha particles on atomic nuclei reflects the structure near the surface of the target nucleus, whereas the impact of alpha particles on atomic nuclei reflects the structure of the outer regions.

This result suggests that titanium-48 changes from a shell model structure to an α-cluster structure depending on the distance from the core center.

“This result overturns our conventional understanding of nuclear structure and is expected to provide a clue to understanding the alpha decay process that occurs in heavy nuclei, which has remained unexplained for about 100 years,” said Professor Horiuchi, referring to Gamow’s theory of nuclear decay.

“In the future, we would like to expand on the results of this research and attempt to solve problems related to heavier atomic nuclei.”