Direct evidence revealed for rare pulsing pear-shapes in Gadolinium nuclei

The study, published in Physical Review Letters, provides definitive proof of a strong collective ‘octupole excitation’ in the nucleus of Gadolinium-150, a long-lived radioactive isotope of this rare-earth element, which is used in applications such as superconductors, nuclear power operations and MRI contrast materials.  

The experimental signature is interpreted as the protons and neutrons inside the atomic nucleus vibrating in a coordinated pattern, resulting in a pulsing, asymmetric, pear-shaped structure. 

Using high-precision gamma-ray measurements of emissions from the nucleus of Gadolinium-150, researchers were able to observe the signature fingerprints of these incredibly tiny pear-shaped structures. Atomic nuclei are so small that even the most advanced optical microscopes are unable to detect them, but information on their structure can be obtained by measuring the characteristic (gamma-ray) emissions as they relax. 

The findings open a new window into the quantum world, providing what can be described as a ‘femtoscope’ – a high-precision ‘nuclear microscope’ – that allows scientists to look deep into the subatomic structures that shape our universe.  

The results also represent a unique challenge to current theoretical models, which struggle to explain how these shapes can arise from complex interactions of the protons and neutrons which make up the Gadolinium-150 nucleus.