Understanding Nuclear Stability: Magic Numbers in Physics
Shutterstock/ktsdesign
A pivotal set of numbers has served as the foundation of nuclear physics research for decades, revealing how they stem from the quantum interplay of nuclear particles and forces.
Nearly 80 years ago, physicist Maria Goeppert Mayer discovered that atomic nuclei exhibit remarkable stability when they contain specific numbers of protons and neutrons, such as 50 or 82. Subsequent research has reinforced the existence of these “magic numbers,” which characterize the most stable and abundant elements in the universe.
Goeppert Mayer’s contemporaries introduced the concept that protons and neutrons occupy discrete energy levels or shells. While this shell model persists in explaining numerous nuclear physics experiments by treating each nucleus particle as independent, modern quantum theory contends that these particles engage in strong interactions.
Yao Jianming and researchers from Sun Yat-sen University in China have reconciled this discrepancy, revealing how magic numbers originate from these interactions.
According to Yao, the shell model does not derive intricate details of particle interactions. Instead, he and his team approached their calculations from first principles, elucidating how particles interact, cling together, and the energy required to separate them.
Yao likens the two models to images captured at differing resolutions: “Historically, researchers either modeled the system at low resolution or explored nuclear structure at high resolution. We applied contemporary methods to bridge these models.”
The team initiated their analysis with a high-resolution perspective, then deliberately blurred it at each calculation stage, observing how particle structures evolved.
The researchers noted that the symmetry of a particle’s quantum state shifts across a mathematical bridge. By graphing these state equations, they produced shapes showcasing various symmetries at different resolutions. This transformation led to a nuclear structure where nuclei are most stable when particles correspond to magic numbers.
Jean-Paul Ebelin from the French Alternative Energy and Atomic Energy Commission emphasizes that this study offers a theoretical exploration akin to a mathematical microscope, effectively mirroring experimental observations. “Nature reveals a different facet depending on the observational resolution,” Ebelin notes.
The identified symmetry alterations correlate with effects noted in Albert Einstein’s special theory of relativity, as Ebelin points out, enhancing our understanding of how magic numbers unify various elements of nuclear theory.
To date, researchers have validated their theoretical findings on a specific type of tin, known for its double magic property due to possessing 50 protons and 82 neutrons, along with several other nuclei. Looking ahead, Yao expresses intentions to extend their analysis to heavier and typically unstable nuclei, exploring how these are formed during supernova events and the collision of neutron stars.
Topics:
Source: www.newscientist.com
