The experiments, published in Physical Review Letters, were performed using calcium 54, an unstable nucleus which has 20 protons and 34 neutrons. Through the experiments, the researchers showed that it exhibits strong shell closure, a situation with neutrons that is similar to the way that atoms with closed electron shells, such as helium and neon, are chemically inactive.
While it was once believed that the protons and neutrons were lumped together like a soup within the nucleus, it is now known that they are organized in shells. With the complete filling of a nuclear shell, often referred to as "magic number," nuclei exhibit distinctive attributes that can be probed in the laboratory. For example, a large energy for the first excited state of a nucleus is indicative of a magic number.
Studies - Neutron - Nuclei - Numbers - Numbers
Recent studies on neutron rich nuclei have hinted that new numbers need to be added to the known, canonical numbers of 2, 8, 20, 28, 50, 82, and 126.
Initial tests on calcium 54, also carried out at the RIBF in 2013, had already indicated that the number should exist. During the new experiment, the research focus shifted towards determining its actual strength. In the current experiment, the team around Sidong Chen directly measured the number of neutrons occupying the individual shells in calcium 54...
Wake Up To Breaking News!
Would you let a person who could only get a government job run your life? Well don't!