Silicon-34’s core has proton shortage in its center
Scientists have found the first experimental evidence that an atomic nucleus can harbor bubbles.
The unstable isotope silicon-34 has a bubblelike center with a paucity of protons, scientists report October 24 in Nature Physics. This unusual “bubble nucleus” could help scientists understand how heavy elements are born in the universe, and help scientists find new, ultraheavy stable isotopes.
In their quirky quantum way, protons and neutrons in a nucleus refuse to exist in only one place at a time. Instead, they are spread out across the nucleus in nuclear orbitals, which describe the probability that each proton or neutron will be found in a particular spot. Normally, due to the strong nuclear force that holds the two types of particles together, nuclei have a fairly constant density in their centers, regardless of the number of protons and neutrons they contain. In silicon-34, however,