Finnish scientists have found new anomalies in the size of atomic nuclei when studying the properties of very unstable isotopes of copper. A study by scientists from the University of Jyväskylä is published in the journal Nature Physics.
The parameter of the charge radius is one of the most important in determining the boundaries of atomic nuclei and studying their structure. In fact, it shows how protons are distributed over an atom and where is the boundary at which the nucleus reflects charged particles.
Scientists have always believed that the charge radius almost grows along with the number of protons inside the nuclei. The only exception is the appearance of atoms with an even number of neutrons – their radius is larger than the nuclei of atoms with an odd number of neutrons.
There is still no full-fledged explanation of this phenomenon, however, some physicists believe that protons and neutrons inside the nucleus do not exist as separate particles, but rather as pairs connected to each other.
Finnish physicists from the University of Jyväskylä conducted research on such isotopes, simultaneously synthesizing them in the ISOLDE accelerator and measuring their charge radius.
In a new study, scientists measured the radius of the nuclei of single copper atoms, illuminating them with a laser and observing how their radiation spectrum changes. It turned out that the shifts of the lines during the glow of copper, which usually reflect the charge radius of the nucleus, were much slower than they should. While scientists have no explanation for this phenomenon, they say at the university.
These studies will further enable scientists to understand how protons and neutrons interact inside atomic nuclei.