A team of international scientists together with researchers from the Lawrence Livermore National Laboratory (USA) have discovered five new atomic nuclei: an isotope for berkelium (Bk), neptunium (Np) and uranium (U) and two isotopes of americium ( A.M).
An isotope is an atom that belongs to the same chemical element with the same atomic number; the exception is its atomic mass, which is different. So far, the periodic table of known elements contains more than 3,000 isotopes (there are still a few thousand more to discover) of 114 chemical elements.
The researchers were delving into the development of new synthesis methods for superheavy elements (or transactinids) when they discovered that these isotopes had fewer neutrons and were also lighter than the known isotopes of their respective chemical elements, making them nuclei. exotic.
“When you realize that natural uranium has 146 neutrons and this new isotope only has 124 neutrons , it shows how much we have to learn about the nuclear structure and the forces that hold the nucleus together,” explains study co-author Dawn Shaughnessy.
To achieve this finding, the scientists fired at a 300-nanometer-thick sheet of curium with accelerated calcium nuclei; the atomic nuclei of the two elements touched formed a system composed of a very short time; However, the two nuclei exchanged a number of their proton and neutron building blocks before the system broke down, generating different isotopes accordingly. By analyzing all the decay products detected in the experiment, they were able to identify the five new atomic nuclei.
The study has been published in the journal Physics Letters B.
