A new type of atomic nucleus discovered in the Accelerator Laboratory of the University of Jyväskylä belongs to the rarest naturally occurring element

Astatine is a fast-decaying, and therefore rare element. It has been estimated that in the Earth’s crust there is no more than one tablespoon of astatine. An experiment performed in the Accelerator Laboratory of University of Jyväskylä, Finland, has succeeded to produce a previously unknown atomic nucleus, 190-Astatine. The new isotope was produced in the fusion of 84Sr beam particles and silver target atoms. The isotope was detected among the products by using the detectors of RITU recoil separator. 

New nucleus emits alpha particles

The new nuclei decay via alpha decay towards more stable isotopes. Alpha decay is a common decay mode of heavy nuclei.

- The studies of new nuclei are important for understanding the structure of atomic nuclei and the limits of known matter, says Doctoral Researcher Henna Kokkonen from the Department of Physics, University of Jyväskylä.

The study is a part of master’s thesis

New discovery was made by Henna Kokkonen, recently graduated Master of Science. The study was a part of her master’s thesis. It is uncommon that the results of master’s thesis are published in peer reviewed journal, such as Physical Review C, not to mention that it reports a new isotope.

- In my thesis, I analysed experimental data among which the new isotope was found. During my thesis process and summer internships I got to know the Nuclear Spectroscopy group’s work. Now I am very happy to work in the group towards my PhD degree. 

Henna Kokkonen moved five years ago to Jyväskylä from Juva, south-eastern Finland, to study physics and now she continues her studies as a Doctoral Researcher in the Accelerator Laboratory of University of Jyväskylä.

Additional information:
•    Doctoral Researcher Henna Kokkonen, henna.e.kokkonen@jyu.fi
•    Academy Research Fellow Kalle Auranen, kalle.e.k.auranen@jyu.fi
•    The Nuclear Spectroscopy group: https://www.jyu.fi/science/en/physics/research/nuclear-and-accelerator-based-physics/nuclear-spectroscopy 
•    The Accelerator Laboratory: https://www.jyu.fi/science/en/physics/research/infrastructures/accelerator-laboratory 
•    Publication: Phys. Rev. C 107, 064312 (2023)
•    Link to article: https://doi.org/10.1103/PhysRevC.107.064312