Open refereed paper reveals how to study unstable radioactive nuclei's dual traits

November 16, 2016, Springer

Radioactive nuclides, found within an atom's core, all share a common feature: they have too many or too few neutrons to be stable. In a new review published in EPJ A, Maria Jose Borges and Karsten Riisager explain how overcoming technical difficulties in accelerating such radioactive nuclei beams can help push back the boundaries of nuclear physics research. This fascinating topic is the first EPJ A paper to be subjected to an open referee process, whereby the referee's comments are included.

The authors outline how the new CERN project HIE-ISOLDE will reach the energy levels needed to make two nuclei overcome the electric repulsion between them - referred to as the Coulomb barrier. This means that it will be possible to design experimental tools to explore both single-particle and collective degrees of freedom. This will improve our understanding of the unique duality in the degrees of freedom, which no other state of matter exhibits.

The radioactive nuclei are generated at CERN, near the Franco-Swiss border, via the Isotope mass Separator On-Line facility (ISOLDE), which is a unique source of low-energy beams. Specifically, the HIE-ISOLDE project aims to raise the maximum energy of accelerated particles beyond the Coulomb barrier, to more than 10 megaelectron volts / atomic mass units (MeV/u).

In this review, the authors outline of the history of the project and then explain the nature of the superconducting linear accelerator used in HIE-ISOLDE, giving further details on how physicists plan to improve the beam quality and intensity. Subsequently, the team is also planning to add superconducting cavities allowing for a deceleration of the beams to better control optimum energy for each reaction and tailor them, for example, to conditions found in the stars for astrophysics studies. Many other applications are pending and the review offers a sample of planned studies.

Ultimately, physicists aim to have a "dial-a-radioactive-nuclei beam" of the same quality as stable nuclei beams.

Explore further: CERN: A milestone toward a higher-energy nuclear physics facility

More information: M.J.G. Borge and K. Riisager (2016), HIE-ISOLDE, the project and the physics opportunities, European Physical Journal A 52: 334, DOI: 10.1140/epja/i2016-16334-4

Related Stories

WITCH hunt nearing end at CERN

October 30, 2015

This Halloween, meet CERN's very own WITCH – an experiment at ISOLDE, the laboratory's nuclear facility.

Heavy barium nuclei prefer a pear shape

June 7, 2016

Certain heavy barium nuclei have long been predicted to exhibit pear-like shapes. However, until recently, experimental confirmation had been impossible to achieve as these nuclei typically only live for a few seconds. The ...

Recommended for you

New thermoelectric material delivers record performance

January 17, 2019

Taking advantage of recent advances in using theoretical calculations to predict the properties of new materials, researchers reported Thursday the discovery of a new class of half-Heusler thermoelectric compounds, including ...

Zirconium isotope a master at neutron capture

January 17, 2019

The probability that a nucleus will absorb a neutron is important to many areas of nuclear science, including the production of elements in the cosmos, reactor performance, nuclear medicine and defense applications.


Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.