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The Miniball set-up at the REX-ISOLDE facility for studying the spectra of exotic short-lived nuclei

ISOLDE – Isotope Separator On-Line

An alchemical factory for nuclear physics

ISOLDE (On-Line Isotope Mass Separator) is a unique source of low-energy beams of radioactive isotopes - atomic nuclei that have too many or too few neutrons to be stable. The facility, located at the Proton-Synchrotron Booster (PSB), is like a small alchemical factory, changing one element to another, rather as the alchemists once imagined. It produces a total of more than 1000 different isotopes for a wide range of research. Up to now more than 600 isotopes of more than 60 elements - from helium to radium - have been produced, with half-lives down to milliseconds. Most of the experiments study the structure of the nucleus in different ways, but there are also experiments relevant to atomic physics, nuclear astrophysics, fundamental physics, solid-state physics and life sciences.

ISOLDE directs a beam of protons from the PSB onto special targets, yielding a wide variety of atomic fragments. Different components then extract the nuclei and separate them according to mass. The Radioactive beam EXperiment (REX) at ISOLDE accelerates the radioactive beams created in this way, increasing the range of possible experiments. Many of these use Miniball, a gamma-ray detector based on very pure germanium.

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