Radioluminescence luminosity over their working life. The latest generation of radioluminescent materials is based on tritium, a radioactive isotope of hydrogen with half-life of 12.32 years that emits very low-energy beta radiation. It is used on wristwatch faces, gun sights, and emergency exit signs. The tritium gas is contained in a small glass tube, coated with a phosphor on the inside. Beta particles emitted by the tritium strike the phosphor coating and cause it to fluoresce, emitting light, usually yellow-green. Tritium is used because it is believed to pose a negligible threat to human health, in contrast to the previous radioluminescent
On-Line Isotope Mass Separator On-Line Isotope Mass Separator The On-Line Isotope Mass Separator, also known as the ISOLDE Radioactive Ion Beam Facility, is a facility located at CERN on the PS Booster. It started operating in 1967 and was rebuilt twice with major upgrades in 1974 and 1992. ISOLDE (Isotope Separator On Line DEtector) is dedicated to producing radioactive nuclei for a number of applications covering nuclear, atomic, molecular and solid-state physics, but also biophysics and astrophysics. The large variety of available species allows the systematic study of atomic and nuclear properties and exotic decays far from the line of stability. As of 2006,