Trapping of relatively short-lived radioactive ¹⁴⁶Eu in a Paul trap

A new technique has been developed wherein one of the relatively short lived isotopes of europium (¹⁴⁶Eu, Half life = 4.61 days) has been generated by decay of parent ¹⁴⁶Gd atoms and the ions are confined in a Paul trap for spectroscopic studies. Studies of the mass dependent ion oscillation frequencies show that the ions trapped have a mass number 146 amu and this was confirmed by similar measurements carried out on trapped barium and potassium ions. From calculations of thermal ionization probabilities based on the Langmuir–Saha equation and the number of trapped ions estimated from ion response signal, the approximate number of the different isobars (of mass number 146) trapped, has been evaluated. We also present simulations of the evolution of laser-induced fluorescence photons of the trapped ¹⁴⁶Eu ions, wherein a pulsed laser is used to excite the resonance ⁹S₄ - ⁹P₅ transition, which rapidly decays to the metastable ⁹D₄₋₆ states emitting fluorescence photons. (paper)