Ytterbium-175 half-life determination

175Yb is a radionuclide that can be generated by neutron capture on 174Yb and whose decay properties make it useful for developing therapeutic radiopharmaceuticals. As happens with many of the emerging radionuclides medical uses in recent years, its nuclear data were determined decades ago are not thoroughly documented nor accurate enough metrological purposes. The last reference half-life value 4.185(1) days dates back to 1989, so redetermination was considered appropriate before standardization at Institute Radiation Physics (IRA, Lausanne, Switzerland) primary measurements laboratory. Three independent measurement methods used this purpose: ionization chamber (CIR, chambre d'ionization de référence), CeBr3 ?-ray detector digital electronics second analog single-channel analyzer (SCA) counting. obtained 4.1615(30) which shows 0.56% relative deviation (ENSDF 2004) supported detailed calculation associated uncertainty.