Standardization of .sup.177Lu by means of 4[pi][beta]-[gamma] coincidence and anti-coincidence counting

The activity concentration of a .sup.177Lu solution was measured by the Laboratory of Radioactivity Standards in the Radioisotope Centre POLATOM. The solution was measured by means of 4[pi][beta](LS)-[gamma] coincidence and anticoincidence counting. Both methods gave consistent results of the activity concentration, a relative standard uncertainty of 0.24% was obtained, which is much smaller than the uncertainty of previous measurement performed within the scope of the international comparison CCRI(II)-K2.Lu-177 in 2009. To establish a more precise calibration factor of a 4[pi] ionization chamber for this isotope, the obtained result of activity concentration was used.