A remotely operable quadrupole mass spectrometer based apparatus for fission gas analysis

Xenon and krypton are two fission gases that are produced in abundant yield in nuclear fission. For example, the yields of Xe and Kr in fast fission of 238U and 239Pu are about 25 and 20 atoms per hundred fissions, respectively. Retention of these gaseous fission products in the fuel matrix leads to swelling of the fuel during irradiation in a reactor resulting in fuel-clad mechanical interaction. This interaction limits the life of the fuel pin. A mixed carbide of uranium and plutonium is employed as fuel in the fast breeder test reactor at Kalpakkam. This fuel is more prone to swelling due to the face centered closed packed crystal structure of the carbide. Fission gas release analysis is one of the mandatory post-irradiation experiments in the examination of the irradiated fuel, before it is taken to higher burn-ups