Thermal neutron flux measurement at pneumatic transfer system (pts) of reactor triga puspati (rtp) using neutron activation analysis (naa) / Nur Zarifah Zahali

PUSPATI TRIGA Reactor is the only research reactor in Malaysia started its
operation in 1982. It has conducted many research and analysis in nuclear and
medical science. One of them is neutron flux measurement analysis by using
Neutron Activation Analysis (NAA). The sample used is Au-197. The samples
are prepared in the form of bare Aurum (Au) and Aurum covered with Cadmium
(Cd). Irradiation of samples takes place at Pneumatic Transfer System (PTS) of
PUSPATI TRIGA Reactor. After irradiation process, the counting of sample
which is the decay is measured by using high-purity germanium (HPGe) gamma
detector. The efficiency of detector will determine the precision of the neutron
flux. When the distance of detector is increased the Aurum efficiency is
decreased exponentially. Neutron Activation Analysis is the method used in
nuclear field to determine the concentration of element in a wide amount of
materials. The neutrons will bombard the elements or samples caused activity of
radioactive samples can be determined. The formula of neutron flux is used to
determine the thermal flux conducted in PTS. The experimental result give out
the thermal neutron flux at PTS is 5.75 x 1011 ncm-2 s-1 . It is quite accurate to
calculated result which is at 6.0 x 1011 nem-25-1 .