Characterization of an ²⁴¹Am-Be neutron irradiation facility at Institute for Nuclear Science and Technology

Tran Ngoc Toan1, Chu Vu Long2, Bui Duc Ky2, Nguyen Duc Kien3, Nguyen Duc Tam3
1 Vietnam Atomic Energy Institute, 59 Ly Thuong Kiet, Hanoi, Vietnam
2 Institute for Nuclear Science and Technology, 179 Hoang Quoc Viet, Hanoi, Vietnam
3 Hanoi University of Natural Science, Nguyen Trai, Hanoi, Vietnam

Main Article Content

Abstract

An automated panoramic irradiator with a 241Am-Be neutron source of 5 Ci is installed in a bunker-type medium room at the Institute for Nuclear Science and Technology (INST) for calibration of neutron devices. Bonner Sphere Spectrometer (BSS) formed by 6 spheres plus bare detector, with cylindrical, almost point like, 6LiI(Eu) scintillator and 2 different spectral unfolding FRUIT and BUNKIUT codes are used to characterize the neutron field in different measurement points along the irradiation bench. The neutron field is also simulated by MCNP5 software and compared with measurements performed by the BSS. The paper shows the main results obtained in terms of neutron spectra at fixed distances from the source as well as their neutron fluence rate (total and direct) and ambient dose equivalent rate. These values measured by the BSS with two unfolding FRUIT and BUNKIUT codes are in good agreement with that of simulated by MCNP5 within 10%.

Article Details

References

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