Sains Malaysiana 41(2)(2012): 233–236

Study of non-1/ν reaction nuclides using k₀ - Neutron Activation Analysis

at the Malaysian Nuclear Agency Research Reactor

(Kajian Tindak Balas Nuklid yang Tidak Mematuhi Hukum 1/ν Menggunakan k0- Analisis Pengaktifan

Neutron di Reaktor Penyelidikan Agensi Nuklear Malaysia)

Alireza Yavar & Khoo Kok Siong

School of Applied Physics, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor D.E. Malaysia

Sukiman Sarmani

Chemistry Programme, School of Chemical Sciences & Food Technology

Faculty Science and Technology, Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor D.E. Malaysia

Abdullah Khalik Wood

Analytical Chemistry Application Group, Industrial Technology Division

Malaysian Nuclear Agency (MNA), Bangi, 43000 Kajang, Selangor D.E. Malaysia

Received: 18 November 2010 / Accepted: 22 July 2011

ABSTRACT

The modified spectral index r(α); the Westcott gLu(Tn) factor and absolute neutron temperature Tn were determined for the handling of non-1/ν (n, γ) reaction based on the Westcott formalism using k0-neutron activation analysis (k0-NAA) method at the Malaysian Nuclear Agency (MNA) research reactor. The r(α) was determined by the bare bi-isotopic monitor method using measurement of radionuclides of 97Zr and 95Zr. The 176Lu as non-1/ν and 197Au as 1/ν monitors were utilized for determination of gLu(Tn). The r(α) and gLu(Tn) values ranged from 0.0715 to 0.1417 with a RSD of 15.24% and from 1.7832 to 2.0149 with a RSD of 3.58%, respectively. The accuracy of the method was evaluated based on the calculated absolute neutron temperature (Tn) value. The calculated average value of Tn was 40.56±9.32°C while the value reported by MNA was 40°C, which represents an acceptable level of consistency.

Keywords: Malaysian Nuclear Agency; neutron flux spectra; non-1/ν (n, γ) reaction nuclides; TRIGA MARK II reactor; Westcott formalism

ABSTRAK

Nilai indeks spektrum diubahsuai r(α); faktor Westcott gLu(Tn) dan suhu neutron mutlak Tn telah ditentukan menggunakan tindak balas yang tidak mematuhi hukum 1/ν (n, γ) berasaskan rumus Westcott, menggunakan kaedah k0-analisis pengaktifan neutron (k0-APN) di reaktor penyelidikan Agensi Nuklear Malaysia (ANM). Nilai r(α) telah ditentukan dengan kaedah monitor dwi-isotop menggunakan pembilangan bagi radionuklid 97Zr dan 95Zr. Pemonitor 176Lu yang tidak mematuhi hukum 1/ν dan pemonitor 197Au yang mematuhi hukum 1/ν digunakan sebagai penentuan gLu(Tn). Nilai r(α) dan gLu(Tn) yang diperoleh masing-masing berjulat 0.0715 hingga 0.1417 dengan Sisihan Piawai Relatif (RSD) ialah 15.24% dan julat 1.7832 hingga 2.0149 dengan RSD ialah 3.58%. Kejituan kaedah yang digunakan telah dinilai berdasarkan pengiraan suhu neutron mutlak (Tn). Nilai purata Tn yang diperoleh dalam kajian ini ialah 40.56±9.32°C manakala nilai yang dilaporkan oleh ANM ialah 40°C, membuktikan aras kebolehterimaan yang konsisten.

Kata kunci: Agensi Nukleur Malaysia; formula Westcott; Reaktor TRIGA Mark II; Spektrum fluks neutron; Tindakbalas nuklid tidak mematuhi hukum 1/ν

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*Corresponding author; email: khoo@ukm.my