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Development of an embedded FPGA-based data acquisition system dedicated to zero power reactor noise experiments

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Arkani M. , Khalafi H. , Vosoughi N.

Metrology and Measurement Systems

2014

tom Vol. 21, nr 3

433--446

An embedded time interval data acquisition system (DAS) is developed for zero power reactor (ZPR) noise experiments. The system is capable of measuring the correlation or probability distribution of a random process. The design is totally implemented on a single Field Programmable Gate Array (FPGA). The architecture is tested on different FPGA platforms with different speed grades and hardware resources. Generic experimental values for time resolution and inter-event dead time of the system are 2.22 ns and 6.67 ns respectively. The DAS can record around 48-bit x 790 kS/s utilizing its built-in fast memory. The system can measure very long time intervals due to its 48-bit timing structure design. As the architecture can work on a typical FPGA, this is a low cost experimental tool and needs little time to be established. In addition, revisions are easily possible through its reprogramming capability. The performance of the system is checked and verified experimentally.

Application of a neuro-fuzzy model for neutron activation analysis (NAA)Sb

100%

Khalafi H. , Terman M. S. , Rahmani F.

Nukleonika

2011

tom Vol. 56, No. 1

17-21

Neutron activation analysis (NAA) is a precise chemical multielemental method of analysis which is satisfactorily used for qualitative and quantitative analyses. Repeated irradiation is needed because of mal-determination of some elements due to peak overlap in qualitative analysis. In this study, NAA procedure has been modified using a neuro-fuzzy model to avoid repeated irradiation based on multilayer perceptrons network trained by the Levenberg-Marquardt algorithm. This method increases the precision of spectrum analysis in the case of strong background and peak overlap.

Development and Experimental Validation of a Correlation Monitor Tool Based on the Endogenous Pulsed Neutron Source Technique

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Arkani M. , Khalafi H. , Vosoughi N. , Khakshournia S.

Metrology and Measurement Systems

2017

tom Vol. 24, nr 3

441--461

A correlation measuring tool for an endogenous pulsed neutron source experiment is developed in this work. Paroxysmal pulses generated by a bursts of neutron chains are detected by a 10-kbit embedded shift register with a time resolution of 100 ns. The system is implemented on a single reprogrammable device making it a compact, cost-effective instrument, easily adaptable for any case study. The system was verified experimentally in the Esfahan heavy-water zero power reactor (EHWZPR). The results obtained by the measuring tool are validated by the Feynman-α experiment, and a good agreement is seen within the boundaries of statistical uncertainties. The theory of the methods is briefly initiated in the text. Also, the system structure is described, the experimental results and their uncertainties are discussed, and neutron statistics in EHWZPR is examined experimentally.

An improved formula for dead time correction of G-M detectors

100%

Arkani M. , Khalafi H. , Arkani M.

Nukleonika

2013

tom Vol. 58, No. 4

533--536

Different analytical formulae have been described in the literature to modify response of Geiger-Müller (G-M) detectors. In this work, improvement of a previously proposed dead time correction formula was investigated. A set of experimental data of a decaying source was the basis of the analysis. A general agreement is seen with the experimental data. The result was compared with those obtained by the original work. Numerical aspects were also examined.