Continuous Signal-Based Neutron Noise Measurements Demonstrated as Viable Alternative to Pulse-Counting
A new feasibility study shows that analyzing the continuous detector current — rather than counting individual pulses — can accurately measure key neutron kinetic parameters in nuclear reactors even at high detection rates. Traditional pulse-counting methods break down at high count rates due to dead-time and pile-up effects, problems that the continuous-signal approach avoids through pulse-shape correction techniques. The findings, validated at two research reactors, could improve reactor diagnostics and safety monitoring in high-flux environments.
Researchers have demonstrated the feasibility of using continuous detector current signals for neutron noise analysis, addressing longstanding limitations of conventional pulse-counting methods in nuclear reactor diagnostics. Pulse-counting techniques suffer from dead-time and pile-up distortions at high detection rates, making them unreliable for measuring the prompt neutron decay constant (α-parameter) under demanding conditions. The new approach applies a stochastic model of the detector current to derive Rossi- and Feynman-type formulations, and corrects for pulse-shape distortions using either detector pairs or deconvolution via inverse Fourier and Wiener filtering. Simulations confirmed accurate α-parameter estimation at count rates where pulse-counting fails, and also enabled evaluation of significantly higher α values than previously accessible. Experimental validation was carried out at two research reactors — KUCA and BME TR — where continuous and deconvolved signals produced unbiased results despite dead-time effects and electronic artifacts. The study, submitted to the journal Progress in Nuclear Energy, establishes the continuous-signal method as a practical alternative for high-rate reactor noise diagnostics.
What's missing
The manuscript is a preprint submitted for peer review and has not yet been formally accepted, so findings remain subject to revision.
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- arXiv physicsCenter
Feasibility demonstration of continuous signal-based neutron noise measurements by experiments and simulations
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