Uncertainties in the anti-neutrino production at nuclear reactors

Abstract

Anti-neutrino emission rates from nuclear reactors are determined from thermal power measurements and fission rate calculations. The uncertainties in these quantities for commercial power plants and their impact on the calculated interaction rates inνe detectors is examined. We discuss reactor-to-reactor correlations between the leading uncertainties, and their relevance to reactorνe experiments.

Measurement of electron antineutrino oscillation based on 1230 days of operation of the Daya Bay experiment

“…A systematic uncertainty of 0.5% was attributed to these data [57,61], and assumed to be uncorrelated between reactors. (This assumption was conservative, given that the correlated component cancels in the near-far comparison of antineutrino rates.)…”

“…These data were also obtained through agreement with the reactor company, and validated using an independent simulation of the reactors. An uncertainty of 5% was assumed, uncorrelated between reactors, but with a correlation among isotopes taken from [57].…”

Experimental Neutrino Physics: Final Report

“…Since the amount of data taken with one or two cores at intermediate power is small, this uncertainty is used for the mean power of both cores. This is smaller than the typical uncertainty for PWRs of 0.7% [35] and reflects optimizations in the pipe geometry of the secondary loop, as well as great care taken to understand the sensor uncertainties, including full-scale test stands for the most critical sensors. The mean cross section per fission is effectively a spectrum averaged cross section.…”

New Monte Carlo-based method to evaluate fission fraction uncertainties for the reactor antineutrino experiment

“…The uncertainty of fission fraction of different isotopes was shown in table 2. [1]. 0.58% Xubo Ma et al [5] 0.60% data from the Daya Bay experiment were used to calculate the expected average daily antineutrino flux at one detector.…”

“…The verification and validation of the code simulation was done by comparison of isotropic concentration with the experiment results. The fission fraction coefficients between isotopes [1] was approximately studied using 159 comparisons of fuel element samples taken from ten PWRs and BWRs, modeled by a variety of core simulation codes, because these isotopic concentration comparisons only give indirect information on the uncertainty in the number of fissions fraction. The correlation coefficients was also studied by using fission fraction of each isotopes directly [5].…”