Correction

This article refers to:

Uncertainty reduction of sodium void reactivity using data from a sodium shielding experiment

Article Title: Uncertainty reduction of sodium void reactivity using data from a sodium shielding experiment

Authors: Shuhei Maruyama, Tomohiro Endo, Akio Yamamoto

Journal: Journal of Nuclear Science and Technology

Bibliometrics: Volume 61, 2024- Issue 1, pages 31-43.

DOI: https://doi.org/10.1080/00223131.2023.2244512

It has been noted by the authors that the paper was published with errors.

As a result of the error corrections, the reduction effect of the relative uncertainty on the JOYO MK-I SVR measurement in Figure 8, which is the main result of this paper, has been corrected as shown below. The a posteriori total uncertainty was slightly changed from 4.7% (before correction) to 4.8% (after correction). Even after the correction, the uncertainty induced by the Na-23 elastic scattering cross-section was reduced to the same level as the other uncertainties by the cross-section adjustment. Therefore, the correction did not affect the original conclusions of the article.

Figure 4. Relative sensitivities for different measurements with respect to Na-23.

The change in the results for Na-23 in Figure 8 was due to the missing of the (–1)${ }^l$ factor for the terms proportional to ${\mathrm{\Sigma }}_{\mathrm{s},l}$ in the sensitivity coefficient calculations. As a result of this correction, the signs of the sensitivity coefficients for the $\bar{\mu }$ (odd moments) were reversed, as shown in Figure 4. The sensitivity coefficients with respect to the $P_0$ scattering cross-section were also affected by the correction, since ${\mathit{\sigma }}_{\mathrm{s}l}$ depends not only on the scattering angle distribution, but also on the $P_0$ scattering cross-section (e.g., for the P₁ elastic scattering cross-section, ${\mathit{\sigma }}_{\mathrm{s}1}=\bar{\mu }{\mathit{\sigma }}_{\mathrm{s}0}$). The correction of the sensitivity coefficients affected the results of the cross-section adjustment (data assimilation). As a result, Figure 8 has been modified.

Figure 6. Results of cross-section adjustment.

The corrections for the other table and figures other than Figure 8 (i.e., Figure 4, 6, 7, 9, and Table 5), which are less relevant to the conclusion, are listed together at the end.

Figure 7. Reduction rate of contribution to relative uncertainties for SVRs.

Figure 8. Uncertainty reduction in a JOYO MK-I SVR measurement (void pattern: [000]).

Figure 9. Relationship between the uncertainty reduction rate for Na-23 elastic scattering cross-section and the ratio of SVR components.

Table 5. Evaluation results of the effectiveness of measurement data against JOYO MK-I SVR.

Shielding thickness	indicies	Cd BB	3” BB	6” BB	12” BB	Mod BB	NE-213
30”	c^2	0.11	0.07	0.39	0.13	-	-
	f	0.05	0.02	0.03	0.24	-	-
	Δv/v	0.01	0.00	0.01	0.03	-	-
60”	c^2	0.22	0.00	0.34	0.13	0.31	-
	f	0.08	0.02	0.13	0.38	0.46	-
	Δv/v	0.02	0.00	0.04	0.05	0.14	-
120”	c^2	0.16	0.28	0.32	0.28	0.24	0.02
	f	0.24	0.36	0.49	0.56	0.84	0.77
	Δv/v	0.04	0.10	0.16	0.16	0.20	0.01
150”	c^2	0.22	0.28	0.31	0.30	0.22	-
	f	0.49	0.59	0.64	0.67	0.88	-
	Δv/v	0.11	0.16	0.20	0.20	0.19	-
180”	c^2	0.24	0.28	0.30	0.29	0.19	-
	f	0.66	0.71	0.75	0.76	0.88	-
	Δv/v	0.16	0.20	0.22	0.22	0.17	-

The authors would like to apologize for this oversight.