Resonance analysis of ^151,153Eu from neutron capture cross section measurements in the energy range from 1 to 20 eV

Figures & data

Figure 1. Evaluated values in JENDL-4.0, ENDF/B-VII.1, and JEFF-3.2 for the ¹⁵¹Eu in the energy from 2.5 to 8.5 eV.

Figure 2. Experimental arrangement for the capture cross section measurement.

Table 1. Characteristics of samples

Sample	^151Eu	^153Eu	^10B	^natC
Chemical form	Eu2O3	Eu2O3	^10B	C
Isotope	^151Eu: 97.6 (±0.2)%	^153Eu: 99.71% (±0.06)%	^10B: 96.98%	^12C: 98.93%
composition	^153Eu: 2.4 (±0.2)%	^151Eu: 0.29% (±0.06)%	^11B: 3.02%	^13C: 1.07%
Weight (g)	0.106	0.111	2.92	8.64
Thickness (atoms/b)	1.11 × 10^−4	1.16 × 10^−4	5.25 × 10^−2	1.32 × 10^−1
Size	1.80 × 1.80 cm^2	1.80 × 1.80 cm^2	1.80 × 1.80 cm^2	1. 80 × 1.80 cm^2

Table 2. Chemical impurities in the ¹⁵¹Eu and ¹⁵³Eu samples

Impurity	^151Eu sample (ppm)	^153Eu sample (ppm)
K	<500	60
Ca	<100	40
Mg	<40	<30
Fe	50	<30
Al	<50	<50
Si	<100	<60
Cr	<70	<50
Ni	30	70
Cu	<100	<60
Mn	<20	<10
Pb	10	<10
Sn	50	60
Sm	<100	260
Nd	200	660
Gd	200	<100
Ge	<20	–
Ga	50	–

Figure 3. BGO assembly used in the present measurement.

Figure 4. Block diagram for the present measurements using the BGO assembly.

Table 3. List of measuring times

Samples	Measurements	Measuring time (h)
^151Eu	Foreground	5.9
^153Eu	Foreground	17.4
Al foil	Background	3.5
^10B	Foreground	1.5
^10B+filters	Foreground	0.6
^10B case	Background	1.6
^natC	Foreground	0.5
Blank	Background	0.2

Figure 5. Flowchart of data analysis procedures.

Figure 6. Correction factors for the impurity in the ¹⁵¹Eu and ¹⁵³Eu samples.

Figure 7. Correction factors for the neutron self-shielding and multiple-scattering in the ¹⁵¹Eu and ¹⁵³Eu samples.

Table 4. Experimental uncertainties

Type of uncertainties	Uncertainty (%)
Statistical error	^151Eu	^153Eu
0.005−0.01 eV	2–5	2–5
0.01−1 eV	2–6	2–11
1−10 eV	3–32	2–33
10−100 eV	4–153	3–337
Systematic error	^151Eu	^153Eu
Uncertainty of the ^10B(n,αγ) reaction cross section	0.2–1.6	0.2–1.6
Uncertainty of sample thickness	2.4	2.4
Correction uncertainty of the isotopic impurity in the sample	0.1–5.8	0.1–7.8
Effects of the chemical impurity and moisture in the sample	0.1–0.8	0.1–1.6
Correction uncertainty of neutron multiple-scattering and self-shielding	2.1–3.5	1.9–3.5
Normalization	–	–

Figure 8. Obtained capture cross sections of ¹⁵¹Eu in the energy range from 1 to 10 eV.

Figure 9. Obtained capture cross sections of ¹⁵³Eu in the energy range from 1 to 10 eV.

Table 5. Obtained resonance parameters for the ¹⁵¹Eu compared with the JENDL-4.0 and the Leinweber's parameters

JENDL-4.0	Leinweber [8]						Present (^151Eu)				I = 2.5
En (eV)	Гγ (meV)	Гn (meV)	En (eV)	Гγ (meV)	Гn (meV)	Ratio^a	En (eV)	Гγ (meV)	Гn (meV)	Ratio^b	J
2.71	97.00	0.22	2.72	90 ± 1	0.21 ± 0.01	0.95 ± 0.05	2.71 ± 0.01	123.04 ± 4.75	0.25 ± 0.01	1.14 ± 0.05	3
3.36	97.00	1.10	3.37	87 ± 0.5	2.62 ± 0.01	2.38 ± 0.01	3.37 ± 0.01	119.15 ± 2.96	2.28 ± 0.03	2.07 ± 0.03	2
3.71	89.00	0.69	3.71	91 ± 1	1.04 ± 0.01	1.51 ± 0.01	3.71 ± 0.01	106.80 ± 4.20	0.73 ± 0.02	1.06 ± 0.03	3
4.78	93.00	0.15	4.80	66 ± 5	0.04 ± 0.01	0.27 ± 0.07	4.78 ± 0.01	100.87 ± 9.22	0.06 ± 0.01	0.40 ± 0.07	3
5.38	108.00	0.23	5.38	79 ± 2	0.16 ± 0.01	0.70 ± 0.04	5.39 ± 0.01	132.84 ± 9.93	0.32 ± 0.02	1.39 ± 0.09	2
5.98	100.00	0.41	5.98	110 ± 3	0.21 ± 0.01	0.51 ± 0.02	5.96 ± 0.01	129.89 ± 9.28	0.40 ± 0.02	0.98 ± 0.05	2
7.05	92.00	0.04	7.01	82 ± 4	0.41 ± 0.02	10.25 ± 0.50	7.00 ± 0.01	97.98 ± 8.51	0.32 ± 0.02	8.00 ± 0.50	3
7.29	88.00	1.89	7.23	85 ± 3	1.74 ± 0.03	0.92 ± 0.02	7.22 ± 0.01	99.30 ± 7.33	1.59 ± 0.08	0.84 ± 0.04	3
7.44	85.00	2.03	7.43	83 ± 1	2.75 ± 0.02	1.35 ± 0.01	7.42 ± 0.01	119.11 ± 5.59	4.05 ± 0.14	2.00 ± 0.07	2
9.07	104.00	1.30	9.07	84 ± 3	0.91 ± 0.01	0.70 ± 0.01	9.07 ± 0.01	143.93 ± 8.46	1.18 ± 0.04	0.91 ± 0.03	2
10.47	91.00	2.48	10.46	100	2.88 ± 0.01	1.16 ± 0.01	10.45 ± 0.01	123.50 ± 6.26	3.24 ± 0.08	1.31 ± 0.03	2
10.94	98.00	0.57	10.95	100	0.36 ± 0.01	0.63 ± 0.02	10.97 ± 0.01	114.17 ± 9.74	0.45 ± 0.03	0.79 ± 0.05	3
12.23	88.00	1.09	12.20	100	1.11 ± 0.01	1.02 ± 0.01	12.20 ± 0.01	104.29 ± 8.60	1.27 ± 0.07	1.17 ± 0.06	2
–	–	–	12.52	100	0.87 ± 0.02	–	12.48 ± 0.02	100.87 ± 9.57	0.92 ± 0.07	–	3
12.64	88.00	2.06	12.70	100	2.04 ± 0.03	0.99 ± 0.01	12.69 ± 0.01	108.85 ± 7.82	1.95 ± 0.08	0.95 ± 0.04	3
13.66	115.00	0.53	13.68	100	0.39 ± 0.01	0.74 ± 0.02	13.69 ± 0.01	122.70 ± 11.05	0.78 ± 0.05	1.47 ± 0.09	2
14.76	76.00	2.30	14.76	100	3.13 ± 0.02	1.36 ± 0.01	14.76 ± 0.01	93.43 ± 7.52	3.10 ± 0.11	1.35 ± 0.05	2
15.18	79.00	2.44	15.19	100	3.23 ± 0.02	1.32 ± 0.01	15.19 ± 0.01	104.34 ± 7.86	3.63 ± 0.12	1.49 ± 0.05	2
17.75	104.00	1.16	17.73	100	1.62 ± 0.02	1.40 ± 0.02	17.73 ± 0.01	121.98 ± 9.73	1.50 ± 0.07	1.29 ± 0.06	3
19.10	133.00	4.42	19.11	100	4.68 ± 0.01	1.06 ± 0.01	19.10 ± 0.01	177.05 ± 8.77	5.80 ± 0.15	1.31 ± 0.03	3

^a Ratio of the Leinweber's neutron width to the JENDL-4.0 neutron width.

^b Ratio of the present's neutron width to the JENDL-4.0 neutron width.

Table 6. Obtained resonance parameters for the ¹⁵³Eu compared with the JENDL-4.0 and the Leinweber's parameters

JENDL-4.0	Leinweber [8]						Present (^153Eu)				I = 2.5
En (eV)	Гγ (meV)	Гn (meV)	En (eV)	Гγ (meV)	Гn (meV)	Ratio^a	En (eV)	Гγ (meV)	Гn (meV)	Ratio^b	J
1.73	90.00	0.05	1.72	94.4 ± 0.6	0.07 ± 0.01	1.40 ± 0.20	1.72 ± 0.01	108.42 ± 6.28	0.05 ± 0.01	1.00 ± 0.20	3
2.46	91.00	1.03	2.46	96 ± 0.4	1.18 ± 0.01	1.15 ± 0.01	2.46 ± 0.01	137.54 ± 1.86	0.82 ± 0.01	0.80 ± 0.01	3
3.29	98.00	1.09	3.29	96.8 ± 0.3	1.21 ± 0.01	1.11 ± 0.01	3.29 ± 0.01	126.94 ± 2.65	0.95 ± 0.01	0.87 ± 0.01	2
3.94	93.00	0.94	3.94	94.8 ± 0.4	1.41 ± 0.01	1.50 ± 0.01	3.94 ± 0.01	126.43 ± 2.91	0.80 ± 0.01	0.85 ± 0.01	3
4.75	96.00	0.04	4.77	97 ± 4	0.03 ± 0.01	0.75 ± 0.25	4.80 ± 0.01	100.54 ± 9.77	0.05 ± 0.01	1.25 ± 0.01	3
6.16	109.00	0.54	6.16	100.2 ± 0.6	0.55 ± 0.01	1.02 ± 0.02	6.15 ± 0.01	142.40 ± 6.32	0.56 ± 0.01	1.04 ± 0.02	3
8.85	114.00	3.00	8.86	91 ± 0.5	5.01 ± 0.02	1.67 ± 0.01	8.85 ± 0.01	144.32 ± 4.00	2.73 ± 0.04	0.91 ± 0.01	3
11.61	96.00	3.44	11.62	110	3.64 ± 0.02	1.06 ± 0.01	11.61 ± 0.01	146.96 ± 4.97	3.15 ± 0.05	0.92 ± 0.01	3
12.45	90.00	0.12	12.45	110	0.14 ± 0.01	1.17 ± 0.08	12.40 ± 0.02	91.34 ± 9.05	0.13 ± 0.01	1.08 ± 0.08	3
13.22	96.00	0.27	13.23	110	0.51 ± 0.01	1.89 ± 0.04	13.20 ± 0.02	102.52 ± 9.84	0.31 ± 0.03	1.15 ± 0.11	3
15.26	96.00	0.36	15.30	110	0.40 ± 0.01	1.11 ± 0.03	15.27 ± 0.02	99.17 ± 9.72	0.39 ± 0.04	1.08 ± 0.11	2
16.33	96.00	0.02	16.13	110	0.01 ± 0.01	0.50 ± 0.50	16.33 ± 0.09	96.13 ± 9.61	0.02 ± 0.01	1.00 ± 0.01	3
16.73	89.00	1.16	16.73	110	1.76 ± 0.01	1.52 ± 0.01	16.70 ± 0.01	106.73 ± 8.17	1.21 ± 0.05	1.04 ± 0.04	3
17.60	96.00	0.39	17.57	110	0.33 ± 0.01	0.85 ± 0.03	17.50 ± 0.02	99.36 ± 9.63	0.43 ± 0.03	1.10 ± 0.08	3
18.01	92.00	3.63	18.02	110	4.18 ± 0.02	1.15 ± 0.01	18.01 ± 0.01	114.37 ± 6.87	3.63 ± 0.09	1.00 ± 0.02	3
18.73	100.00	3.38	18.76	110	3.75 ± 0.01	1.11 ± 0.01	18.75 ± 0.01	114.41 ± 8.17	3.28 ± 0.10	0.97 ± 0.03	2
20.02	101.00	11.40	20.02	110	18.90 ± 0.09	1.66 ± 0.01	20.01 ± 0.01	162.42 ± 5.83	13.91 ± 0.24	1.22 ± 0.02	2

^a Ratio of the Leinweber's neutron width to the JENDL-4.0 neutron width.

^b Ratio of the present's neutron width to the JENDL-4.0 neutron width.

Figure 10. Correction factors for the neutron self-shielding and multiple-scattering in the ¹⁵¹Eu sample using the JENDL-4.0 and the revised values in the energy range from 2.5 to 8.5 eV.

Figure 11. Neutron capture cross sections of ¹⁵¹Eu.

Figure 12. Neutron capture cross sections of ¹⁵¹Eu in the neutron energy region from 1 to 20 eV.

Figure 13. Neutron capture cross sections of ¹⁵³Eu.

Figure 14. Neutron capture cross sections of ¹⁵³Eu in the neutron energy region from 1 to 20 eV.

Leinweber G, Barry DP, Burke JA, et al. Europium resonance parameters from neutron capture and transmission measurements in the energy range 0.01-200 eV. Ann Nucl Energy. 2014;69:74–89.

 Web of Science ®Google Scholar