IAEA Nuclear Data Section
Recommended data for
Time dependence of delayed neutron activity
Group Parameters


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Numerical data             Original, 1st set
                2nd set
Compiled data
Compilation by V. Piksaikin, A.S. Egorov, D.E. Gremyachkin, K.V. Mitrofanov
References

Gremyachkin et al, INDC(NDS)-0882 (2023)
Dimitriou et al, Nucl. Data Sheets 173 (2021) 144 (recommended data)
Piksaikin et al, EPJ Nuclear Sci. Technol. 6,54 (2020) (methodology)
Piksaikin et al, INDC(NDS)-0784 (2019) (reference DN data)


231PA

Energy: Above Cd Cutoff
6-Groups
Original Model - J. N. ANOUSSIS, D. C. PERRICOS, N. G. CHRYSOCHOIDES, and C. A. MITSONIAS, Relative Abundances for Six Delayed Neutron Groups from Reactor Neutron-Induced Fission of 231Pa,” Radiochimica Acta, 20, 118 (1973).

#Half-life [s]Relative abundance a(i)
157.0 ± 0.0000.104 ± 0.001
224.6 ± 0.0000.155 ± 0.003
315.4 ± 0.0000.178 ± 0.005
46.10 ± 0.0000.053 ± 0.017
54.10 ± 0.0000.251 ± 0.026
61.90 ± 0.0000.259 ± 0.027

Average Half-life : 14.33 ± 0.19 s

Correlation matrix
a1T1a2T2a3T3a4T4a5T5a6T6
a1
1
T1
01
a2
001
T2
0001
a3
00-0.8301
T3
000001
a4
000.150-0.2801
T4
00000001
a5
000.470-0.540-0.3901
T5
0000000001
a6
00-0.1200.3200.080-0.7501
T6
000000000001

6-Groups
Expanded Model using a fixed set of Half-lives
G. D. Spriggs, J. M. Campbell and V. M. Piksaikin, An 8-Group Neutron Model Based on a Consistent Set of Half-Lives, Los Alamos National Laboratory report LA-UR-98-1619, Rev. 3, (October 6, 1999).

#Half-life [s]Relative abundance a(i)
155.6 0.115 ± 0.001
224.5 0.099 ± 0.002
316.3 0.228 ± 0.006
45.21 0.181 ± 0.026
52.37 0.353 ± 0.030
61.04 0.024 ± 0.010

Average Half-life : 14.33 ± 0.19 s

Correlation matrix
a1T1a2T2a3T3a4T4a5T5a6T6
a1
1
T1
01
a2
001
T2
0001
a3
00-0.8501
T3
000001
a4
000.540-0.7401
T4
00000001
a5
00-0.0500.310-0.7701
T5
0000000001
a6
0000-0.0100.060-0.1801
T6
000000000001

Energy: 14.8 MeV
4-Groups
Original Model - M. G. BROWN, S. J. LYLE, and E. B. M. MARTIN, Delayed Neutron Yields from 14.8 MeV Neutron Induced Fission of 238U, 232Th, and 231Pa,” Radiochimica Acta, 15, No. 3, 109 (1971).

#Half-life [s]Relative abundance a(i)
153.4 ± 0.0000.136 ± 0.014
219.2 ± 0.0000.249 ± 0.025
35.50 ± 0.0000.299 ± 0.030
42.00 ± 0.0000.316 ± 0.032

Average Half-life : 14.33 ± 0.91 s

Correlation matrix
a1T1a2T2a3T3a4T4
a1
1
T1
01
a2
00.421
T2
00.74-0.181
a3
00.450.150.461
T3
00.31-0.580.66-0.211
a4
00.42-0.190.54-0.410.821
T4
00.05-0.010.06-0.650.310.461

6-Groups
Expanded Model using a fixed set of Half-lives
G. D. Spriggs, J. M. Campbell and V. M. Piksaikin, An 8-Group Neutron Model Based on a Consistent Set of Half-Lives, Los Alamos National Laboratory report LA-UR-98-1619, Rev. 3, (October 6, 1999).

#Half-life [s]Relative abundance a(i)
155.6 0.126 ± 0.013
224.5 0.068 ± 0.016
316.3 0.232 ± 0.021
45.21 0.205 ± 0.028
52.37 0.341 ± 0.031
61.04 0.028 ± 0.012

Average Half-life : 14.37 ± 0.91 s

Correlation matrix
a1T1a2T2a3T3a4T4a5T5a6T6
a1
1
T1
01
a2
001
T2
0001
a3
00-0.8701
T3
000001
a4
000.570-0.7601
T4
00000001
a5
00-0.1100.360-0.7801
T5
0000000001
a6
000.010-0.0100.070-0.201
T6
000000000001


232TH
Energy: Fast Spectrum
6-Groups
Original Model - G. R. KEEPIN, T. F. WIMETT, and R. K. ZEIGLER, Delayed Neutrons from Fissionable Isotopes of Uranium, Plutonium, and Thorium,” Physical Review, 107, 4, 1044 (Aug. 15, 1957).

#Half-life [s]Relative abundance a(i)
156.0 ± 0.0950.034 ± 0.002
220.8 ± 0.6600.150 ± 0.005
35.74 ± 0.2400.155 ± 0.021
42.16 ± 0.0800.446 ± 0.015
50.571 ± 0.0420.172 ± 0.013
60.211 ± 0.0190.043 ± 0.006

Average Half-life : 6.98 ± 0.23 s

Correlation matrix
a1T1a2T2a3T3a4T4a5T5a6T6
a1
1
T1
01
a2
00.81
T2
00.620.231
a3
00.320.30.31
T3
00.32-0.140.71-0.311
a4
00.740.490.74-0.020.681
T4
00.070.080.05-0.640.230.051
a5
00.250.230.2-0.040.1-0.010.481
T5
00.040.030.03-0.030.02-0.220.250.11
a6
00.030.030.0300.010.010.04-0.050.041
T6
00.030.030.0200.010.010.05-0.040.01-0.011

8-Groups
Expanded Model using a fixed set of Half-lives
G. D. Spriggs, J. M. Campbell and V. M. Piksaikin, An 8-Group Neutron Model Based on a Consistent Set of Half-Lives, Los Alamos National Laboratory report LA-UR-98-1619, Rev. 3, (October 6, 1999).

#Half-life [s]Relative abundance a(i)
155.6 0.033 ± 0.002
224.5 0.073 ± 0.005
316.3 0.093 ± 0.002
45.21 0.136 ± 0.024
52.37 0.381 ± 0.008
61.04 0.140 ± 0.008
70.424 0.114 ± 0.013
80.195 0.028 ± 0.001

Average Half-life : 6.98 ± 0.23 s

Correlation matrix
a1T1a2T2a3T3a4T4a5T5a6T6a7T7a8T8
a1
1
T1
01
a2
001
T2
0001
a3
00-0.7401
T3
000001
a4
000.510-0.701
T4
00000001
a5
000.2200.180-0.5901
T5
0000000001
a6
000.090-0.0800.310-0.5701
T6
000000000001
a7
000.070-0.0500.110-0.060-0.2801
T7
00000000000001
a8
000.010-0.0100.01000-0.030-0.0401
T8
0000000000000001

Energy: 14.23 MeV
6-Groups
Original Model - V.A. Roshchenko, V.M.Piksaikin et al., Temporary characteristics of delayed neutrons and partial cross sections of emissive fission in fission of 232Th by neutrons in the energy range from 3.2-17.9 MeV, Nuclear Physics, 2010, vol.73, No.6, pp.947-955. (in russian)

#Half-life [s]Relative abundance a(i)
156.279 ± 0.4110.039 ± 0.001
221.252 ± 0.1970.149 ± 0.003
35.454 ± 0.0820.161 ± 0.003
42.265 ± 0.0300.482 ± 0.006
50.578 ± 0.0120.130 ± 0.003
60.214 ± 0.0050.038 ± 0.001

Average Half-life : 7.41 ± 0.09 s

Correlation matrix
a1T1a2T2a3T3a4T4a5T5a6T6
a1
1
T1
01
a2
00.661
T2
00.19-0.071
a3
00.190.080.321
T3
00.11-0.30.49-0.081
a4
00.560.490.52-0.030.381
T4
00.150.130.26-0.29-0.090.031
a5
00.070.060.070.010.03-0.050.141
T5
00.050.040.0400.03-0.070.0601
a6
00.010.010.010000.02-0.0101
T6
00.010.010.0100-0.010.020001

8-Groups
Expanded Model using a fixed set of Half-lives
G. D. Spriggs, J. M. Campbell and V. M. Piksaikin, An 8-Group Neutron Model Based on a Consistent Set of Half-Lives, Los Alamos National Laboratory report LA-UR-98-1619, Rev. 3, (October 6, 1999).

#Half-life [s]Relative abundance a(i)
155.6 0.039 ± 0.001
224.5 0.078 ± 0.002
316.3 0.086 ± 0.001
45.21 0.136 ± 0.003
52.37 0.461 ± 0.003
61.04 0.094 ± 0.003
70.424 0.079 ± 0.004
80.195 0.028 ± 0.001

Average Half-life : 7.44 ± 0.08 s

Correlation matrix
a1T1a2T2a3T3a4T4a5T5a6T6a7T7a8T8
a1
1
T1
01
a2
001
T2
0001
a3
00-0.7801
T3
000001
a4
000.480-0.701
T4
00000001
a5
000.2800.120-0.5701
T5
0000000001
a6
000.040-0.0600.250-0.4901
T6
000000000001
a7
000.040-0.0400.110-0.120-0.1501
T7
00000000000001
a8
000.010-0.0100.010-0.010-0.020-0.0301
T8
0000000000000001


232U
Energy: Thermal Spectrum
5-Groups
Original Model - R. W. WALDO, R. A. KARAM, R. A. MEYER, Delayed Neutron Yields: Time Dependent Measurements and a Predictive Model,” Physical Review C, 23, No. 3, 1113 (March 1981).

#Half-life [s]Relative abundance a(i)
154.3 ± 0.1700.120 ± 0.009
219.8 ± 0.1600.300 ± 0.023
34.82 ± 0.2000.306 ± 0.032
41.75 ± 0.2000.258 ± 0.027
50.513 ± 0.1500.016 ± 0.089

Average Half-life : 14.37 ± 0.70 s

Correlation matrix
a1T1a2T2a3T3a4T4a5T5
a1
1
T1
01
a2
00.771
T2
00.750.291
a3
00.490.380.481
T3
00.29-0.240.63-0.231
a4
00.380.090.49-0.410.781
T4
00.010.03-0.01-0.620.220.361
a5
00.010.010.01-0.010.01-0.030.051
T5
00.0100.0100.01-0.020.0101

7-Groups
Expanded Model using a fixed set of Half-lives
G. D. Spriggs, J. M. Campbell and V. M. Piksaikin, An 8-Group Neutron Model Based on a Consistent Set of Half-Lives, Los Alamos National Laboratory report LA-UR-98-1619, Rev. 3, (October 6, 1999).

#Half-life [s]Relative abundance a(i)
155.6 0.110 ± 0.009
224.5 0.144 ± 0.015
316.3 0.178 ± 0.019
45.21 0.218 ± 0.033
52.37 0.270 ± 0.005
61.04 0.076 ± 0.048
70.424 0.005 ± 0.080

Average Half-life : 14.38 ± 0.71 s

Correlation matrix
a1T1a2T2a3T3a4T4a5T5a6T6a7T7
a1
1
T1
01
a2
001
T2
0001
a3
00-0.8601
T3
000001
a4
000.570-0.7501
T4
00000001
a5
00-0.0800.30-0.7401
T5
0000000001
a6
000.020-0.0300.150-0.4601
T6
000000000001
a7
0000000.010-0.010-0.0101
T7
00000000000001


233U
Energy: Thermal Spectrum 6-groups
6-Groups
Original Model - V. M. Piksaikin, L. E. Kazakov et al.,RELATIVE YIELD AND PERIOD OF INDIVIDUAL GROUPS OF DELAYED NEUTRONS IN 233U, 235U AND 239Pu FISSION BY EPITHERMAL NEUTRONS, Atomic Energy, Vol. 92, No. 2, pp 135-142, 2002. (in English)

#Half-life [s]Relative abundance a(i)
154.64 ± 0.190.085 ± 0.001
220.77 ± 0.130.291 ± 0.004
35.25 ± 0.050.254 ± 0.004
42.14 ± 0.030.285 ± 0.003
50.611 ± 0.0130.051 ± 0.001
60.276 ± 0.0060.034 ± 0.001

Average Half-life : 12.67 ± 0.11 s

Correlation matrix
a1T1a2T2a3T3a4T4a5T5a6T6
a1
1
T1
01
a2
00.851
T2
00.650.351
a3
00.50.390.521
T3
00.21-0.180.62-0.11
a4
00.510.330.56-0.220.651
T4
00.040.11-0.02-0.5-0.050.161
a5
00.050.040.05-0.010.03-0.050.121
T5
00.030.020.0400.04-0.050.0501
a6
00.020.020.0100.01-0.010.05-0.0101
T6
00.020.010.0200.01-0.020.05-0.01001

8-Groups
Expanded Model using a fixed set of Half-lives
V. M. Piksaikin, L. E. Kazakov et al.,RELATIVE YIELD AND PERIOD OF INDIVIDUAL GROUPS OF DELAYED NEUTRONS IN 233U, 235U AND 239Pu FISSION BY EPITHERMAL NEUTRONS, Atomic Energy, Vol. 92, No. 2, 2002. (in English) V.M. Piksaikin et al., Relative abundances and periods of delayed neutrons from fission of U-233, U235 and Pu-239 by epithermal neutrons, Atomic energy, 2002, N0.2, pp.135-142. (in Russian)
V.M. Piksaikin, A.S. Egorov, K.V. Mitrofanov. THE ABSOLUTE TOTAL DELAYED NEUTRON YIELDS, RELATIVE ABUNDANCES AND HALF-LIVES OF DELAYED NEUTRON GROUPS FROM NEUTRON INDUCED FISSION OF 232Th, 233U, 236U, 239Pu AND 241Am. INDC(NDS) - 0646, 2013

#Half-life [s]Relative abundance a(i)
155.6 0.078 ± 0.003
224.5 0.164 ± 0.006
316.3 0.15 ± 0.005
45.21 0.209 ± 0.008
52.37 0.287 ± 0.009
61.04 0.046 ± 0.002
70.424 0.048 ± 0.002
80.195 0.0173 ± 0.0009

Average Half-life : 12.64 ± 0.24 s

Correlation matrix
a1T1a2T2a3T3a4T4a5T5a6T6a7T7a8T8
a1
1
T1
01
a2
00.481
T2
00.570.081
a3
00.4-0.230.771
T3
0-0.03-0.63-0.24-0.161
a4
00.380.10.240.090.21
T4
00.14-0.20.11-0.250.54-0.11
a5
00.560.220.460.20.08-0.30.591
T5
0-0.03-0.03-0.100.06-0.57-0.040.171
a6
00.060.030.050.030.01-0.020.03-0.070.161
T6
00.0100.0200.01-0.010.06-0.05-0.050.011
a7
00.050.020.030.020-0.010-0.030.13-0.020.031
T7
00.030.010.020.010-0.010.01-0.040.09-0.01001
a8
00.0100.01000000.0200.01-0.0101
T8
00.0100.010000-0.010.0300.01-0.01001

Energy: 0.59MeV
6-Groups
Original Model - Piksaikin V.M., Roshchenko V.A., Isaev S.G., et al., Cumulative Yields and Average Half-Life of Delayed Neutron Precursors From Neutron Induced Fission of U-233 Proc. of XII-th International Seminar on Interaction of Neutrons with Nuclei Neutron Spectroscopy, Nuclear Structure, Related Topics, Dubna, Russia, 24-28 May, 2004, pp.342-353.

#Half-life [s]Relative abundance a(i)
154.6 ± 0.3850.086 ± 0.002
220.9 ± 0.2280.275 ± 0.006
35.66 ± 0.1040.233 ± 0.006
42.31 ± 0.0580.310 ± 0.007
50.539 ± 0.0190.074 ± 0.003
60.221 ± 0.0080.023 ± 0.001

Average Half-life : 12.50 ± 0.19 s

Correlation matrix
a1T1a2T2a3T3a4T4a5T5a6T6
a1
1
T1
01
a2
00.81
T2
00.380.131
a3
00.390.260.521
T3
00.06-0.320.54-0.031
a4
00.490.390.5-0.110.451
T4
00.140.150.16-0.3-0.050.091
a5
00.050.040.040.010.03-0.040.091
T5
00.040.030.0400.04-0.040.0501
a6
00.010.0100000.01001
T6
00.010.010.0100-0.010.020001

8-Groups
Expanded Model using a fixed set of Half-lives
V.M. Piksaikin, A.S. Egorov, K.V. Mitrofanov. THE ABSOLUTE TOTAL DELAYED NEUTRON YIELDS, RELATIVE ABUNDANCES AND HALF-LIVES OF DELAYED NEUTRON GROUPS FROM NEUTRON INDUCED FISSION OF 232Th, 233U, 236U, 239Pu AND 241Am. INDC(NDS) - 0646, 2013

#Half-life [s]Relative abundance a(i)
155.6 0.079 ± 0.003
224.5 0.159 ± 0.006
316.3 0.143 ± 0.005
45.21 0.219 ± 0.008
52.37 0.291 ± 0.009
61.04 0.026 ± 0.001
70.424 0.073 ± 0.004
80.195 0.009 ± 0.001

Average Half-life : 12.51 ± 0.24 s

Correlation matrix
a1T1a2T2a3T3a4T4a5T5a6T6a7T7a8T8
a1
1
T1
01
a2
001
T2
0001
a3
00-0.8401
T3
000001
a4
000.580-0.7601
T4
00000001
a5
00-0.0300.30-0.7301
T5
0000000001
a6
000.010-0.0100.060-0.1801
T6
000000000001
a7
000.030-0.0400.120-0.250-0.0401
T7
00000000000001
a8
0000000.010-0.01000-0.0101
T8
0000000000000001

Energy: 14.7 MeV
6-Groups
Original Model - L. V. EAST, R. H. AUGUSTON, and H. O. MENLOVE, Delayed Neutron Abundances and Half-Lives for 14.7-MeV Fission,” excerpt from Los Alamos National Laboratory Program Status Report LA-4605-MS (September-December, 1970), p. 15.
L. V. EAST, R. H. AUGUSTSON, H. O. MENLOVE, and C. F. MASTERS, Delayed- Neutron Abundances and Half-Lives from 14.7-MeV Fission,” Trans Amer. Nucl. Soc., 13, 760 (November, 1970).

#Half-life [s]Relative abundance a(i)
155.6 ± 0.4000.095 ± 0.002
219.3 ± 0.2000.208 ± 0.002
35.04 ± 0.2000.242 ± 0.016
42.18 ± 0.0800.327 ± 0.014
50.570 ± 0.0300.087 ± 0.004
60.221 ± 0.0000.041 ± 0.003

Average Half-life : 11.29 ± 0.17 s

Correlation matrix
a1T1a2T2a3T3a4T4a5T5a6T6
a1
1
T1
01
a2
00.561
T2
00.73-0.031
a3
00.360.170.361
T3
00.32-0.450.66-0.251
a4
00.480.020.56-0.430.761
T4
0-0.020.11-0.07-0.660.060.241
a5
00.070.050.06-0.050.02-0.110.281
T5
00.0300.04-0.020.05-0.120.110.021
a6
00.020.020.01-0.010-0.010.06-0.030.021
T6
00.020.010.01-0.010-0.020.06-0.030-0.011

8-Groups
Expanded Model using a fixed set of Half-lives
G. D. Spriggs, J. M. Campbell and V. M. Piksaikin, An 8-Group Neutron Model Based on a Consistent Set of Half-Lives, Los Alamos National Laboratory report LA-UR-98-1619, Rev. 3, (October 6, 1999).

#Half-life [s]Relative abundance a(i)
155.6 0.093 ± 0.002
224.5 0.078 ± 0.002
316.3 0.140 ± 0.003
45.21 0.204 ± 0.018
52.37 0.330 ± 0.008
61.04 0.058 ± 0.009
70.424 0.072 ± 0.001
80.195 0.026 ± 0.002

Average Half-life : 11.28 ± 0.17 s

Correlation matrix
a1T1a2T2a3T3a4T4a5T5a6T6a7T7a8T8
a1
1
T1
01
a2
001
T2
0001
a3
00-0.8501
T3
000001
a4
000.530-0.7401
T4
00000001
a5
00-0.0400.310-0.7601
T5
0000000001
a6
000.020-0.0400.150-0.3801
T6
000000000001
a7
000.030-0.0400.120-0.210-0.0901
T7
00000000000001
a8
000.010-0.0100.020-0.030-0.020-0.0301
T8
0000000000000001


235U
Energy: Thermal spectrum 6-groups
6-Groups
Original Model - V. M. Piksaikin, L. E. Kazakov et al.,RELATIVE YIELD AND PERIOD OF INDIVIDUAL GROUPS OF DELAYED NEUTRONS IN 233U, 235U AND 239Pu FISSION BY EPITHERMAL NEUTRONS, Atomic Energy, Vol. 92, No. 2, p. 147, 2002. (in English)
V.M. Piksaikin, L.E. Kazakov, S.G. Isaev, M.Z. Tarasko, V.A.Roshchenko, G.D. Spriggs, J.M. Campbell, Energy Dependence of Relative Abundances and Periods of Delayed Neutrons from Neutron Induced Fission of U-235, U-238, Pu-239 in 6- and 8-group Model Representation, Progress in Nuclear Energy, 2002, v.41, No.1-4, pp.203-222.

#Half-life [s]Relative abundance a(i)
153.9 ± 0.2840.038 ± 0.001
222.3 ± 0.1320.211 ± 0.004
36.40 ± 0.0830.197 ± 0.004
42.26 ± 0.0330.396 ± 0.005
50.494 ± 0.0170.132 ± 0.004
60.179 ± 0.0060.026 ± 0.001

Average Half-life : 8.98 ± 0.11 s

Correlation matrix
a1T1a2T2a3T3a4T4a5T5a6T6
a1
1
T1
01
a2
00.861
T2
00.430.241
a3
00.370.410.261
T3
00.16-0.140.68-0.381
a4
00.670.550.68-0.070.651
T4
00.130.10.18-0.590.360.241
a5
00.130.130.11-0.020.06-0.020.31
T5
00.090.080.080.010.05-0.10.22-0.011
a6
00.020.010.020.0100.010.01-0.0101
T6
00.010.010.010000.03-0.02001

8-Groups
Expanded Model using a fixed set of Half-lives
Expansion method: V.M. Piksaikin, L.E. Kazakov, S.G. Isaev, M.Z. Tarasko, V.A.Roshchenko, G.D. Spriggs, J.M. Campbell, Energy Dependence of Relative Abundances and Periods of Delayed Neutrons from Neutron Induced Fission of U-235, U-238, Pu-239 in 6- and 8-group Model Representation, Progress in Nuclear Energy, 2002, v.41, No.1-4, pp.203-222.

#Half-life [s]Relative abundance a(i)
155.6 0.034 ± 0.001
224.5 0.153 ± 0.006
316.3 0.086 ± 0.004
45.21 0.212 ± 0.007
52.37 0.298 ± 0.009
61.04 0.105 ± 0.005
70.424 0.073 ± 0.004
80.195 0.039 ± 0.002

Average Half-life : 9.00 ± 0.18 s

Correlation matrix
a1T1a2T2a3T3a4T4a5T5a6T6a7T7a8T8
a1
1
T1
01
a2
001
T2
0001
a3
00-0.7301
T3
000001
a4
000.590-0.7401
T4
00000001
a5
000.1800.210-0.5701
T5
0000000001
a6
000.080-0.0800.250-0.5201
T6
000000000001
a7
000.050-0.0500.10-0.110-0.1501
T7
00000000000001
a8
000.010-0.0100.020-0.020-0.040-0.0401
T8
0000000000000001

Energy: 0.42 MeV
6-Groups
Original Model - D.E. Gremyachkin, K.V. Mitrofanov, A.S. Egorov, V.F. Mitrofanov, V.M. Piksaikin. Verification of the energy dependence of the fission product yields from the GEF code for neutron induced fission of 235U on the basis of delayed neutron temporary data. INDC(NDS)-0882, 2023.

#Half-life [s]Relative abundance a(i)
153.691 ± 0.4660.039 ± 0.001
221.358 ± 0.1640.228 ± 0.005
35.553 ± 0.1460.188 ± 0.006
42.245 ± 0.0450.393 ± 0.011
50.518 ± 0.0180.126 ± 0.004
60.178 ± 0.0060.026 ± 0.001

Average Half-life : 8.96± 0.13 s

Correlation matrix
a1T1a2T2a3T3a4T4a5T5a6T6
a1
1
T1
01
a2
00.791
T2
00.070.031
a3
00.250.260.381
T3
00-0.230.63-0.141
a4
00.540.560.51-0.010.491
T4
00.130.190.12-0.410.020.11
a5
00.070.080.060.010.03-0.040.171
T5
00.060.060.060.010.04-0.070.12-0.011
a6
00000000.01001
T6
00.010.010.010000.02-0.01001

8-Groups
Expanded Model using a fixed set of Half-lives

Expansion method: V.M. Piksaikin, L.E. Kazakov, S.G. Isaev, M.Z. Tarasko, V.A.Roshchenko, G.D. Spriggs, J.M. Campbell, Energy Dependence of Relative Abundances and Periods of Delayed Neutrons from Neutron Induced Fission of U-235, U-238, Pu-239 in 6- and 8-group Model Representation, Progress in Nuclear Energy, 2002, v.41, No.1-4, pp.203-222.
V.M. Piksaikin, A.S. Egorov, D.E. Gremyachkin, K.V. Mitrofanov, V.F. Mitrofanov. Generation of correlation and covariance matrices for the recommended temporal DN parameters in 6- and 8-group models. EPJ Nuclear Sci. Technol. 6, 54 (2020).

#Half-life [s]Relative abundance a(i)
155.6 0.034 ± 0.001
224.5 0.147 ± 0.006
316.3 0.102 ± 0.004
45.21 0.178 ± 0.007
52.37 0.347 ± 0.010
61.04 0.096 ± 0.005
70.424 0.070 ± 0.003
80.195 0.026 ± 0.001

Average Half-life : 9.01 ± 0.17 s

Correlation matrix
a1T1a2T2a3T3a4T4a5T5a6T6a7T7a8T8
a1
1
T1
01
a2
001
T2
0001
a3
00-0.5401
T3
000001
a4
000.380-0.5101
T4
00000001
a5
000.4300.070-0.4701
T5
0000000001
a6
000.0400.0200.070-0.2601
T6
000000000001
a7
000.020000.050-0.090-0.0501
T7
00000000000001
a8
000.010000.010-0.010-0.010-0.0101
T8
0000000000000001

Energy: 0.47 MeV
6-Groups
Original Model - D.E. Gremyachkin, K.V. Mitrofanov, A.S. Egorov, V.F. Mitrofanov, V.M. Piksaikin. Verification of the energy dependence of the fission product yields from the GEF code for neutron induced fission of 235U on the basis of delayed neutron temporary data. INDC(NDS)-0882, 2023.

#Half-life [s]Relative abundance a(i)
154.692 ± 0.3890.038 ± 0.001
221.601 ± 0.1500.228 ± 0.005
35.717 ± 0.1420.194 ± 0.006
42.142 ± 0.0400.389 ± 0.011
50.534 ± 0.0190.124 ± 0.004
60.178 ± 0.0060.026 ± 0.001

Average Half-life : 9.04± 0.13 s

Correlation matrix
a1T1a2T2a3T3a4T4a5T5a6T6
a1
1
T1
01
a2
00.841
T2
00.270.151
a3
00.330.320.391
T3
00.08-0.180.66-0.191
a4
00.620.570.580.010.561
T4
00.140.170.1-0.470.120.131
a5
00.090.10.080.010.04-0.050.21
T5
00.070.070.070.010.05-0.080.14-0.011
a6
000.0100000.01001
T6
00.010.010.010000.02-0.01001

8-Groups
Expanded Model using a fixed set of Half-lives

Expansion method: V.M. Piksaikin, L.E. Kazakov, S.G. Isaev, M.Z. Tarasko, V.A.Roshchenko, G.D. Spriggs, J.M. Campbell, Energy Dependence of Relative Abundances and Periods of Delayed Neutrons from Neutron Induced Fission of U-235, U-238, Pu-239 in 6- and 8-group Model Representation, Progress in Nuclear Energy, 2002, v.41, No.1-4, pp.203-222.
V.M. Piksaikin, A.S. Egorov, D.E. Gremyachkin, K.V. Mitrofanov, V.F. Mitrofanov. Generation of correlation and covariance matrices for the recommended temporal DN parameters in 6- and 8-group models. EPJ Nuclear Sci. Technol. 6, 54 (2020).

#Half-life [s]Relative abundance a(i)
155.6 0.035 ± 0.001
224.5 0.142 ± 0.005
316.3 0.110 ± 0.004
45.21 0.169 ± 0.007
52.37 0.336 ± 0.010
61.04 0.108 ± 0.005
70.424 0.074 ± 0.004
80.195 0.026 ± 0.001

Average Half-life : 9.03 ± 0.17 s

Correlation matrix
a1T1a2T2a3T3a4T4a5T5a6T6a7T7a8T8
a1
1
T1
01
a2
001
T2
0001
a3
00-0.5501
T3
000001
a4
000.380-0.5201
T4
00000001
a5
000.4100.060-0.4701
T5
0000000001
a6
000.0500.0200.080-0.2901
T6
000000000001
a7
000.020000.050-0.080-0.0601
T7
00000000000001
a8
000.010000.010-0.010-0.010-0.0101
T8

Energy: 0.81 MeV
6-Groups
Original Model - Piksaikin, V.M., Kazakov, L.E., Isaev, S.G., Tarasko, M.Z., Roshchenko, V.A., Tertytchnyi, R.G., Springs, G.D., Campbell, J.M., 2002. Energy dependence of relative abundances and periods of delayed neutrons from neutron-induced fission of 235U, 238U, 239Pu in 6- and 8-group model representation. Prog. Nucl. Energy 41 (1-4), 203-222.

#Half-life [s]Relative abundance a(i)
154.9 ± 0.1550.036 ± 0.0004
221.9 ± 0.0810.224 ± 0.002
35.88 ± 0.0500.188 ± 0.003
42.23 ± 0.0200.398 ± 0.003
50.488 ± 0.0080.129 ± 0.002
60.180 ± 0.0030.025 ± 0.0005

Average Half-life : 8.96 ± 0.06 s

Correlation matrix
a1T1a2T2a3T3a4T4a5T5a6T6
a1
1
T1
01
a2
00.821
T2
00.420.161
a3
00.330.270.381
T3
00.18-0.170.68-0.171
a4
00.660.540.64-0.030.591
T4
00.130.160.1-0.480.080.121
a5
00.10.10.0800.03-0.050.221
T5
00.060.050.0600.04-0.090.15-0.011
a6
00.010.010.010000.02-0.0101
T6
00.010.010.010000.02-0.01001

8-Groups
Expanded Model using a fixed set of Half-lives
Expansion method: V.M. Piksaikin, L.E. Kazakov, S.G. Isaev, M.Z. Tarasko, V.A.Roshchenko, G.D. Spriggs, J.M. Campbell, Energy Dependence of Relative Abundances and Periods of Delayed Neutrons from Neutron Induced Fission of U-235, U-238, Pu-239 in 6- and 8-group Model Representation, Progress in Nuclear Energy, 2002, v.41, No.1-4, pp.203-222.

#Half-life [s]Relative abundance a(i)
155.6 0.033 ± 0.001
224.5 0.144 ± 0.006
316.3 0.104 ± 0.004
45.21 0.173 ± 0.007
52.37 0.351 ± 0.011
61.04 0.073 ± 0.004
70.424 0.095 ± 0.005
80.195 0.027 ± 0.001

Average Half-life : 8.91 ± 0.18 s

Correlation matrix
a1T1a2T2a3T3a4T4a5T5a6T6a7T7a8T8
a1
1
T1
01
a2
001
T2
0001
a3
00-0.7101
T3
000001
a4
000.570-0.7401
T4
00000001
a5
000.2500.190-0.5401
T5
0000000001
a6
000.050-0.0500.180-0.401
T6
000000000001
a7
000.060-0.0600.150-0.190-0.1401
T7
00000000000001
a8
000.010-0.0100.020-0.010-0.020-0.0401
T8
0000000000000001

Energy: 0.92 MeV
6-Groups
Original Model - D.E. Gremyachkin, K.V. Mitrofanov, A.S. Egorov, V.F. Mitrofanov, V.M. Piksaikin. Verification of the energy dependence of the fission product yields from the GEF code for neutron induced fission of 235U on the basis of delayed neutron temporary data. INDC(NDS)-0882, 2023.

#Half-life [s]Relative abundance a(i)
153.254 ± 0.4940.040 ± 0.001
221.573 ± 0.1750.221 ± 0.005
35.884 ± 0.1520.199 ± 0.006
42.138 ± 0.0440.384 ± 0.011
50.528 ± 0.0180.129 ± 0.004
60.178 ± 0.0060.027 ± 0.001

Average Half-life : 8.95±0,14

Correlation matrix
a1T1a2T2a3T3a4T4a5T5a6T6
a1
1.00
T1
0.001.00
a2
0.000.771.00
T2
0.00-0.03-0.041.00
a3
0.000.240.270.401.00
T3
0.00-0.03-0.270.64-0.151.00
a4
0.000.500.520.490.020.501.00
T4
0.000.120.170.13-0.420.110.121.00
a5
0.000.070.080.060.010.04-0.050.171.00
T5
0.000.060.060.060.010.05-0.080.12-0.011.00
a6
0.000.000.000.000.000.000.000.010.000.001.00
T6
0.000.010.010.010.000.000.000.02-0.010.000.001.00

8-Groups
Expanded Model using a fixed set of Half-lives

Expansion method: V.M. Piksaikin, L.E. Kazakov, S.G. Isaev, M.Z. Tarasko, V.A.Roshchenko, G.D. Spriggs, J.M. Campbell, Energy Dependence of Relative Abundances and Periods of Delayed Neutrons from Neutron Induced Fission of U-235, U-238, Pu-239 in 6- and 8-group Model Representation, Progress in Nuclear Energy, 2002, v.41, No.1-4, pp.203-222.
V.M. Piksaikin, A.S. Egorov, D.E. Gremyachkin, K.V. Mitrofanov, V.F. Mitrofanov. Generation of correlation and covariance matrices for the recommended temporal DN parameters in 6- and 8-group models. EPJ Nuclear Sci. Technol. 6, 54 (2020).

#Half-life [s]Relative abundance a(i)
155.6 0.034 ± 0.001
224.5 0.147 ± 0.006
316.3 0.099 ± 0.004
45.21 0.189 ± 0.007
52.37 0.310 ± 0.010
61.04 0.119 ± 0.006
70.424 0.075 ± 0.004
80.195 0.026 ± 0.001

Average Half-life : 8,99 ± 0.17 s

Correlation matrix
a1T1a2T2a3T3a4T4a5T5a6T6a7T7a8T8
a1
1
T1
01
a2
001
T2
0001
a3
00-0.5501
T3
000001
a4
000.40-0.5201
T4
00000001
a5
000.3800.070-0.4701
T5
0000000001
a6
000.0700.0200.080-0.301
T6
000000000001
a7
000.030000.050-0.080-0.0701
T7
00000000000001
a8
000.010000.010-0.010-0.010-0.0101
T8
0000000000000001

Energy: 1.92 MeV
6-Groups
Original Model - D.E. Gremyachkin, K.V. Mitrofanov, A.S. Egorov, V.F. Mitrofanov, V.M. Piksaikin. Verification of the energy dependence of the fission product yields from the GEF code for neutron induced fission of 235U on the basis of delayed neutron temporary data. INDC(NDS)-0882, 2023.

#Half-life [s]Relative abundance a(i)
155.018 ± 0.5100.040 ± 0.001
221.569 ± 0.1820.215 ± 0.005
35.966 ± 0.1550.197 ± 0.006
42.200 ± 0.0440.399 ± 0.011
50.535 ± 0.0190.122 ± 0.004
60.176 ± 0.0060.027 ± 0.001

Average Half-life : 8.94±0,14 s

Correlation matrix
a1T1a2T2a3T3a4T4a5T5a6T6
a1
1.00
T1
0.001.00
a2
0.000.771.00
T2
0.000.04-0.031.00
a3
0.000.250.260.401.00
T3
0.000.00-0.270.64-0.141.00
a4
0.000.520.520.510.010.511.00
T4
0.000.120.170.13-0.420.090.121.00
a5
0.000.070.080.060.010.03-0.050.171.00
T5
0.000.060.060.060.010.05-0.070.12-0.011.00
a6
0.000.000.000.000.000.000.000.010.000.001.00
T6
0.000.010.010.010.000.000.000.02-0.010.000.001.00

8-Groups
Expanded Model using a fixed set of Half-lives

Expansion method: V.M. Piksaikin, L.E. Kazakov, S.G. Isaev, M.Z. Tarasko, V.A.Roshchenko, G.D. Spriggs, J.M. Campbell, Energy Dependence of Relative Abundances and Periods of Delayed Neutrons from Neutron Induced Fission of U-235, U-238, Pu-239 in 6- and 8-group Model Representation, Progress in Nuclear Energy, 2002, v.41, No.1-4, pp.203-222.
V.M. Piksaikin, A.S. Egorov, D.E. Gremyachkin, K.V. Mitrofanov, V.F. Mitrofanov. Generation of correlation and covariance matrices for the recommended temporal DN parameters in 6- and 8-group models. EPJ Nuclear Sci. Technol. 6, 54 (2020).

#Half-life [s]Relative abundance a(i)
155.6 0.038 ± 0.001
224.5 0.129 ± 0.005
316.3 0.112 ± 0.004
45.21 0.183 ± 0.007
52.37 0.337 ± 0.010
61.04 0.100 ± 0.005
70.424 0.074 ± 0.004
80.195 0.027 ± 0.001

Average Half-life : 8,96 ± 0.17 s

Correlation matrix
a1T1a2T2a3T3a4T4a5T5a6T6a7T7a8T8
a1
1
T1
01
a2
001
T2
0001
a3
00-0.5801
T3
000001
a4
000.390-0.5301
T4
00000001
a5
000.3700.090-0.501
T5
0000000001
a6
000.0400.0200.070-0.2801
T6
000000000001
a7
000.020000.050-0.090-0.0601
T7
00000000000001
a8
000.010000.010-0.020-0.010-0.0101
T8
0000000000000001

Energy: 2.92 MeV
6-Groups
Original Model - D.E. Gremyachkin, K.V. Mitrofanov, A.S. Egorov, V.F. Mitrofanov, V.M. Piksaikin. Verification of the energy dependence of the fission product yields from the GEF code for neutron induced fission of 235U on the basis of delayed neutron temporary data. INDC(NDS)-0882, 2023.

#Half-life [s]Relative abundance a(i)
154.784 ± 0.4540.040 ± 0.001
221.722 ± 0.1720.210 ± 0.005
35.950 ± 0.1480.199 ± 0.006
42.148 ± 0.0410.400 ± 0.011
50.534 ± 0.0190.124 ± 0.004
60.177 ± 0.0060.027 ± 0.001

Average Half-life : 8.86±0,13 s

Correlation matrix
a1T1a2T2a3T3a4T4a5T5a6T6
a1
1.00
T1
0.001.00
a2
0.0000.8101.000
T2
0.0000.1500.0501.000
a3
0.0000.3000.3000.3901.00
T3
0.0000.040-0.2300.660-0.181.00
a4
0.0000.5700.5400.5600.020.551.00
T4
0.0000.1300.1700.110-0.470.140.141.00
a5
0.000.080.090.070.010.04-0.050.191.00
T5
0.000.070.060.060.010.05-0.080.14-0.011.00
a6
0.000.000.000.000.000.000.000.010.000.001.00
T6
0.000.010.010.010.000.000.000.02-0.010.000.001.00

8-Groups
Expanded Model using a fixed set of Half-lives

Expansion method: V.M. Piksaikin, L.E. Kazakov, S.G. Isaev, M.Z. Tarasko, V.A.Roshchenko, G.D. Spriggs, J.M. Campbell, Energy Dependence of Relative Abundances and Periods of Delayed Neutrons from Neutron Induced Fission of U-235, U-238, Pu-239 in 6- and 8-group Model Representation, Progress in Nuclear Energy, 2002, v.41, No.1-4, pp.203-222.
V.M. Piksaikin, A.S. Egorov, D.E. Gremyachkin, K.V. Mitrofanov, V.F. Mitrofanov. Generation of correlation and covariance matrices for the recommended temporal DN parameters in 6- and 8-group models. EPJ Nuclear Sci. Technol. 6, 54 (2020).

#Half-life [s]Relative abundance a(i)
155.6 0.037 ± 0.001
224.5 0.131 ± 0.005
316.3 0.105 ± 0.004
45.21 0.181 ± 0.007
52.37 0.334 ± 0.010
61.04 0.106 ± 0.005
70.424 0.079 ± 0.004
80.195 0.028 ± 0.001

Average Half-life : 8,85 ± 0.17 s

Correlation matrix
a1T1a2T2a3T3a4T4a5T5a6T6a7T7a8T8
a1
1
T1
01
a2
001
T2
0001
a3
00-0.5701
T3
000001
a4
000.380-0.5201
T4
00000001
a5
000.3800.070-0.501
T5
0000000001
a6
000.0500.0200.080-0.2901
T6
000000000001
a7
000.030000.050-0.090-0.0701
T7
00000000000001
a8
000.010000.010-0.010-0.010-0.0101
T8
0000000000000001

Energy: 4 MeV
6-Groups
Original Model - D.E. Gremyachkin, K.V. Mitrofanov, A.S. Egorov, V.F. Mitrofanov, V.M. Piksaikin. Verification of the energy dependence of the fission product yields from the GEF code for neutron induced fission of 235U on the basis of delayed neutron temporary data. INDC(NDS)-0882, 2023.

#Half-life [s]Relative abundance a(i)
154.920 ± 0.3400.0400 ± 0.0008
221.930 ± 0.1600.210 ± 0.004
35.850 ± 0.1300.204 ± 0.005
42.280 ± 0.0400.392 ± 0.009
50.525 ± 0.0150.127 ± 0.004
60.177 ± 0.0050.027 ± 0.001

Average Half-life : 8.96±0.11 s

Correlation matrix
a1T1a2T2a3T3a4T4a5T5a6T6
a1
1.00
T1
0.001.00
a2
0.000.731.00
T2
0.000.11-0.041.00
a3
0.000.270.220.411.00
T3
0.000.04-0.300.59-0.111.00
a4
0.000.510.480.48-0.020.461.00
T4
0.000.140.180.15-0.350.010.081.00
a5
0.000.070.070.060.010.03-0.050.141.00
T5
0.000.050.050.050.010.04-0.060.09-0.011.00
a6
0.000.000.000.000.000.000.000.010.000.001.00
T6
0.000.010.010.010.000.000.000.010.000.000.001.00

8-Groups
Expanded Model using a fixed set of Half-lives

Expansion method: V.M. Piksaikin, L.E. Kazakov, S.G. Isaev, M.Z. Tarasko, V.A.Roshchenko, G.D. Spriggs, J.M. Campbell, Energy Dependence of Relative Abundances and Periods of Delayed Neutrons from Neutron Induced Fission of U-235, U-238, Pu-239 in 6- and 8-group Model Representation, Progress in Nuclear Energy, 2002, v.41, No.1-4, pp.203-222.
V.M. Piksaikin, A.S. Egorov, D.E. Gremyachkin, K.V. Mitrofanov, V.F. Mitrofanov. Generation of correlation and covariance matrices for the recommended temporal DN parameters in 6- and 8-group models. EPJ Nuclear Sci. Technol. 6, 54 (2020).

#Half-life [s]Relative abundance a(i)
155.6 0.037 ± 0.001
224.5 0.139 ± 0.005
316.3 0.093 ± 0.004
45.21 0.203 ± 0.007
52.37 0.336 ± 0.010
61.04 0.085 ± 0.004
70.424 0.079 ± 0.004
80.195 0.028 ± 0.001

Average Half-life : 8.97 ± 0.17 s

Correlation matrix
a1T1a2T2a3T3a4T4a5T5a6T6a7T7a8T8
a1
1
T1
01
a2
001
T2
0001
a3
00-0.5901
T3
000001
a4
000.370-0.5301
T4
00000001
a5
000.3700.080-0.5201
T5
0000000001
a6
000.0400.0100.060-0.2401
T6
000000000001
a7
000.020000.050-0.110-0.0501
T7
00000000000001
a8
000.010000.010-0.020-0.010-0.0101
T8
0000000000000001

Energy: 4.5 MeV
6-Groups
Original Model - D.E. Gremyachkin, K.V. Mitrofanov, A.S. Egorov, V.F. Mitrofanov, V.M. Piksaikin. Verification of the energy dependence of the fission product yields from the GEF code for neutron induced fission of 235U on the basis of delayed neutron temporary data. INDC(NDS)-0882, 2023.

#Half-life [s]Relative abundance a(i)
155.13 ± 0.370.040 ± 0.001
221.88 ± 0.160.204 ± 0.004
35.60 ± 0.130.201 ± 0.006
42.31 ± 0.040.398 ± 0.011
50.528 ± 0.0180.129 ± 0.004
60.177 ± 0.0060.027 ± 0.001

Average Half-life : 8.79± 0.12 s

Correlation matrix
a1T1a2T2a3T3a4T4a5T5a6T6
a1
1
T1
01
a2
00.861
T2
00.360.221
a3
00.340.340.361
T3
00.13-0.130.67-0.231
a4
00.650.590.63-0.040.611
T4
00.10.140.03-0.540.070.141
a5
00.120.130.0900.03-0.030.271
T5
00.070.060.0600.04-0.080.1601
a6
00.010.010.010000.02-0.0101
T6
00.010.010.010000.02-0.01001

8-Groups
Expanded Model using a fixed set of Half-lives

Expansion method: V.M. Piksaikin, L.E. Kazakov, S.G. Isaev, M.Z. Tarasko, V.A.Roshchenko, G.D. Spriggs, J.M. Campbell, Energy Dependence of Relative Abundances and Periods of Delayed Neutrons from Neutron Induced Fission of U-235, U-238, Pu-239 in 6- and 8-group Model Representation, Progress in Nuclear Energy, 2002, v.41, No.1-4, pp.203-222.
V.M. Piksaikin, A.S. Egorov, D.E. Gremyachkin, K.V. Mitrofanov, V.F. Mitrofanov. Generation of correlation and covariance matrices for the recommended temporal DN parameters in 6- and 8-group models. EPJ Nuclear Sci. Technol. 6, 54 (2020).

#Half-life [s]Relative abundance a(i)
155.6 0.038 ± 0.001
224.5 0.134 ± 0.005
316.3 0.088 ± 0.004
45.21 0.191 ± 0.007
52.37 0.368 ± 0.010
61.04 0.061 ± 0.003
70.424 0.092 ± 0.005
80.195 0.028 ± 0.001

Average Half-life : 8.78 ± 0.16 s

Correlation matrix
a1T1a2T2a3T3a4T4a5T5a6T6a7T7a8T8
a1
1
T1
01
a2
001
T2
0001
a3
00-0.5701
T3
000001
a4
000.340-0.5101
T4
00000001
a5
000.4100.070-0.5101
T5
0000000001
a6
000.0200.0100.050-0.1801
T6
000000000001
a7
000.030000.070-0.130-0.0401
T7
00000000000001
a8
000.010000.010-0.020-0.010-0.0201
T8
0000000000000001

Energy: 5 MeV
6-Groups
Original Model - D.E. Gremyachkin, K.V. Mitrofanov, A.S. Egorov, V.F. Mitrofanov, V.M. Piksaikin. Verification of the energy dependence of the fission product yields from the GEF code for neutron induced fission of 235U on the basis of delayed neutron temporary data. INDC(NDS)-0882, 2023.

#Half-life [s]Relative abundance a(i)
155.60 ± 0.390.040 ± 0.001
221.80 ± 0.180.199 ± 0.004
35.90 ± 0.140.205 ± 0.006
42.20 ± 0.040.398 ± 0.011
50.527 ± 0.0180.130 ± 0.004
60.177 ± 0.0060.027 ± 0.001

Average Half-life : 8.76±0.12 s

Correlation matrix
a1T1a2T2a3T3a4T4a5T5a6T6
a1
1.00
T1
0.001.00
a2
0.000.811.00
T2
0.000.320.101.00
a3
0.000.340.300.401.00
T3
0.000.12-0.220.66-0.191.00
a4
0.000.630.520.610.000.581.00
T4
0.000.120.150.09-0.500.130.141.00
a5
0.000.100.100.090.010.04-0.040.231.00
T5
0.000.060.060.060.010.05-0.080.140.001.00
a6
0.000.010.010.010.000.000.000.01-0.010.001.00
T6
0.000.010.010.010.000.000.000.02-0.010.000.001.00

8-Groups
Expanded Model using a fixed set of Half-lives

Expansion method: V.M. Piksaikin, L.E. Kazakov, S.G. Isaev, M.Z. Tarasko, V.A.Roshchenko, G.D. Spriggs, J.M. Campbell, Energy Dependence of Relative Abundances and Periods of Delayed Neutrons from Neutron Induced Fission of U-235, U-238, Pu-239 in 6- and 8-group Model Representation, Progress in Nuclear Energy, 2002, v.41, No.1-4, pp.203-222.
V.M. Piksaikin, A.S. Egorov, D.E. Gremyachkin, K.V. Mitrofanov, V.F. Mitrofanov. Generation of correlation and covariance matrices for the recommended temporal DN parameters in 6- and 8-group models. EPJ Nuclear Sci. Technol. 6, 54 (2020).

#Half-life [s]Relative abundance a(i)
155.6 0.039 ± 0.002
224.5 0.120 ± 0.005
316.3 0.103 ± 0.004
45.21 0.190 ± 0.007
52.37 0.341 ± 0.010
61.04 0.095 ± 0.005
70.424 0.086 ± 0.004
80.195 0.026 ± 0.001

Average Half-life : 8.73 ± 0.16 s

Correlation matrix
a1T1a2T2a3T3a4T4a5T5a6T6a7T7a8T8
a1
1
T1
01
a2
001
T2
0001
a3
00-0.5901
T3
000001
a4
000.380-0.5301
T4
00000001
a5
000.3600.090-0.5201
T5
0000000001
a6
000.0400.0100.070-0.2701
T6
000000000001
a7
000.030000.060-0.110-0.0701
T7
00000000000001
a8
000.010000.010-0.010-0.010-0.0101
T8
0000000000000001

Energy: 5.5 MeV
6-Groups
Original Model - D.E. Gremyachkin, K.V. Mitrofanov, A.S. Egorov, V.F. Mitrofanov, V.M. Piksaikin. Verification of the energy dependence of the fission product yields from the GEF code for neutron induced fission of 235U on the basis of delayed neutron temporary data. INDC(NDS)-0882, 2023.

#Half-life [s]Relative abundance a(i)
155.452 ± 0.3730.041 ± 0.001
221.560 ± 0.1560.206 ± 0.004
35.635 ± 0.1300.197 ± 0.006
42.328 ± 0.0370.406 ± 0.011
50.532 ± 0.0180.123 ± 0.004
60.176 ± 0.0060.027 ± 0.001

Average Half-life : 8.81±0.11 s

Correlation matrix
a1T1a2T2a3T3a4T4a5T5a6T6
a1
1.00
T1
0.001.00
a2
0.000.861.00
T2
0.000.390.221.00
a3
0.000.350.330.371.00
T3
0.000.15-0.140.67-0.221.00
a4
0.000.670.580.65-0.040.621.00
T4
0.000.100.150.04-0.540.070.141.00
a5
0.000.120.120.090.000.03-0.030.261.00
T5
0.000.070.060.060.000.04-0.080.170.001.00
a6
0.000.010.010.010.000.000.000.02-0.010.001.00
T6
0.000.010.010.010.000.000.000.03-0.010.000.001.00

8-Groups
Expanded Model using a fixed set of Half-lives

Expansion method: V.M. Piksaikin, L.E. Kazakov, S.G. Isaev, M.Z. Tarasko, V.A.Roshchenko, G.D. Spriggs, J.M. Campbell, Energy Dependence of Relative Abundances and Periods of Delayed Neutrons from Neutron Induced Fission of U-235, U-238, Pu-239 in 6- and 8-group Model Representation, Progress in Nuclear Energy, 2002, v.41, No.1-4, pp.203-222.
V.M. Piksaikin, A.S. Egorov, D.E. Gremyachkin, K.V. Mitrofanov, V.F. Mitrofanov. Generation of correlation and covariance matrices for the recommended temporal DN parameters in 6- and 8-group models. EPJ Nuclear Sci. Technol. 6, 54 (2020).

#Half-life [s]Relative abundance a(i)
155.6 0.039 ± 0.002
224.5 0.124 ± 0.005
316.3 0.101 ± 0.004
45.21 0.185 ± 0.007
52.37 0.380 ± 0.010
61.04 0.054 ± 0.003
70.424 0.091 ± 0.004
80.195 0.026 ± 0.001

Average Half-life : 8.82 ±0.16 s

Correlation matrix
a1T1a2T2a3T3a4T4a5T5a6T6a7T7a8T8
a1
1
T1
01
a2
001
T2
0001
a3
00-0.5901
T3
000001
a4
000.360-0.5301
T4
00000001
a5
000.400.090-0.5201
T5
0000000001
a6
000.0200.0100.050-0.1601
T6
000000000001
a7
000.020000.070-0.140-0.0401
T7
00000000000001
a8
0000000.010-0.020-0.010-0.0201
T8
0000000000000001

Energy: 6 MeV
6-Groups
Original Model - D.E. Gremyachkin, K.V. Mitrofanov, A.S. Egorov, V.F. Mitrofanov, V.M. Piksaikin. Verification of the energy dependence of the fission product yields from the GEF code for neutron induced fission of 235U on the basis of delayed neutron temporary data. INDC(NDS)-0882, 2023.

#Half-life [s]Relative abundance a(i)
155.693 ± 0.3480.040 ± 0.001
221.872 ± 0.1640.199 ± 0.004
35.877 ± 0.1250.203 ± 0.005
42.207 ± 0.0370.402 ± 0.009
50.526 ± 0.0150.129 ± 0.004
60.177 ± 0.0050.027 ± 0.001

Average Half-life : 8.76±0.11 s

Correlation matrix
a1T1a2T2a3T3a4T4a5T5a6T6
a1
1
T1
01
a2
00.761
T2
00.18-0.021
a3
00.290.230.411
T3
00.07-0.290.62-0.131
a4
00.560.490.5300.511
T4
00.130.170.13-0.410.060.11
a5
00.080.080.070.010.04-0.050.171
T5
00.060.050.050.010.04-0.070.1-0.011
a6
00000000.01001
T6
00.010.010.010000.010001

8-Groups
Expanded Model using a fixed set of Half-lives

Expansion method: V.M. Piksaikin, L.E. Kazakov, S.G. Isaev, M.Z. Tarasko, V.A.Roshchenko, G.D. Spriggs, J.M. Campbell, Energy Dependence of Relative Abundances and Periods of Delayed Neutrons from Neutron Induced Fission of U-235, U-238, Pu-239 in 6- and 8-group Model Representation, Progress in Nuclear Energy, 2002, v.41, No.1-4, pp.203-222.
V.M. Piksaikin, A.S. Egorov, D.E. Gremyachkin, K.V. Mitrofanov, V.F. Mitrofanov. Generation of correlation and covariance matrices for the recommended temporal DN parameters in 6- and 8-group models. EPJ Nuclear Sci. Technol. 6, 54 (2020).

#Half-life [s]Relative abundance a(i)
155.6 0.040 ± 0.002
224.5 0.121 ± 0.005
316.3 0.102 ± 0.004
45.21 0.183 ± 0.007
52.37 0.351 ± 0.010
61.04 0.089 ± 0.004
70.424 0.089 ± 0.004
80.195 0.024 ± 0.001

Average Half-life : 8.79 ±0.16 s

Correlation matrix
a1T1a2T2a3T3a4T4a5T5a6T6a7T7a8T8
a1
1
T1
01
a2
001
T2
0001
a3
00-0.601
T3
000001
a4
000.360-0.5301
T4
00000001
a5
000.3700.080-0.5301
T5
0000000001
a6
000.0300.0100.070-0.2501
T6
000000000001
a7
000.030000.060-0.120-0.0601
T7
00000000000001
a8
0000000.010-0.010-0.010-0.0101
T8
0000000000000001

Energy: 6.5 MeV
6-Groups
Original Model - D.E. Gremyachkin, K.V. Mitrofanov, A.S. Egorov, V.F. Mitrofanov, V.M. Piksaikin. Verification of the energy dependence of the fission product yields from the GEF code for neutron induced fission of 235U on the basis of delayed neutron temporary data. INDC(NDS)-0882, 2023.

#Half-life [s]Relative abundance a(i)
155.679 ± 0.3990.041 ± 0.001
222.195 ± 0.1780.211 ± 0.005
35.797 ± 0.1450.201 ± 0.006
42.383 ± 0.0460.393 ± 0.011
50.514 ± 0.0180.126 ± 0.004
60.177 ± 0.0060.027 ± 0.001

Average Half-life : 9.12±0.13 s

Correlation matrix
a1T1a2T2a3T3a4T4a5T5a6T6
a1
1
T1
01
a2
00.81
T2
00.220.071
a3
00.310.280.391
T3
00.06-0.230.64-0.151
a4
00.590.540.55-0.030.531
T4
00.120.170.08-0.4400.111
a5
00.090.090.080.010.03-0.040.191
T5
00.060.060.0600.04-0.070.13-0.011
a6
00.010.010.010000.01-0.0101
T6
00.010.010.010000.02-0.01001

8-Groups
Expanded Model using a fixed set of Half-lives

Expansion method: V.M. Piksaikin, L.E. Kazakov, S.G. Isaev, M.Z. Tarasko, V.A.Roshchenko, G.D. Spriggs, J.M. Campbell, Energy Dependence of Relative Abundances and Periods of Delayed Neutrons from Neutron Induced Fission of U-235, U-238, Pu-239 in 6- and 8-group Model Representation, Progress in Nuclear Energy, 2002, v.41, No.1-4, pp.203-222.
V.M. Piksaikin, A.S. Egorov, D.E. Gremyachkin, K.V. Mitrofanov, V.F. Mitrofanov. Generation of correlation and covariance matrices for the recommended temporal DN parameters in 6- and 8-group models. EPJ Nuclear Sci. Technol. 6, 54 (2020).

#Half-life [s]Relative abundance a(i)
155.6 0.040 ± 0.001
224.5 0.143 ± 0.005
316.3 0.087 ± 0.004
45.21 0.211 ± 0.008
52.37 0.342 ± 0.010
61.04 0.073 ± 0.004
70.424 0.080 ± 0.004
80.195 0.024 ± 0.001

Average Half-life : 9.19 ±0.17 s

Correlation matrix
a1T1a2T2a3T3a4T4a5T5a6T6a7T7a8T8
a1
1
T1
01
a2
001
T2
0001
a3
00-0.5801
T3
000001
a4
000.360-0.5201
T4
00000001
a5
000.3700.080-0.5301
T5
0000000001
a6
000.0300.0100.060-0.2101
T6
000000000001
a7
000.020000.060-0.110-0.0501
T7
00000000000001
a8
0000000.010-0.020-0.010-0.0101
T8
0000000000000001

Energy: 7 MeV
6-Groups
Original Model - D.E. Gremyachkin, K.V. Mitrofanov, A.S. Egorov, V.F. Mitrofanov, V.M. Piksaikin. Verification of the energy dependence of the fission product yields from the GEF code for neutron induced fission of 235U on the basis of delayed neutron temporary data. INDC(NDS)-0882, 2023.

#Half-life [s]Relative abundance a(i)
155.803 ± 0.3460.041 ± 0.001
222.566 ± 0.1620.212 ± 0.004
35.983 ± 0.1280.205 ± 0.005
42.359 ± 0.0420.388 ± 0.009
50.518 ± 0.0150.127 ± 0.004
60.177 ± 0.0050.028 ± 0.001

Average Half-life : 9.27±0.12 s

Correlation matrix
a1T1a2T2a3T3a4T4a5T5a6T6
a1
1
T1
01
a2
00.751
T2
00.12-0.021
a3
00.280.240.41
T3
00.04-0.280.61-0.121
a4
00.520.50.5-0.040.481
T4
00.130.170.13-0.37-0.010.081
a5
00.080.080.070.010.04-0.050.151
T5
00.050.050.050.010.04-0.070.1-0.011
a6
0000.010000.01001
T6
00.010.010.010000.010001

8-Groups
Expanded Model using a fixed set of Half-lives

Expansion method: V.M. Piksaikin, L.E. Kazakov, S.G. Isaev, M.Z. Tarasko, V.A.Roshchenko, G.D. Spriggs, J.M. Campbell, Energy Dependence of Relative Abundances and Periods of Delayed Neutrons from Neutron Induced Fission of U-235, U-238, Pu-239 in 6- and 8-group Model Representation, Progress in Nuclear Energy, 2002, v.41, No.1-4, pp.203-222.
V.M. Piksaikin, A.S. Egorov, D.E. Gremyachkin, K.V. Mitrofanov, V.F. Mitrofanov. Generation of correlation and covariance matrices for the recommended temporal DN parameters in 6- and 8-group models. EPJ Nuclear Sci. Technol. 6, 54 (2020).

#Half-life [s]Relative abundance a(i)
155.6 0.040 ± 0.001
224.5 0.148 ± 0.005
316.3 0.085 ± 0.004
45.21 0.207 ± 0.008
52.37 0.344 ± 0.010
61.04 0.047 ± 0.002
70.424 0.102 ± 0.005
80.195 0.026 ± 0.001

Average Half-life : 9,25 ±0.17 s

Correlation matrix
a1T1a2T2a3T3a4T4a5T5a6T6a7T7a8T8
a1
1
T1
01
a2
001
T2
0001
a3
00-0.5801
T3
000001
a4
000.350-0.5101
T4
00000001
a5
000.3900.080-0.5401
T5
0000000001
a6
000.020000.030-0.1301
T6
000000000001
a7
000.030000.070-0.150-0.0301
T7
00000000000001
a8
0000000.010-0.020-0.010-0.0201
T8
0000000000000001

Energy: 7.5 MeV
6-Groups
Original Model - D.E. Gremyachkin, K.V. Mitrofanov, A.S. Egorov, V.F. Mitrofanov, V.M. Piksaikin. Verification of the energy dependence of the fission product yields from the GEF code for neutron induced fission of 235U on the basis of delayed neutron temporary data. INDC(NDS)-0882, 2023.

#Half-life [s]Relative abundance a(i)
156.356 ± 0.4080.041 ± 0.001
222.439 ± 0.1750.222 ± 0.005
36.012 ± 0.1540.195 ± 0.006
42.398 ± 0.0480.389 ± 0.011
50.512 ± 0.0180.125 ± 0.004
60.176 ± 0.0060.028 ± 0.001

Average Half-life : 9.49±0.14 s

Correlation matrix
a1T1a2T2a3T3a4T4a5T5a6T6
a1
1
T1
01
a2
00.81
T2
00.190.061
a3
00.30.270.41
T3
00.05-0.240.63-0.141
a4
00.580.540.54-0.020.511
T4
00.130.170.1-0.430.020.111
a5
00.090.090.070.010.03-0.040.181
T5
00.060.060.060.010.04-0.070.12-0.011
a6
00.010.010.010000.01-0.0101
T6
00.010.010.010000.02-0.01001

8-Groups
Expanded Model using a fixed set of Half-lives

Expansion method: V.M. Piksaikin, L.E. Kazakov, S.G. Isaev, M.Z. Tarasko, V.A.Roshchenko, G.D. Spriggs, J.M. Campbell, Energy Dependence of Relative Abundances and Periods of Delayed Neutrons from Neutron Induced Fission of U-235, U-238, Pu-239 in 6- and 8-group Model Representation, Progress in Nuclear Energy, 2002, v.41, No.1-4, pp.203-222.
V.M. Piksaikin, A.S. Egorov, D.E. Gremyachkin, K.V. Mitrofanov, V.F. Mitrofanov. Generation of correlation and covariance matrices for the recommended temporal DN parameters in 6- and 8-group models. EPJ Nuclear Sci. Technol. 6, 54 (2020).

#Half-life [s]Relative abundance a(i)
155.6 0.042 ± 0.002
224.5 0.148 ± 0.005
316.3 0.095 ± 0.004
45.21 0.200 ± 0.007
52.37 0.347 ± 0.010
61.04 0.044 ± 0.002
70.424 0.097 ± 0.005
80.195 0.027 ± 0.001

Average Half-life : 9,45 ±0.17 s

Correlation matrix
a1T1a2T2a3T3a4T4a5T5a6T6a7T7a8T8
a1
1
T1
01
a2
001
T2
0001
a3
00-0.5901
T3
000001
a4
000.360-0.5301
T4
00000001
a5
000.3800.080-0.5401
T5
0000000001
a6
000.0200.0100.030-0.1301
T6
000000000001
a7
000.030000.070-0.150-0.0301
T7
00000000000001
a8
000.010000.010-0.020-0.010-0.0201
T8
0000000000000001

Energy: 8 MeV
6-Groups
Original Model - D.E. Gremyachkin, K.V. Mitrofanov, A.S. Egorov, V.F. Mitrofanov, V.M. Piksaikin. Verification of the energy dependence of the fission product yields from the GEF code for neutron induced fission of 235U on the basis of delayed neutron temporary data. INDC(NDS)-0882, 2023.

#Half-life [s]Relative abundance a(i)
157.417 ± 0.3740.040 ± 0.001
222.294 ± 0.1610.245 ± 0.005
35.903 ± 0.1370.202 ± 0.005
42.572 ± 0.0520.363 ± 0.009
50.513 ± 0.0150.122 ± 0.003
60.176 ± 0.0050.027 ± 0.001

Average Half-life : 9.97±0.13 s

Correlation matrix
a1T1a2T2a3T3a4T4a5T5a6T6
a1
1
T1
01
a2
00.711
T2
00.06-0.061
a3
00.260.20.421
T3
00.01-0.310.54-0.061
a4
00.460.460.42-0.050.381
T4
00.130.160.19-0.28-0.050.051
a5
00.060.060.050.010.03-0.040.111
T5
00.050.040.040.010.04-0.050.07-0.011
a6
00000000.01001
T6
0000.010000.010001

8-Groups
Expanded Model using a fixed set of Half-lives

Expansion method: V.M. Piksaikin, L.E. Kazakov, S.G. Isaev, M.Z. Tarasko, V.A.Roshchenko, G.D. Spriggs, J.M. Campbell, Energy Dependence of Relative Abundances and Periods of Delayed Neutrons from Neutron Induced Fission of U-235, U-238, Pu-239 in 6- and 8-group Model Representation, Progress in Nuclear Energy, 2002, v.41, No.1-4, pp.203-222.
V.M. Piksaikin, A.S. Egorov, D.E. Gremyachkin, K.V. Mitrofanov, V.F. Mitrofanov. Generation of correlation and covariance matrices for the recommended temporal DN parameters in 6- and 8-group models. EPJ Nuclear Sci. Technol. 6, 54 (2020).

#Half-life [s]Relative abundance a(i)
155.6 0.04247 ± 0.00156
224.5 0.15441 ± 0.00568
316.3 0.11071 ± 0.00429
45.21 0.21813 ± 0.00777
52.37 0.33176 ± 0.01004
61.04 0.01614 ± 8.10E-04
70.424 0.09844 ± 0.00485
80.195 0.02795 ± 0.0014

Average Half-life : 9,94 ±0.18 s

Correlation matrix
a1T1a2T2a3T3a4T4a5T5a6T6a7T7a8T8
a1
1
T1
01
a2
001
T2
0001
a3
00-0.601
T3
00000.001
a4
000.420-0.5601
T4
00000001
a5
000.3200.110-0.5401
T5
0000000001
a6
000.010000.010-0.0501
T6
000000000001
a7
000.030000.070-0.160-0.0101
T7
00000000000001
a8
0000000.010-0.02000-0.0201
T8
0000000000000001

Energy: 14.7 MeV
6-Groups
Original Model - L. V. EAST, R. H. AUGUSTON, and H. O. MENLOVE, Delayed Neutron Abundances and Half-Lives for 14.7-MeV Fission,” excerpt from Los Alamos National Laboratory Program Status Report LA-4605-MS (September-December, 1970), p. 15.
L. V. EAST, R. H. AUGUSTSON, H. O. MENLOVE, and C. F. MASTERS, Delayed- Neutron Abundances and Half-Lives from 14.7-MeV Fission,” Trans Amer. Nucl. Soc., 13, 760 (November, 1970).

#Half-life [s]Relative abundance a(i)
154.6 ± 0.5000.057 ± 0.001
220.2 ± 0.2000.192 ± 0.002
35.36 ± 0.3000.190 ± 0.020
42.38 ± 0.1000.357 ± 0.013
50.770 ± 0.0700.120 ± 0.009
60.240 ± 0.0100.084 ± 0.007

Average Half-life : 8.97 ± 0.15 s

Correlation matrix
a1T1a2T2a3T3a4T4a5T5a6T6
a1
1
T1
01
a2
00.781
T2
00.690.241
a3
00.340.250.341
T3
00.31-0.20.68-0.241
a4
00.630.360.66-0.230.711
T4
0-0.010.09-0.07-0.6300.081
a5
00.160.140.13-0.040.05-0.110.391
T5
00.02-0.010.04-0.020.07-0.180.10.071
a6
00.060.060.0500.0100.1-0.070.081
T6
00.050.050.04-0.010.01-0.020.12-0.060.04-0.031

8-Groups
Expanded Model using a fixed set of Half-lives
G. D. Spriggs, J. M. Campbell and V. M. Piksaikin, An 8-Group Neutron Model Based on a Consistent Set of Half-Lives, Los Alamos National Laboratory report LA-UR-98-1619, Rev. 3, (October 6, 1999).

#Half-life [s]Relative abundance a(i)
155.6 0.052 ± 0.001
224.5 0.099 ± 0.002
316.3 0.107 ± 0.004
45.21 0.185 ± 0.022
52.37 0.346 ± 0.007
61.04 0.079 ± 0.009
70.424 0.087 ± 0.002
80.195 0.045 ± 0.008

Average Half-life : 8.97 ± 0.15 s

Correlation matrix
a1T1a2T2a3T3a4T4a5T5a6T6a7T7a8T8
a1
1
T1
01
a2
001
T2
0001
a3
00-0.8101
T3
000001
a4
000.550-0.7401
T4
00000001
a5
000.100.230-0.6601
T5
0000000001
a6
000.040-0.0600.20-0.4501
T6
000000000001
a7
000.050-0.0500.140-0.190-0.1401
T7
00000000000001
a8
000.010-0.0100.030-0.030-0.030-0.0601
T8
0000000000000001


236U
Energy: 4 MeV 6-groups
6-Groups
Original Model - V.M. Piksaikin, A.S. Egorov, K.V. Mitrofanov. THE ABSOLUTE TOTAL DELAYED NEUTRON YIELDS, RELATIVE ABUNDANCES AND HALF-LIVES OF DELAYED NEUTRON GROUPS FROM NEUTRON INDUCED FISSION OF 232Th, 233U, 236U, 239Pu AND 241Am. INDC(NDS) - 0646, 2013

S.G. Isaev,V.M. Piksaikin,L.E. Kazakov, M.Z. Tarasko, Energy Dependence of Average Half-Life of Delayed Neutron Precursors in Fast Neutron Induced Fission of of U-235 and U-236 Proc. of XIV-th International Workshop on Nuclear Fission Physics, Obninsk, RUSSIA, 12-15 October 1998, c.257-264.

#Half-life [s]Relative abundance a(i)
155.8 ± 0.3750.026 ± 0.001
221.9 ± 0.1420.195 ± 0.004
34.50 ± 0.0530.322 ± 0.006
41.50 ± 0.0360.347 ± 0.008
50.484 ± 0.0170.099 ± 0.003
60.214 ± 0.0080.0128 ± 0.0005

Average Half-life : 7.71 ± 0.11 s

Correlation matrix
a1T1a2T2a3T3a4T4a5T5a6T6
a1
1
T1
01
a2
00.861
T2
00.30.291
a3
00.560.640.41
T3
00.04-0.120.56-0.361
a4
00.50.490.5200.611
T4
00.050.060.03-0.480.270.181
a5
00.080.080.080.020.06-0.070.151
T5
00.060.060.060.020.07-0.070.0401
a6
00.010.0100000.01001
T6
00.010.0100000.010001

8-Groups
Expanded Model using a fixed set of Half-lives
V.M. Piksaikin, A.S. Egorov, K.V. Mitrofanov. THE ABSOLUTE TOTAL DELAYED NEUTRON YIELDS, RELATIVE ABUNDANCES AND HALF-LIVES OF DELAYED NEUTRON GROUPS FROM NEUTRON INDUCED FISSION OF 232Th, 233U, 236U, 239Pu AND 241Am. INDC(NDS) - 0646, 2013

#Half-life [s]Relative abundance a(i)
155.6 0.024 ± 0.001
224.5 0.129 ± 0.005
316.3 0.075 ± 0.003
45.21 0.201 ± 0.007
52.37 0.291 ± 0.009
61.04 0.215 ± 0.009
70.424 0.042 ± 0.003
80.195 0.023 ± 0.001

Average Half-life : 7.72 ± 0.15 s

Correlation matrix
a1T1a2T2a3T3a4T4a5T5a6T6a7T7a8T8
a1
1
T1
01
a2
001
T2
0001
a3
00-0.6701
T3
000001
a4
000.610-0.7201
T4
00000001
a5
000.1900.20-0.5301
T5
0000000001
a6
000.210-0.1600.430-0.6401
T6
000000000001
a7
000.020-0.0200.0300.010-0.1401
T7
00000000000001
a8
000.010000.0100.010-0.040-0.0101
T8
0000000000000001


237NP
Energy: 3.745 MeV
6-Groups
Original Model - V.M. Piksaikin, Yu.F. Balakshev,S.G. Isaev, L.E. Kazakov, G.G. Korolev, V.I. Mil'shin, Measurement of the Energy Dependence of the Parameters of Delayed Neutrons Accompanying Fission of Np-237 by Fast Neutrons, Atomic Energy, 1998, v.85, N. 1, pp.479-486.

#Half-life [s]Relative abundance a(i)
154.7 ± 0.5500.040 ± 0.001
221.8 ± 0.2600.228 ± 0.006
35.74 ± 0.1900.191 ± 0.009
42.26 ± 0.0560.395 ± 0.016
50.719 ± 0.0340.116 ± 0.005
60.199 ± 0.0100.030 ± 0.002

Average Half-life : 9.24 ± 0.17 s

Correlation matrix
a1T1a2T2a3T3a4T4a5T5a6T6
a1
1
T1
01
a2
00.911
T2
00.60.451
a3
00.380.390.331
T3
00.270.020.68-0.311
a4
00.710.620.72-0.080.71
T4
00.040.060.01-0.650.210.151
a5
00.160.170.13-0.030.06-0.060.391
T5
00.030.020.0400.05-0.150.090.071
a6
00.020.020.0100.0100.03-0.020.021
T6
00.020.020.0100.0100.04-0.020.0201

8-Groups
Expanded Model using a fixed set of Half-lives
V.M. Piksaikin, Yu.F. Balakshev,S.G. Isaev, L.E. Kazakov, G.G. Korolev, V.I. Mil'shin, Measurement of the Energy Dependence of the Parameters of Delayed Neutrons Accompanying Fission of Np-237 by Fast Neutrons, Atomic Energy, 1998, v.85, N. 1, pp.479-486.

#Half-life [s]Relative abundance a(i)
155.6 0.036 ± 0.001
224.5 0.155 ± 0.005
316.3 0.092 ± 0.004
45.21 0.189 ± 0.011
52.37 0.337 ± 0.013
61.04 0.129 ± 0.008
70.424 0.038 ± 0.001
80.195 0.024 ± 0.002

Average Half-life : 9.23 ± 0.17 s

Correlation matrix
a1T1a2T2a3T3a4T4a5T5a6T6a7T7a8T8
a1
1
T1
01
a2
001
T2
0001
a3
00-0.7301
T3
000001
a4
000.560-0.7301
T4
00000001
a5
000.1900.190-0.5801
T5
0000000001
a6
000.090-0.0900.310-0.601
T6
000000000001
a7
000.020-0.0200.050-0.040-0.0901
T7
00000000000001
a8
000.010-0.0100.010-0.010-0.030-0.0101
T8
0000000000000001

Energy: 14.23 MeV
6-Groups
Original Model - Gremyachkin D.E., Piksaikin V.M., Egorov A.S., Mitrofanov K.V. Measurements of Temporal Characteristics of Delayed Neutrons from Neutron Induced Fission of the Np-237 in Energy Range from 14.2 to 18 MeV. EPJ Web Conf. 146, 04059 (2017).

#Half-life [s]Relative abundance a(i)
158.20 ± 0.500.045 ± 0.001
220.20 ± 0.200.181 ± 0.003
34.58 ± 0.110.211 ± 0.006
42.12 ± 0.040.451 ± 0.010
50.460 ± 0.5000.100 ± 0.003
60.196 ± 0.5000.013 ± 0.004

Average Half-life : 8.24 ± 0.12 s

Correlation matrix
a1T1a2T2a3T3a4T4a5T5a6T6
a1
1
T1
01
a2
00.671
T2
00.16-0.031
a3
00.230.140.341
T3
00.08-0.270.45-0.051
a4
00.470.450.46-0.10.331
T4
00.150.150.24-0.23-0.170.021
a5
00.040.030.0400.02-0.030.071
T5
00.030.030.0300.03-0.040.0401
a6
00000000001
T6
000000000001

8-Groups
Expanded Model using a fixed set of Half-lives
Expansion method: V.M. Piksaikin, L.E. Kazakov, S.G. Isaev, M.Z. Tarasko, V.A.Roshchenko, G.D. Spriggs, J.M. Campbell, Energy Dependence of Relative Abundances and Periods of Delayed Neutrons from Neutron Induced Fission of U-235, U-238, Pu-239 in 6- and 8-group Model Representation, Progress in Nuclear Energy, 2002, v.41, No.1-4, pp.203-222.
V.M.Piksaikin et al. Generation of correlation and covariance matrices for the recommended Temporal DN parameters in 6- and 8- group models, EPJ Nuclear Sci. Technol., 6, 54,2020

#Half-life [s]Relative abundance a(i)
155.6 0.04961 ± 0.002
224.5 0.05472 ± 0.0022
316.3 0.14229 ± 0.00148
45.21 0.09368 ± 0.00317
52.37 0.53002 ± 0.00339
61.04 0.03844 ± 0.00305
70.424 0.07444 ± 0.00568
80.195 0.0168 ± 0.00167

Average Half-life : 8.24 ± 0.13 s

Correlation matrix
a1T1a2T2a3T3a4T4a5T5a6T6a7T7a8T8
a1
1
T1
01
a2
001
T2
0001
a3
00-0.7401
T3
000001
a4
000.420-0.6501
T4
00000001
a5
000.3100.120-0.5801
T5
0000000001
a6
0000000.10-0.2601
T6
000000000001
a7
000.010-0.0200.120-0.210-0.0701
T7
00000000000001
a8
0000000.010-0.010-0.010-0.0201
T8
0000000000000001


238PU
Energy: Thermal Spectrum
6-Groups
Original Model - R. W. WALDO, R. A. KARAM, R. A. MEYER, Delayed Neutron Yields: Time Dependent Measurements and a Predictive Model,” Physical Review C, 23, No. 3, 1113 (March 1981). R. W. WALDO, and R. A. KARAM, Measured Delayed Neutron Yields,” Trans. Amer. Nucl. Soc., 39, 879 (1981).

#Half-life [s]Relative abundance a(i)
154.9 ± 0.5700.043 ± 0.007
222.9 ± 0.2600.307 ± 0.048
38.15 ± 1.1000.114 ± 0.067
43.52 ± 0.4100.176 ± 0.028
51.95 ± 0.2800.327 ± 0.052
60.513 ± 0.1500.033 ± 0.190

Average Half-life : 11.58 ± 1.31 s

Correlation matrix
a1T1a2T2a3T3a4T4a5T5a6T6
a1
1
T1
01
a2
00.891
T2
00.450.261
a3
00.320.260.441
T3
00.09-0.210.66-0.061
a4
00.310.280.29-0.020.21
T4
00.170.190.19-0.370.05-0.051
a5
00.640.570.560.120.33-0.210.491
T5
00.090.020.15-0.050.32-0.29-0.330.181
a6
00.030.030.0300.02-0.010-0.030.111
T6
00.020.020.0200.0100.02-0.030.0301

7-Groups
Expanded Model using a fixed set of Half-lives
G. D. Spriggs, J. M. Campbell and V. M. Piksaikin, An 8-Group Neutron Model Based on a Consistent Set of Half-Lives, Los Alamos National Laboratory report LA-UR-98-1619, Rev. 3, (October 6, 1999).

#Half-life [s]Relative abundance a(i)
155.6 0.042 ± 0.009
224.5 0.219 ± 0.027
316.3 0.137 ± 0.058
45.21 0.134 ± 0.065
52.37 0.386 ± 0.008
61.04 0.066 ± 0.100
70.424 0.017 ± 0.170

Average Half-life : 11.59 ± 1.31 s

Correlation matrix
a1T1a2T2a3T3a4T4a5T5a6T6a7T7
a1
1
T1
01
a2
001
T2
0001
a3
00-0.6901
T3
000001
a4
000.50-0.7101
T4
00000001
a5
000.300.130-0.5501
T5
0000000001
a6
000.010-0.0200.150-0.401
T6
000000000001
a7
0000-0.0100.030-0.050-0.0201
T7
00000000000001

Energy: Fast Spectrum
5-Groups
Original Model - G. BENEDETTI, A. CESANA, V. SANGIUST, and M. TERRANI, Delayed Neutron Yields from Fission of Uranium-233, Neptunium-237, Plutonium-238, -240, -241, and Americium-241”, Nucl. Sci. Eng., 80, 379 (1982).

#Half-life [s]Relative abundance a(i)
149.5 ± 1.8000.068 ± 0.007
221.9 ± 1.1000.280 ± 0.018
34.95 ± 0.2100.300 ± 0.020
41.87 ± 0.1100.285 ± 0.030
50.578 ± 0.2900.069 ± 0.023

Average Half-life : 11.52 ± 0.64 s

Correlation matrix
a1T1a2T2a3T3a4T4a5T5
a1
1
T1
01
a2
00.941
T2
00.650.61
a3
00.580.610.51
T3
00.160.020.56-0.311
a4
00.550.490.62-0.140.741
T4
0-0.02-0.01-0.03-0.60.270.31
a5
00.080.080.07-0.010.05-0.060.211
T5
00.040.040.0500.06-0.070.050.011

7-Groups
Expanded Model using a fixed set of Half-lives
G. D. Spriggs, J. M. Campbell and V. M. Piksaikin, An 8-Group Neutron Model Based on a Consistent Set of Half-Lives, Los Alamos National Laboratory report LA-UR-98-1619, Rev. 3, (October 6, 1999).

#Half-life [s]Relative abundance a(i)
155.6 0.045 ± 0.008
224.5 0.250 ± 0.018
316.3 0.052 ± 0.001
45.21 0.256 ± 0.014
52.37 0.251 ± 0.035
61.04 0.120 ± 0.012
70.424 0.027 ± 0.016

Average Half-life : 11.52 ± 0.64 s

Correlation matrix
a1T1a2T2a3T3a4T4a5T5a6T6a7T7
a1
1
T1
01
a2
001
T2
0001
a3
00-0.6601
T3
000001
a4
000.410-0.6301
T4
00000001
a5
000.200.150-0.6501
T5
0000000001
a6
000.060-0.0500.260-0.5801
T6
000000000001
a7
000.010-0.0100.030-0.040-0.0701
T7
00000000000001


238U
Energy: 3.75 MeV
6-Groups
Original Model - Piksaikin, V.M., Kazakov, L.E., Isaev, S.G., Tarasko, M.Z., Roshchenko, V.A., Tertytchnyi, R.G., Springs, G.D., Campbell, J.M., 2002. Energy dependence of relative abundances and periods of delayed neutrons from neutron-induced fission of 235U, 238U, 239Pu in 6- and 8-group model representation. Prog. Nucl. Energy 41 (1-4), 203-222.

#Half-life [s]Relative abundance a(i)
152.9 ± 0.1690.013 ± 0.0001
221.8 ± 0.0550.133 ± 0.001
35.12 ± 0.0320.164 ± 0.002
41.97 ± 0.0130.389 ± 0.003
50.496 ± 0.0070.228 ± 0.003
60.173 ± 0.0030.074 ± 0.001

Average Half-life : 5.31 ± 0.03 s

Correlation matrix
a1T1a2T2a3T3a4T4a5T5a6T6
a1
1.00
T1
0.001.00
a2
0.000.771.00
T2
0.000.020.091.00
a3
0.000.260.360.191.00
T3
0.000.06-0.060.65-0.401.00
a4
0.000.530.630.500.000.571.00
T4
0.000.090.130.02-0.580.170.001.00
a5
0.000.240.300.150.020.090.020.421.00
T5
0.000.090.120.08-0.010.06-0.170.280.031.00
a6
0.000.030.040.020.000.010.020.04-0.040.031.00
T6
0.000.040.050.030.000.010.020.06-0.050.02-0.011.00

8-Groups
Expanded Model using a fixed set of Half-lives
Expansion method: V.M. Piksaikin, L.E. Kazakov, S.G. Isaev, M.Z. Tarasko, V.A.Roshchenko, G.D. Spriggs, J.M. Campbell, Energy Dependence of Relative Abundances and Periods of Delayed Neutrons from Neutron Induced Fission of U-235, U-238, Pu-239 in 6- and 8-group Model Representation, Progress in Nuclear Energy, 2002, v.41, No.1-4, pp.203-222.

#Half-life [s]Relative abundance a(i)
155.6 0.010 ± 0.0004
224.5 0.091 ± 0.004
316.3 0.053 ± 0.002
45.21 0.122 ± 0.005
52.37 0.331 ± 0.009
61.04 0.158 ± 0.007
70.424 0.154 ± 0.007
80.195 0.081 ± 0.004

Average Half-life : 5.31 ± 0.11 s

Correlation matrix
a1T1a2T2a3T3a4T4a5T5a6T6a7T7a8T8
a1
1.00
T1
0.001.00
a2
0.000.001.00
T2
0.000.000.001.00
a3
0.000.00-0.430.001.00
T3
0.000.000.000.000.001.00
a4
0.000.000.560.00-0.610.001.00
T4
0.000.000.000.000.000.000.001.00
a5
0.000.000.530.000.180.00-0.270.001.00
T5
0.000.000.000.000.000.000.000.000.001.00
a6
0.000.000.220.00-0.070.000.370.00-0.360.001.00
T6
0.000.000.000.000.000.000.000.000.000.000.001.00
a7
0.000.000.200.00-0.050.000.170.000.090.00-0.320.001.00
T7
0.000.000.000.000.000.000.000.000.000.000.000.000.001.00
a8
0.000.000.050.00-0.010.000.030.000.050.00-0.060.00-0.120.001.00
T8
0.000.000.000.000.000.000.000.000.000.000.000.000.000.000.001.00

Energy: 14.23 MeV
6-Groups
Original Model - V.M. Piksaikin, V.A. Roshchenko, G.G. Korolev, Relative yield of delayed neutrons and half-life of their precursor nuclei from 238U fission by 14.2-17.9 MeV neutrons,” At. Energy 102, 124 (2007).

#Half-life [s]Relative abundance a(i)
153.4 ± 0.4000.022 ± 0.001
220.9 ± 0.2000.144 ± 0.003
34.64 ± 0.0800.188 ± 0.005
41.92 ± 0.0400.412 ± 0.008
50.500 ± 0.0100.180 ± 0.005
60.176 ± 0.0050.054 ± 0.002

Average Half-life : 5.95 ± 0.08 s

Correlation matrix
a1T1a2T2a3T3a4T4a5T5a6T6
a1
1.00
T1
0.001.00
a2
0.000.661.00
T2
0.000.01-0.091.00
a3
0.000.210.200.311.00
T3
0.000.04-0.250.55-0.151.00
a4
0.000.460.510.42-0.040.401.00
T4
0.000.110.180.11-0.35-0.12-0.011.00
a5
0.000.100.110.090.020.05-0.050.181.00
T5
0.000.070.070.060.010.06-0.080.09-0.011.00
a6
0.000.010.010.010.000.000.000.02-0.010.001.00
T6
0.000.010.020.010.000.010.000.03-0.010.000.001.00

8-Groups
Expanded Model using a fixed set of Half-lives
Expansion method: V.M. Piksaikin, L.E. Kazakov, S.G. Isaev, M.Z. Tarasko, V.A.Roshchenko, G.D. Spriggs, J.M. Campbell, Energy Dependence of Relative Abundances and Periods of Delayed Neutrons from Neutron Induced Fission of U-235, U-238, Pu-239 in 6- and 8-group Model Representation, Progress in Nuclear Energy, 2002, v.41, No.1-4, pp.203-222.
V.M.Piksaikin et al. Generation of correlation and covariance matrices for the recommended Temporal DN parameters in 6- and 8- group models, EPJ Nuclear Sci. Technol., 6, 54,2020

#Half-life [s]Relative abundance a(i)
155.6 0.0183 ± 4.70E-04
224.5 0.08475 ± 0.00218
316.3 0.06922 ± 0.00144
45.21 0.11161 ± 0.00292
52.37 0.38513 ± 0.00422
61.04 0.15423 ± 0.0046
70.424 0.11152 ± 0.00655
80.195 0.06524 ± 0.00442

Average Half-life : 5.94 ± 0.07 s

Correlation matrix
a1T1a2T2a3T3a4T4a5T5a6T6a7T7a8T8
a1
1
T1
01
a2
001
T2
0001
a3
00-0.6101
T3
000001
a4
000.490-0.6701
T4
00000001
a5
000.4300.110-0.4401
T5
0000000001
a6
000.140-0.0900.350-0.4901
T6
000000000001
a7
000.090-0.0500.100.010-0.2901
T7
00000000000001
a8
000.030-0.0100.0200.020-0.070-0.0801
T8
0000000000000001


239PU
Energy: Thermal spectrum
6-Groups
Original Model - V. M. Piksaikin, L. E. Kazakov et al.,RELATIVE YIELD AND PERIOD OF INDIVIDUAL GROUPS OF DELAYED NEUTRONS IN 233U, 235U AND 239Pu FISSION BY EPITHERMAL NEUTRONS, Atomic Energy, Vol. 92, No. 2, p. 147, 2002. (in English)
V.M. Piksaikin, L.E. Kazakov, S.G. Isaev, M.Z. Tarasko, V.A.Roshchenko, G.D. Spriggs, J.M. Campbell, Energy Dependence of Relative Abundances and Periods of Delayed Neutrons from Neutron Induced Fission of U-235, U-238, Pu-239 in 6- and 8-group Model Representation, Progress in Nuclear Energy, 2002, v.41, No.1-4, pp.203-222.

#Half-life [s]Relative abundance a(i)
153.198 ± 0.4640.035 ± 0.001
222.609 ± 0.1070.302 ± 0.007
35.59 ± 0.0840.204 ± 0.005
42.17 ± 0.0400.332 ± 0.006
50.621 ± 0.0220.084 ± 0.003
60.256 ± 0.0090.043 ± 0.002

Average Half-life : 10.59 ± 0.17 s

Correlation matrix
a1T1a2T2a3T3a4T4a5T5a6T6
a1
1
T1
01
a2
00.821
T2
0-0.050.191
a3
00.320.460.341
T3
0-0.09-0.110.65-0.271
a4
00.50.640.5-0.030.541
T4
00.060.110-0.530.090.171
a5
00.090.120.060.010.03-0.040.211
T5
00.040.050.050.010.05-0.070.080.011
a6
00.020.030.010000.05-0.020.011
T6
00.030.030.0200.01-0.010.06-0.02001

8-Groups
Expanded Model using a fixed set of Half-lives
V.M. Piksaikin, A.S. Egorov, K.V. Mitrofanov. THE ABSOLUTE TOTAL DELAYED NEUTRON YIELDS, RELATIVE ABUNDANCES AND HALF-LIVES OF DELAYED NEUTRON GROUPS FROM NEUTRON INDUCED FISSION OF 232Th, 233U, 236U, 239Pu AND 241Am. INDC(NDS) - 0646, 2013; V.M. Piksaikin, L.E. Kazakov, S.G. Isaev, M.Z. Tarasko, V.A.Roshchenko, G.D. Spriggs, J.M. Campbell, Energy Dependence of Relative Abundances and Periods of Delayed Neutrons from Neutron Induced Fission of U-235, U-238, Pu-239 in 6- and 8-group Model Representation, Progress in Nuclear Energy, 2002, v.41, No.1-4, pp.203-222;

#Half-life [s]Relative abundance a(i)
155.6 0.029 ± 0.001
224.5 0.240 ± 0.008
316.3 0.083 ± 0.004
45.21 0.188 ± 0.007
52.37 0.289 ± 0.010
61.04 0.089 ± 0.004
70.424 0.059 ± 0.003
80.195 0.023 ± 0.001

Average Half-life : 10.63 ± 0.22

Correlation matrix
a1T1a2T2a3T3a4T4a5T5a6T6a7T7a8T8
a1
1.00
T1
0.001.00
a2
0.000.001.00
T2
0.000.000.001.00
a3
0.000.00-0.670.001.00
T3
0.000.000.000.000.001.00
a4
0.000.000.540.00-0.720.001.00
T4
0.000.000.000.000.000.000.001.00
a5
0.000.000.260.000.170.00-0.550.001.00
T5
0.000.000.000.000.000.000.000.000.001.00
a6
0.000.000.060.00-0.050.000.200.00-0.450.001.00
T6
0.000.000.000.000.000.000.000.000.000.000.001.00
a7
0.000.000.050.00-0.040.000.110.00-0.140.00-0.140.001.00
T7
0.000.000.000.000.000.000.000.000.000.000.000.000.001.00
a8
0.000.000.010.00-0.010.000.010.00-0.010.00-0.020.00-0.020.001.00
T8
0.000.000.000.000.000.000.000.000.000.000.000.000.000.000.001.00

Energy: 0.86MeV
6-Groups
Original Model - V.M. Piksaikin, L.E. Kazakov, S.G. Isaev, M.Z. Tarasko, V.A.Roshchenko, G.D. Spriggs, J.M. Campbell, Energy Dependence of Relative Abundances and Periods of Delayed Neutrons from Neutron Induced Fission of U-235, U-238, Pu-239 in 6- and 8-group Model Representation, Progress in Nuclear Energy, 2002, v.41, No.1-4, pp.203-222;
V.M. Piksaikin et al., Energy dependence of relative abundances and periods of delayed neutrons from fission of Pu-239 in the energy range of primary neutrons from 0.37 to 4.97 MeV, Atomic Energy 92, 2002, No.3, pp.233-239;

#Half-life [s]Relative abundance a(i)
153.81 ± 0.4080.037 ± 0.001
222.19 ± 0.1030.288 ± 0.005
35.25 ± 0.0670.216 ± 0.005
42.06 ± 0.0340.321 ± 0.005
50.547 ± 0.0160.102 ± 0.003
60.217 ± 0.0060.034 ± 0.001

Average Half-life : 10.27 ± 0.13 s

Correlation matrix
a1T1a2T2a3T3a4T4a5T5a6T6
a1
1.00
T1
0.001.00
a2
0.000.881.00
T2
0.000.180.321.00
a3
0.000.170.190.261.00
T3
0.000.01-0.040.63-0.101.00
a4
0.000.570.650.43-0.040.321.00
T4
0.000.080.130.08-0.42-0.22-0.221.00
a5
0.000.430.500.330.020.07-0.070.591.00
T5
0.000.010.000.05-0.020.15-0.380.070.211.00
a6
0.000.080.090.050.010.010.010.07-0.060.141.00
T6
0.000.040.050.030.000.000.000.08-0.040.000.011.00

8-Groups
Expanded Model using a fixed set of Half-lives
V.M. Piksaikin, L.E. Kazakov, S.G. Isaev, M.Z. Tarasko, V.A.Roshchenko, G.D. Spriggs, J.M. Campbell, Energy Dependence of Relative Abundances and Periods of Delayed Neutrons from Neutron Induced Fission of U-235, U-238, Pu-239 in 6- and 8-group Model Representation, Progress in Nuclear Energy, 2002, v.41, No.1-4, pp.203-222.
V.M. Piksaikin, A.S. Egorov, K.V. Mitrofanov. THE ABSOLUTE TOTAL DELAYED NEUTRON YIELDS, RELATIVE ABUNDANCES AND HALF-LIVES OF DELAYED NEUTRON GROUPS FROM NEUTRON INDUCED FISSION OF 232Th, 233U, 236U, 239Pu AND 241Am. INDC(NDS) - 0646, 2013;

#Half-life [s]Relative abundance a(i)
155.6 0.032 ± 0.001
224.5 0.212 ± 0.007
316.3 0.097 ± 0.004
45.21 0.173 ± 0.007
52.37 0.300 ± 0.010
61.04 0.088 ± 0.004
70.424 0.076 ± 0.004
80.195 0.022 ± 0.001

Average Half-life : 10.29±0.20 s

Correlation matrix
a1T1a2T2a3T3a4T4a5T5a6T6a7T7a8T8
a1
1.00
T1
0.001.00
a2
0.000.001.00
T2
0.000.000.001.00
a3
0.000.00-0.670.001.00
T3
0.000.000.000.000.001.00
a4
0.000.000.540.00-0.720.001.00
T4
0.000.000.000.000.000.000.001.00
a5
0.000.000.260.000.170.00-0.550.001.00
T5
0.000.000.000.000.000.000.000.000.001.00
a6
0.000.000.060.00-0.050.000.200.00-0.450.001.00
T6
0.000.000.000.000.000.000.000.000.000.000.001.00
a7
0.000.000.050.00-0.040.000.110.00-0.140.00-0.140.001.00
T7
0.000.000.000.000.000.000.000.000.000.000.000.000.001.00
a8
0.000.000.010.00-0.010.000.010.00-0.010.00-0.020.00-0.020.001.00
T8
0.000.000.000.000.000.000.000.000.000.000.000.000.000.000.001.00

Energy: 15.8 MeV
6-Groups
Original Model - Roshchenko V.A., Piksaikin V.M., Kazakov L.E., Korolev G.G. RELATIVE YIELD OF DELAYED NEUTRONS AND HALF-LIFE OF THEIR PRECURSOR NUCLEI WITH FISSIONING OF 239PU BY 14.2-17.9 MEV NEUTRONS. Atomic Energy, 2006. V. 101. N.  6. pp. 897-900. 

#Half-life [s]Relative abundance a(i)
155.76 ± 0.690.054 ± 0.001
220.97 ± 0.270.186 ± 0.004
34.75 ± 0.090.241 ± 0.006
42.13 ± 0.050.362 ± 0.008
50.560 ± 0.0200.118 ± 0.003
60.215 ± 0.0060.039 ± 0.001

Average Half-life : 8.90 ± 0.12 s

Correlation matrix
a1T1a2T2a3T3a4T4a5T5a6T6
a1
1.00
T1
0.001.00
a2
0.000.881.00
T2
0.000.180.321.00
a3
0.000.170.190.261.00
T3
0.000.01-0.040.63-0.101.00
a4
0.000.570.650.43-0.040.321.00
T4
0.000.080.130.08-0.42-0.22-0.221.00
a5
0.000.430.500.330.020.07-0.070.591.00
T5
0.000.010.000.05-0.020.15-0.380.070.211.00
a6
0.000.080.090.050.010.010.010.07-0.060.141.00
T6
0.000.040.050.030.000.000.000.08-0.040.000.011.00

8-Groups
Expanded Model using a fixed set of Half-lives
V.M. Piksaikin, L.E. Kazakov, S.G. Isaev, M.Z. Tarasko, V.A.Roshchenko, G.D. Spriggs, J.M. Campbell, Energy Dependence of Relative Abundances and Periods of Delayed Neutrons from Neutron Induced Fission of U-235, U-238, Pu-239 in 6- and 8-group Model Representation, Progress in Nuclear Energy, 2002, v.41, No.1-4, pp.203-222.
V.M.Piksaikin et al. Generation of correlation and covariance matrices for the recommended Temporal DN parameters in 6- and 8- group models, EPJ Nuclear Sci. Technol., 6, 54,2020

#Half-life [s]Relative abundance a(i)
155.6000 0.0530 ± 0.0026
224.5000 0.1024 ± 0.0050
316.3000 0.0932 ± 0.0043
45.2100 0.1769 ± 0.0086
52.3700 0.3812 ± 0.0114
61.0400 0.0876 ± 0.0059
70.4240 0.0829 ± 0.0057
80.1950 0.0229 ± 0.0016

Average Half-life : 8.92 ± 0.21

Correlation matrix
a1T1a2T2a3T3a4T4a5T5a6T6a7T7a8T8
a1
1.00
T1
0.001.00
a2
0.000.001.00
T2
0.000.000.001.00
a3
0.000.00-0.810.001.00
T3
0.000.000.000.000.001.00
a4
0.000.000.520.00-0.730.001.00
T4
0.000.000.000.000.000.000.001.00
a5
0.000.000.120.000.210.00-0.660.001.00
T5
0.000.000.000.000.000.000.000.000.001.00
a6
0.000.000.060.00-0.070.000.250.00-0.540.001.00
T6
0.000.000.000.000.000.000.000.000.000.000.001.00
a7
0.000.000.050.00-0.050.000.130.00-0.150.00-0.180.001.00
T7
0.000.000.000.000.000.000.000.000.000.000.000.000.001.00
a8
0.000.000.010.00-0.010.000.010.00-0.010.00-0.020.00-0.030.001.00
T8
0.000.000.000.000.000.000.000.000.000.000.000.000.000.000.001.00


240PU
Energy: Fast Spectrum
6-Groups
Original Model - G. R. KEEPIN, T. F. WIMETT, and R. K. ZEIGLER, Delayed Neutrons from Fissionable Isotopes of Uranium, Plutonium, and Thorium,” Physical Review, 107, 4, 1044 (Aug. 15, 1957).

#Half-life [s]Relative abundance a(i)
153.6 ± 1.2000.028 ± 0.003
222.1 ± 0.3800.273 ± 0.004
35.14 ± 0.4200.192 ± 0.053
42.08 ± 0.1900.350 ± 0.020
50.511 ± 0.0770.128 ± 0.018
60.172 ± 0.0330.029 ± 0.006

Average Half-life : 9.32 ± 0.36 s

Correlation matrix
a1T1a2T2a3T3a4T4a5T5a6T6
a1
1
T1
01
a2
00.921
T2
00.460.511
a3
00.390.430.321
T3
00.170.10.64-0.351
a4
00.670.690.65-0.080.651
T4
00.040.06-0.03-0.610.130.121
a5
00.190.210.1300.05-0.010.371
T5
00.060.060.06-0.010.04-0.120.190.041
a6
00.020.020.01000.010.03-0.020.021
T6
00.020.020.010000.04-0.020.0101

8-Groups
Expanded Model using a fixed set of Half-lives
G. D. Spriggs, J. M. Campbell and V. M. Piksaikin, An 8-Group Neutron Model Based on a Consistent Set of Half-Lives, Los Alamos National Laboratory report LA-UR-98-1619, Rev. 3, (October 6, 1999).

#Half-life [s]Relative abundance a(i)
155.6 0.022 ± 0.003
224.5 0.207 ± 0.005
316.3 0.080 ± 0.002
45.21 0.161 ± 0.055
52.37 0.314 ± 0.009
61.04 0.105 ± 0.010
70.424 0.079 ± 0.017
80.195 0.032 ± 0.003

Average Half-life : 9.32 ± 0.36 s

Correlation matrix
a1T1a2T2a3T3a4T4a5T5a6T6a7T7a8T8
a1
1
T1
01
a2
001
T2
0001
a3
00-0.5801
T3
000001
a4
000.540-0.701
T4
00000001
a5
000.3700.150-0.4601
T5
0000000001
a6
000.10-0.0600.250-0.4701
T6
000000000001
a7
000.060-0.0400.120-0.10-0.1701
T7
00000000000001
a8
000.010-0.0100.020-0.010-0.030-0.0401
T8
0000000000000001


241AM
Energy: Thermal Spectrum
5-Groups
Original Model - R. W. WALDO, R. A. KARAM, R. A. MEYER, Delayed Neutron Yields: Time Dependent Measurements and a Predictive Model,” Physical Review C, 23, No. 3, 1113 (March 1981). R. W. WALDO, and R. A. KARAM, Measured Delayed Neutron Yields,” Trans. Amer. Nucl. Soc., 39, 879 (1981).

#Half-life [s]Relative abundance a(i)
154.5 ± 0.4620.036 ± 0.001
223.2 ± 0.1260.287 ± 0.008
34.56 ± 0.0670.303 ± 0.008
41.55 ± 0.0250.303 ± 0.004
50.264 ± 0.0130.071 ± 0.003

Average Half-life : 10.49 ± 0.21 s

Correlation matrix
a1T1a2T2a3T3a4T4a5T5
a1
1
T1
01
a2
00.941
T2
00.550.621
a3
00.60.660.441
T3
00.110.070.54-0.41
a4
00.590.60.64-0.040.721
T4
00.030.020.05-0.570.40.331
a5
00.060.060.0500.03-0.020.141
T5
00.040.050.0400.03-0.050.12-0.011

8-Groups
Expanded Model using a fixed set of Half-lives
G. D. Spriggs, J. M. Campbell and V. M. Piksaikin, An 8-Group Neutron Model Based on a Consistent Set of Half-Lives, Los Alamos National Laboratory report LA-UR-98-1619, Rev. 3, (October 6, 1999).

#Half-life [s]Relative abundance a(i)
155.6 0.0328 ± 0.0004
224.5 0.244 ± 0.003
316.3 0.055 ± 0.002
45.21 0.186 ± 0.004
52.37 0.306 ± 0.004
61.04 0.105 ± 0.003
70.424 0.037 ± 0.002
80.195 0.035 ± 0.002

Average Half-life : 10.52 ± 0.09 s

Correlation matrix
a1T1a2T2a3T3a4T4a5T5a6T6a7T7a8T8
a1
1
T1
01
a2
001
T2
0001
a3
00-0.6601
T3
000001
a4
000.440-0.6701
T4
00000001
a5
000.300.120-0.5901
T5
0000000001
a6
000.060-0.0500.250-0.5301
T6
000000000001
a7
000.020-0.0200.050-0.060-0.0801
T7
00000000000001
a8
000.010-0.0100.020-0.020-0.040-0.0201
T8
0000000000000001

Energy: 1.06 MeV
6-Groups
Original Model - Piksaikin et al., Relative Abundances and half-lives of their precursors for fission of 241Am nucleus by neutrons in the energy range from 1 to 5 MeV, Proc. Of XIIth Int. Seminar on Interaction of Neutrons with Nuclei Neutron Spectroscopy, Nuclear Structure, related Topics, Dubna, Russia, p. 62 (24-28 May 2011)

#Half-life [s]Relative abundance a(i)
154.00 ± 1.10.0436 ± 0.0009
223.92 ± 0.450.276 ± 0.006
36.13 ± 0.120.202 ± 0.004
42.31 ± 0.050.308 ± 0.006
50.49 ± 0.010.148 ± 0.003
60.179 ± 0.0040.0228 ± 0.0005

Average Half-life : 10.98 ± 0.21 s

Correlation matrix
a1T1a2T2a3T3a4T4a5T5a6T6
a1
1
T1
01
a2
00.931
T2
00.50.51
a3
00.460.50.391
T3
00.150.030.64-0.321
a4
00.630.610.66-0.050.681
T4
00.040.040.01-0.610.240.161
a5
00.230.250.180.020.080.020.381
T5
00.080.080.07-0.020.05-0.130.240.031
a6
00.020.020.01000.010.02-0.030.011
T6
00.020.020.010000.02-0.02001

8-Groups
Expanded Model using a fixed set of Half-lives
Piksaikin V.M., Egorov A.S., Mitrofanov K.V. The absolute total delayed neutron yields, relative abundances and half-lives of delayed neutron induced fission of 232Th, 233U, 236U, 239Pu, 241Am. International Nuclear Data Committee, INDC(NDS)-0646 (2013)

#Half-life [s]Relative abundance a(i)
155.6 0.03936 ± 3.80E-04
224.5 0.25981 ± 0.00253
316.3 0.02945 ± 0.00117
45.21 0.23698 ± 0.00334
52.37 0.20489 ± 0.00336
61.04 0.10677 ± 0.00332
70.424 0.07089 ± 0.00333
80.195 0.05185 ± 0.00256

Average Half-life : 10.91 ± 0.07 s

Correlation matrix
a1T1a2T2a3T3a4T4a5T5a6T6a7T7a8T8
a1
1
T1
01
a2
001
T2
0001
a3
00-0.501
T3
000001
a4
000.240-0.4801
T4
00000001
a5
000.3100.090-0.6701
T5
0000000001
a6
000.070-0.0300.210-0.501
T6
000000000001
a7
000.030-0.0200.090-0.10-0.1601
T7
00000000000001
a8
000.010-0.0100.030-0.020-0.050-0.0501
T8
0000000000000001

Energy: 15.8 MeV 6-groups
6-Groups
Original Model - Gremyachkin D.E., Piksaikin V.M., Egorov A.S., Mitrofanov K.V. Measurement of the Temporal Characteristics of Delayed Neutrons from Neutron Induced Fission of 241Am in the Energy Range from 14.2 to 18 MeV. Proceedings of the seminar ISINN-25, Dubna, Russian Federation 2017

#Half-life [s]Relative abundance a(i)
155.1 ± 0.50.042 ± 0.0003
224.4 ± 0.20.229 ± 0.002
35.26 ± 0.040.427 ± 0.003
43.23 ± 0.030.215 ± 0.002
50.49 ± 0.0040.067 ± 0.001
60.175 ± 0.0020.019 ± 0.0002

Average Half-life : 10.88 ± 0.08 s

Correlation matrix
a1T1a2T2a3T3a4T4a5T5a6T6
a1
1
T1
01
a2
00.031
T2
0-0.01-0.31
a3
0-0.020.320.271
T3
00.03-0.260.220.11
a4
0-0.010.150.11-0.110.111
T4
00-0.030.08-0.01-0.310.021
a5
000.01000.0300.011
T5
000.01000.0300.0101
a6
00000000001
T6
000000000001

8-Groups
Expanded Model using a fixed set of Half-lives
V.M. Piksaikin, L.E. Kazakov, S.G. Isaev, M.Z. Tarasko, V.A.Roshchenko, G.D. Spriggs, J.M. Campbell, Energy Dependence of Relative Abundances and Periods of Delayed Neutrons from Neutron Induced Fission of U-235, U-238, Pu-239 in 6- and 8-group Model Representation, Progress in Nuclear Energy, 2002, v.41, No.1-4, pp.203-222.
V.M.Piksaikin et al. Generation of correlation and covariance matrices for the recommended Temporal DN parameters in 6- and 8- group models, EPJ Nuclear Sci. Technol., 6, 54,2020

#Half-life [s]Relative abundance a(i)
155.6 0.04115 ± 0.00036
224.5 0.22474 ± 0.00194
316.3 0.00685 ± 0.00046
45.21 0.48492 ± 0.00372
52.37 0.17129 ± 0.00315
61.04 0.01906 ± 0.00126
70.424 0.02567 ± 0.00174
80.195 0.02632 ± 0.00182

Average Half-life : 10.87 ± 0.06 s

Correlation matrix
a1T1a2T2a3T3a4T4a5T5a6T6a7T7a8T8
a1
1
T1
01
a2
001
T2
0001
a3
00-0.2901
T3
000001
a4
000.330-0.2801
T4
00000001
a5
000.3900.070-0.5901
T5
0000000001
a6
0000000.070-0.2101
T6
000000000001
a7
0000-0.0100.070-0.130-0.0301
T7
00000000000001
a8
0000000.030-0.050-0.010-0.0201
T8
0000000000000001


241PU
Energy: Thermal Spectrum
5-Groups
Original Model - S. A. COX, Delayed-Neutron Studies from the Thermal-Neutron-Induced Fission of 241Pu,” Physical Review, 123, No. 5, 1735 (September 1, 1961).

#Half-life [s]Relative abundance a(i)
154 ± 1.0000.010 ± 0.003
223.2 ± 0.5000.233 ± 0.006
35.6 ± 0.6000.176 ± 0.026
41.97 ± 0.1000.396 ± 0.051
50.43 ± 0.0400.185 ± 0.019

Average Half-life : 7.77 ± 0.32 s

Correlation matrix
a1T1a2T2a3T3a4T4a5T5
a1
1
T1
01
a2
-0.4601
T2
-0.1500.761
a3
0.180-0.090.221
T3
-0.0400.310.460.161
a4
0.080-0.020.070.66-0.461
T4
-0.0600.530.760.50.060.571
a5
-0.0100.070.10.05-0.620.330.111
T5
-0.0300.230.320.120.010.090.090.431

7-Groups
Expanded Model using a fixed set of Half-lives
G. D. Spriggs, J. M. Campbell and V. M. Piksaikin, An 8-Group Neutron Model Based on a Consistent Set of Half-Lives, Los Alamos National Laboratory report LA-UR-98-1619, Rev. 3, (October 6, 1999).

#Half-life [s]Relative abundance a(i)
155.6 0.011 ± 0.003
224.5 0.166 ± 0.003
316.3 0.095 ± 0.011
45.21 0.100 ± 0.025
52.37 0.382 ± 0.043
61.04 0.073 ± 0.030
70.424 0.174 ± 0.012

Average Half-life : 7.78 ± 0.32 s

Correlation matrix
a1T1a2T2a3T3a4T4a5T5a6T6a7T7
a1
1
T1
01
a2
001
T2
0001
a3
00-0.1801
T3
000001
a4
000.530-0.5301
T4
00000001
a5
000.7300.230-0.101
T5
0000000001
a6
000.070-0.0100.150-0.1701
T6
000000000001
a7
000.240-0.0300.290-0.030-0.1801
T7
00000000000001

Energy: Fission Spectrum
6-Groups
Original Model - A. N. GUDKOV et al., Measurement of the Delayed-Neutron Yields in the Fission of 233U, 236U, 237Np, 240Pu, and 241Pu by Neutrons from the Spectrum of a Fast Reactor,” At. Energ., 66, No. 2, 100 (1989).

#Half-life [s]Relative abundance a(i)
155.9 ± 0.0000.017 ± 0.003
223.0 ± 0.0000.218 ± 0.022
35.64 ± 0.0000.179 ± 0.019
42.10 ± 0.0000.362 ± 0.040
50.578 ± 0.0000.189 ± 0.042
60.201 ± 0.0000.035 ± 0.014

Average Half-life : 7.85 ± 0.54 s

Correlation matrix
a1T1a2T2a3T3a4T4a5T5a6T6
a1
1
T1
01
a2
001
T2
0001
a3
000.1201
T3
000001
a4
000.680-0.4601
T4
00000001
a5
000.0800.360-0.4301
T5
0000000001
a6
000.0100.01000-0.0801
T6
000000000001

8-Groups
Expanded Model using a fixed set of Half-lives
G. D. Spriggs, J. M. Campbell and V. M. Piksaikin, An 8-Group Neutron Model Based on a Consistent Set of Half-Lives, Los Alamos National Laboratory report LA-UR-98-1619, Rev. 3, (October 6, 1999).

#Half-life [s]Relative abundance a(i)
155.6 0.016 ± 0.002
224.5 0.175 ± 0.019
316.3 0.055 ± 0.012
45.21 0.170 ± 0.018
52.37 0.280 ± 0.035
61.04 0.166 ± 0.033
70.424 0.113 ± 0.035
80.195 0.024 ± 0.006

Average Half-life : 7.85 ± 0.53 s

Correlation matrix
a1T1a2T2a3T3a4T4a5T5a6T6a7T7a8T8
a1
1
T1
01
a2
001
T2
0001
a3
00-0.5301
T3
000001
a4
000.570-0.6601
T4
00000001
a5
000.3800.140-0.4101
T5
0000000001
a6
000.210-0.100.360-0.4901
T6
000000000001
a7
000.110-0.0600.12000-0.2901
T7
00000000000001
a8
000.010-0.0100.0100.010-0.030-0.0301
T8
0000000000000001


242AM
Energy: Thermal Spectrum
6-Groups
Original Model - R. W. WALDO, R. A. KARAM, R. A. MEYER, Delayed Neutron Yields: Time Dependent Measurements and a Predictive Model,” Physical Review C, 23, No. 3, 1113 (March 1981). R. W. WALDO, and R. A. KARAM, Measured Delayed Neutron Yields,” Trans. Amer. Nucl. Soc., 39, 879 (1981).

#Half-life [s]Relative abundance a(i)
154.4 ± 0.2100.026 ± 0.002
223.1 ± 0.0850.284 ± 0.019
37.45 ± 0.4300.120 ± 0.013
42.82 ± 0.0770.355 ± 0.038
51.06 ± 0.1300.173 ± 0.019
60.513 ± 0.1500.044 ± 0.065

Average Half-life : 10.04 ± 0.48 s

Correlation matrix
a1T1a2T2a3T3a4T4a5T5a6T6
a1
1
T1
01
a2
00.891
T2
00.270.251
a3
00.280.30.341
T3
00.09-0.060.71-0.21
a4
00.660.670.570.060.491
T4
00.060.080.07-0.570.15-0.051
a5
00.310.340.220.010.1-0.060.541
T5
0-0.01-0.020.030.020.07-0.290.060.161
a6
00.060.070.0400.020.010.09-0.050.081
T6
00.030.030.0200.01-0.010.07-0.02-0.0201

7-Groups
Expanded Model using a fixed set of Half-lives
G. D. Spriggs, J. M. Campbell and V. M. Piksaikin, An 8-Group Neutron Model Based on a Consistent Set of Half-Lives, Los Alamos National Laboratory report LA-UR-98-1619, Rev. 3, (October 6, 1999).

#Half-life [s]Relative abundance a(i)
155.6 0.0210 ± 0.0004
224.5 0.245 ± 0.018
316.3 0.060 ± 0.008
45.21 0.205 ± 0.025
52.37 0.261 ± 0.029
61.04 0.179 ± 0.040
70.424 0.030 ± 0.056

Average Half-life : 10.03 ± 0.48 s

Correlation matrix
a1T1a2T2a3T3a4T4a5T5a6T6a7T7
a1
1
T1
01
a2
001
T2
0001
a3
00-0.5901
T3
000001
a4
000.580-0.701
T4
00000001
a5
000.2600.170-0.501
T5
0000000001
a6
000.180-0.100.360-0.6101
T6
000000000001
a7
000.020-0.0100.030-0.010-0.101
T7
00000000000001


242PU
Energy: Fast Spectrum
6-Groups
Original Model - R. W. WALDO, R. A. KARAM, R. A. MEYER, Delayed Neutron Yields: Time Dependent Measurements and a Predictive Model,” Physical Review C, 23, No. 3, 1113 (March 1981). R. W. WALDO, and R. A. KARAM, Measured Delayed Neutron Yields,” Trans. Amer. Nucl. Soc., 39, 879 (1981).

#Half-life [s]Relative abundance a(i)
151.7 ± 1.0000.011 ± 0.001
223.5 ± 1.2000.161 ± 0.053
316.9 ± 5.8000.031 ± 0.005
45.46 ± 0.2400.164 ± 0.015
51.75 ± 0.1500.367 ± 0.036
60.312 ± 0.1200.266 ± 0.086

Average Half-life : 6.51 ± 1.28 s

Correlation matrix
a1T1a2T2a3T3a4T4a5T5a6T6
a1
1
T1
01
a2
00.651
T2
0-0.250.061
a3
00.03-0.140.331
T3
00.14-0.31-0.1801
a4
00.320.410.060.040.11
T4
00.03-0.020.49-0.070.32-0.411
a5
00.490.640.380.070.050.090.561
T5
00.10.110.080.010.05-0.590.40.091
a6
00.270.360.120.0400.050.140.160.411
T6
00.110.150.050.020.01-0.030.08-0.130.37-0.021

8-Groups
Expanded Model using a fixed set of Half-lives
G. D. Spriggs, J. M. Campbell and V. M. Piksaikin, An 8-Group Neutron Model Based on a Consistent Set of Half-Lives, Los Alamos National Laboratory report LA-UR-98-1619, Rev. 3, (October 6, 1999).

#Half-life [s]Relative abundance a(i)
155.6 0.0087 ± 0.0002
224.5 0.139 ± 0.003
316.3 0.070 ± 0.001
45.21 0.097 ± 0.002
52.37 0.345 ± 0.003
61.04 0.00062 ± 2.00E-05
70.424 0.299 ± 0.005
80.195 0.041 ± 0.001

Average Half-life : 6.48 ± 0.08 s

Correlation matrix
a1T1a2T2a3T3a4T4a5T5a6T6a7T7a8T8
a1
1
T1
01
a2
001
T2
0001
a3
00-0.1801
T3
000001
a4
000.510-0.5201
T4
00000001
a5
000.700.250-0.1601
T5
0000000001
a6
00000000001
T6
000000000001
a7
000.400.0100.40-0.010001
T7
00000000000001
a8
000.020000.0100.02000-0.1101
T8
0000000000000001

Energy: 14.7 MeV
6-Groups
Original Model - L. V. EAST, R. H. AUGUSTON, and H. O. MENLOVE, Delayed Neutron Abundances and Half-Lives for 14.7-MeV Fission, excerpt from Los Alamos National Laboratory Program Status Report LA-4605-MS (September-December, 1970), p. 15. L. V. EAST, R. H. AUGUSTSON, H. O. MENLOVE, and C. F. MASTERS, Delayed- Neutron Abundances and Half-Lives from 14.7-MeV Fission, Trans Amer. Nucl. Soc., 13, 760 (November, 1970).

#Half-life [s]Relative abundance a(i)
155.4 ± 4.5000.022 ± 0.004
221.8 ± 0.5000.168 ± 0.002
35.50 ± 0.3000.150 ± 0.015
42.20 ± 0.1000.366 ± 0.009
50.760 ± 0.0600.159 ± 0.010
60.250 ± 0.0100.135 ± 0.009

Average Half-life : 6.67 ± 0.28 s

Correlation matrix
a1T1a2T2a3T3a4T4a5T5a6T6
a1
1
T1
01
a2
00.891
T2
00.420.341
a3
00.310.340.271
T3
00.190.010.68-0.351
a4
00.670.640.64-0.030.61
T4
00.030.06-0.03-0.630.13-0.031
a5
00.270.280.200.09-0.030.431
T5
00.01-0.010.03-0.010.06-0.260.140.091
a6
00.150.160.110.020.050.070.14-0.10.161
T6
00.10.110.0700.030.010.17-0.090.06-0.041

8-Groups
Expanded Model using a fixed set of Half-lives
G. D. Spriggs, J. M. Campbell and V. M. Piksaikin, An 8-Group Neutron Model Based on a Consistent Set of Half-Lives, Los Alamos National Laboratory report LA-UR-98-1619, Rev. 3, (October 6, 1999).

#Half-life [s]Relative abundance a(i)
155.6 0.022 ± 0.005
224.5 0.097 ± 0.002
316.3 0.090 ± 0.002
45.21 0.108 ± 0.018
52.37 0.366 ± 0.004
61.04 0.111 ± 0.002
70.424 0.143 ± 0.010
80.195 0.064 ± 0.006

Average Half-life : 6.67 ± 0.28 s

Correlation matrix
a1T1a2T2a3T3a4T4a5T5a6T6a7T7a8T8
a1
1
T1
01
a2
001
T2
0001
a3
00-0.6101
T3
000001
a4
000.490-0.6701
T4
00000001
a5
000.4200.120-0.4501
T5
0000000001
a6
000.080-0.0400.240-0.4201
T6
000000000001
a7
000.120-0.0600.170-0.080-0.2701
T7
00000000000001
a8
000.030-0.0100.0200.010-0.040-0.1101
T8
0000000000000001


243AM
Energy: Fast Spectrum
7-Groups
Original Model - W. S. CHARLTON, Delayed Neutron Emission Measurements from Fast Fission of Actinide Waste Isotopes,” Master’s Thesis, Texas A&M University (August, 1998).

#Half-life [s]Relative abundance a(i)
155.9 ± 1.8000.017 ± 0.005
224.5 ± 0.7800.226 ± 0.011
316.7 ± 0.3600.088 ± 0.006
44.59 ± 0.0610.206 ± 0.011
51.77 ± 0.0270.335 ± 0.011
60.774 ± 0.0350.088 ± 0.009
70.283 ± 0.0050.041 ± 0.008

Average Half-life : 9.54 ± 0.43 s

Correlation matrix
a1T1a2T2a3T3a4T4a5T5a6T6a7T7
a1
1
T1
01
a2
00.641
T2
0-0.1-0.051
a3
00.13-0.180.721
T3
00.1-0.51-0.140.061
a4
00.360.310.070.10.091
T4
00.13-0.120.12-0.120.55-0.311
a5
00.550.520.260.160.04-0.090.531
T5
00.110.100.04-0.01-0.560.160.141
a6
00.080.080.030.03000.05-0.080.171
T6
00.060.050.030.010.010.010.08-0.10.0201
a7
00.20.210.060.07-0.03-0.020.03-0.040.45-0.130.181
T7
00.020.020.010.01000.01-0.020.05-0.010-0.021

8-Groups
Expanded Model using a fixed set of Half-lives
G. D. Spriggs, J. M. Campbell and V. M. Piksaikin, An 8-Group Neutron Model Based on a Consistent Set of Half-Lives, Los Alamos National Laboratory report LA-UR-98-1619, Rev. 3, (October 6, 1999).

#Half-life [s]Relative abundance a(i)
155.6 0.018 ± 0.006
224.5 0.220 ± 0.012
316.3 0.098 ± 0.002
45.21 0.121 ± 0.009
52.37 0.316 ± 0.013
61.04 0.170 ± 0.003
70.424 0.043 ± 0.011
80.195 0.015 ± 0.002

Average Half-life : 9.54 ± 0.44 s

Correlation matrix
a1T1a2T2a3T3a4T4a5T5a6T6a7T7a8T8
a1
1
T1
01
a2
001
T2
0001
a3
00-0.4301
T3
000001
a4
000.490-0.6301
T4
00000001
a5
000.4600.120-0.4101
T5
0000000001
a6
000.160-0.0500.340-0.5201
T6
000000000001
a7
000.030-0.0100.040-0.010-0.1201
T7
00000000000001
a8
000.010000.01000-0.020-0.0101
T8
0000000000000001


245CM
Energy: Thermal Spectrum
6-Groups
Original Model - R. W. WALDO, R. A. KARAM, R. A. MEYER, Delayed Neutron Yields: Time Dependent Measurements and a Predictive Model,” Physical Review C, 23, No. 3, 1113 (March 1981). R. W. WALDO, and R. A. KARAM, Measured Delayed Neutron Yields,” Trans. Amer. Nucl. Soc., 39, 879 (1981).

#Half-life [s]Relative abundance a(i)
151.9 ± 0.3500.024 ± 0.002
222.9 ± 0.8600.303 ± 0.020
36.66 ± 0.0900.091 ± 0.029
43.29 ± 0.1700.294 ± 0.052
51.29 ± 0.1800.230 ± 0.027
60.513 ± 0.1500.059 ± 0.100

Average Half-life : 10.06 ± 0.60 s

Correlation matrix
a1T1a2T2a3T3a4T4a5T5a6T6
a1
1
T1
01
a2
00.881
T2
00.180.321
a3
00.170.190.261
T3
00.01-0.040.63-0.11
a4
00.570.650.43-0.040.321
T4
00.080.130.08-0.42-0.22-0.221
a5
00.430.50.330.020.07-0.070.591
T5
00.0100.05-0.020.15-0.380.070.211
a6
00.080.090.050.010.010.010.07-0.060.141
T6
00.040.050.030000.08-0.0400.011

7-Groups
Expanded Model using a fixed set of Half-lives
G. D. Spriggs, J. M. Campbell and V. M. Piksaikin, An 8-Group Neutron Model Based on a Consistent Set of Half-Lives, Los Alamos National Laboratory report LA-UR-98-1619, Rev. 3, (October 6, 1999).

#Half-life [s]Relative abundance a(i)
155.6 0.016 ± 0.004
224.5 0.269 ± 0.020
316.3 0.045 ± 0.001
45.21 0.204 ± 0.046
52.37 0.255 ± 0.040
61.04 0.179 ± 0.050
70.424 0.033 ± 0.084

Average Half-life : 10.05 ± 0.61 s

Correlation matrix
a1T1a2T2a3T3a4T4a5T5a6T6a7T7
a1
1
T1
01
a2
001
T2
0001
a3
00-0.4901
T3
000001
a4
000.580-0.6401
T4
00000001
a5
000.3500.130-0.4201
T5
0000000001
a6
000.220-0.100.380-0.5501
T6
000000000001
a7
000.020-0.0100.030-0.010-0.1101
T7
00000000000001


249CF
4-Groups
Original Model - R. W. WALDO, R. A. KARAM, R. A. MEYER, Delayed Neutron Yields: Time Dependent Measurements and a Predictive Model,” Physical Review C, 23, No. 3, 1113 (March 1981). R. W. WALDO, and R. A. KARAM, Measured Delayed Neutron Yields,” Trans. Amer. Nucl. Soc., 39, 879 (1981).

#Half-life [s]Relative abundance a(i)
153.9 ± 0.0840.029 ± 0.002
222.8 ± 0.0080.353 ± 0.026
34.13 ± 0.0910.383 ± 0.032
41.28 ± 0.1500.236 ± 0.026

Average Half-life : 11.47 ± 0.62 s

Correlation matrix
a1T1a2T2a3T3a4T4
a1
1
T1
01
a2
00.921
T2
00.480.611
a3
00.740.810.551
T3
00.0100.48-0.331
a4
00.460.490.540.040.691
T4
00.030.030.06-0.410.390.321

6-Groups
Expanded Model using a fixed set of Half-lives
G. D. Spriggs, J. M. Campbell and V. M. Piksaikin, An 8-Group Neutron Model Based on a Consistent Set of Half-Lives, Los Alamos National Laboratory report LA-UR-98-1619, Rev. 3, (October 6, 1999).

#Half-life [s]Relative abundance a(i)
155.6 0.024 ± 0.0005
224.5 0.293 ± 0.023
316.3 0.064 ± 0.011
45.21 0.228 ± 0.028
52.37 0.265 ± 0.026
61.04 0.128 ± 0.017

Average Half-life : 11.48 ± 0.61 s

Correlation matrix
a1T1a2T2a3T3a4T4a5T5a6T6
a1
1
T1
01
a2
001
T2
0001
a3
00-0.5601
T3
000001
a4
000.570-0.6801
T4
00000001
a5
000.3100.150-0.4701
T5
0000000001
a6
000.10-0.0700.270-0.5501
T6
000000000001


252CF
Energy: Spontaneous Fission
4-Groups
Original Model - E. T. CHULICK, P. L. REEDER, E. EICHLER, and C. E. BEMIS Jr., Redetermination of Delayed Neutrons from 252Cf,” Radiochimica Acta, 12, No. 3, 164 (1969).

#Half-life [s]Relative abundance a(i)
126.8 ± 1.1000.310 ± 0.010
26.10 ± 1.4000.220 ± 0.020
32.00 ± 0.3000.300 ± 0.030
40.500 ± 0.1000.170 ± 0.050

Average Half-life : 10.34 ± 0.56 s

Correlation matrix
a1T1a2T2a3T3a4T4
a1
1
T1
01
a2
0-0.011
T2
00.57-0.681
a3
00.36-0.60.731
T3
00.06-0.780.440.151
a4
00.04-0.170.1-0.30.431
T4
00.03-0.060.06-0.330.210.031

7-Groups
Expanded Model using a fixed set of Half-lives
G. D. Spriggs, J. M. Campbell and V. M. Piksaikin, An 8-Group Neutron Model Based on a Consistent Set of Half-Lives, Los Alamos National Laboratory report LA-UR-98-1619, Rev. 3, (October 6, 1999).

#Half-life [s]Relative abundance a(i)
155.6 0.014 ± 0.006
224.5 0.318 ± 0.006
316.3 0.001 ± 0.024
45.21 0.209 ± 0.018
52.37 0.200 ± 0.004
61.04 0.144 ± 0.031
70.424 0.112 ± 0.044

Average Half-life : 10.38 ± 0.55 s

Correlation matrix
a1T1a2T2a3T3a4T4a5T5a6T6a7T7
a1
1
T1
01
a2
001
T2
0001
a3
00-0.0101
T3
000001
a4
000.330-0.0101
T4
00000001
a5
000.73000-0.2701
T5
0000000001
a6
000.180000.320-0.301
T6
000000000001
a7
000.090000.120-0.020-0.1701
T7
00000000000001