ADOPTED LEVELS, GAMMAS for 251Es
Author: C. Morse | Citation: Nucl. Data Sheets 189, 111 (2023) | Cutoff date: 23-Sep-2022
Full ENSDF file | Adopted Levels (PDF version)
Q(β-)=-1447 keV 15 | S(n)= 6785 keV SY | S(p)= 3948 keV 5 | Q(α)= 6597.1 keV 10 | ||
Reference: 2021Wa16 |
References: | |||
A | 251Fm ε decay | B | 255Md α decay |
C | 250Cf(α,t) |
E(level) (keV) | XREF | Jπ(level) | T1/2(level) | E(γ) (keV) | I(γ) | M(γ) | Final Levels | |
0 | ABC | 3/2- | 33 h 1 % α = 0.5 1 % ε = 99.5 1 | |||||
8.34 23 | AB | (7/2)+ | ||||||
31.70 20 | ABC | 5/2- | ||||||
55.85 23 | AB | (9/2)+ | 47.48 6 | 100 | M1+E2 | 8.34 | (7/2)+ | |
76.1 3 | ABC | 7/2- | ||||||
114.08 24 | A | (11/2+) | ||||||
182.6 3 | A C | (13/2+) | ||||||
263.0 4 | A | (15/2+) | ||||||
411 2 | C | (1/2-) | ||||||
452 2 | C | (5/2-) | ||||||
461.40 22 | AB | 7/2- | 385.3 2 405.55 9 429.7 1 453.06 9 | 2.1 2 68.2 34 5.7 5 100 | (M1+E2) E1+M2 (M1+E2) E1+M2 | 76.1 55.85 31.70 8.34 | 7/2- (9/2)+ 5/2- (7/2)+ | |
523 2 | BC | (9/2-) | ||||||
548 2 | C | (7/2-) | ||||||
548 2 | C | (9/2-) | ||||||
661 3 | C | (1/2+) | ||||||
777.94 24 | A | (9/2)+ | 664.0 3 722.1 2 769.6 1 | 4.3 8 21 2 100 | (M1+E2) M1+E2 M1 | 114.08 55.85 8.34 | (11/2+) (9/2)+ (7/2)+ | |
889.10 24 | A | (11/2)+ | 706.3 2 775.0 1 833.3 1 880.8 1 | 1.1 1 ≈3.9 29 2 100 | (M1+E2) (M1+E2) M1+E2 E2 | 182.6 114.08 55.85 8.34 | (13/2+) (11/2+) (9/2)+ (7/2)+ | |
942 4 | C | (13/2)+ | ||||||
957.52 24 | A C | (13/2)+ | 694.5 3 775.0 1 843.4 1 901.6 1 | 12 2 ≈32 92 8 100 | (M1+E2) (M1+E2) M1+E2 E2 | 263.0 182.6 114.08 55.85 | (15/2+) (13/2+) (11/2+) (9/2)+ | |
E(level) (keV) | XREF | Jπ(level) | T1/2(level) | E(γ) (keV) | I(γ) | M(γ) | Final Levels | |
1238.95 24 | A | (11/2)+ | 281.4 1 349.9 1 461.0 1 1056.2 4 1124.9 2 1183.0 2 1230.6 2 | 8.6 6 100 11 1 0.7 1 3.3 4 8.8 6 16 1 | M1 M1 (M1+E2) (M1+E2) (M1+E2) (M1+E2) E2 | 957.52 889.10 777.94 182.6 114.08 55.85 8.34 | (13/2)+ (11/2)+ (9/2)+ (13/2+) (11/2+) (9/2)+ (7/2)+ | |
1264.94 24 | A | (11/2)+ | 307.4 1 375.8 1 487.1 2 1151.0 2 1209.1 2 1256.6 2 | 9.7 8 100 3.0 5 4.1 5 9.5 8 18 1 | (M1+E2) M1 (M1+E2) (M1+E2) (M1+E2) E2 | 957.52 889.10 777.94 114.08 55.85 8.34 | (13/2)+ (11/2)+ (9/2)+ (11/2+) (9/2)+ (7/2)+ | |
1301.4 3 | A | (7/2+,9/2,11/2) | 1245.6 4 1293.0 3 | 16 2 100 | 55.85 8.34 | (9/2)+ (7/2)+ | ||
1307.1 3 | A | (7/2+,9/2,11/2+) | 1193.0 2 1251.2 2 1298.8 3 | 21 2 45 4 100 | 114.08 55.85 8.34 | (11/2+) (9/2)+ (7/2)+ | ||
1357.0 3 | A | (7/2+,9/2,11/2+) | 1242.8 4 1301.2 3 1348.6 3 | 52 5 100 1 33 3 | 114.08 55.85 8.34 | (11/2+) (9/2)+ (7/2)+ |
E(level): Determined by least-squares fit to the γ-ray energies, and assuming that the 5/2- member of the π3/2-[521] band decays to the ground state by a 31.7 2 keV transition (c.f. 251Fm ε decay), unless otherwise noted.
E(level) (keV) | Jπ(level) | T1/2(level) | E(γ) | I(γ) | M(γ) | Final Levels | |
Band 1 - π3/2-[521] | |||||||
0 | 3/2- | 33 h 1 % α = 0.5 1 % ε = 99.5 1 | |||||
31.70 20 | 5/2- | ||||||
76.1 3 | 7/2- | ||||||
E(level) (keV) | Jπ(level) | T1/2(level) | E(γ) | I(γ) | M(γ) | Final Levels | |
Band 2 - π7/2+[633] | |||||||
8.34 23 | (7/2)+ | ||||||
55.85 23 | (9/2)+ | ||||||
114.08 24 | (11/2+) | ||||||
182.6 3 | (13/2+) | ||||||
263.0 4 | (15/2+) | ||||||
E(level) (keV) | Jπ(level) | T1/2(level) | E(γ) | I(γ) | M(γ) | Final Levels | |
Band 3 - π1/2-[521] | |||||||
411 2 | (1/2-) | ||||||
452 2 | (5/2-) | ||||||
548 2 | (7/2-) | ||||||
548 2 | (9/2-) | ||||||
E(level) (keV) | Jπ(level) | T1/2(level) | E(γ) | I(γ) | M(γ) | Final Levels | |
Band 4 - π7/2-[514] | |||||||
461.40 22 | 7/2- | ||||||
523 2 | (9/2-) | ||||||
E(level) (keV) | Jπ(level) | T1/2(level) | E(γ) | I(γ) | M(γ) | Final Levels | |
Band 5 - |[π7/2+[633]~#2+|]11/2+ γ-vibrational band | |||||||
889.10 24 | (11/2)+ | ||||||
957.52 24 | (13/2)+ | ||||||
E(level) (keV) | Jπ(level) | T1/2(level) | E(γ) | I(γ) | M(γ) | Final Levels | |
Band 6 - π9/2+[624] | |||||||
777.94 24 | (9/2)+ | ||||||
942 4 | (13/2)+ |
E(level) (keV) | Jπ(level) | T1/2(level) | E(γ) (keV) | Multipolarity | Mixing Ratio | Conversion Coefficient | Additional Data |
55.85 | (9/2)+ | 47.48 6 | M1+E2 | 0.243 +25-27 | 125 | α=125 9, α(L)=92 7, α(M)=24.1 18, α(N)=6.7 5, α(O)=1.73 13, α(P)=0.311 20, α(Q)=0.01213 20 | |
461.40 | 7/2- | 385.3 2 | (M1+E2) | 0.54 | α=0.54 40, α(K)=0.39 34, α(L)=0.107 48, α(M)=0.027 11, α(N)=0.0076 30, α(O)=0.00197 81, α(P)=3.7×10-4 17, α(Q)=1.7E-5 14 | ||
7/2- | 405.55 9 | E1+M2 | 0.179 9 | 0.091 | α=0.091 7, α(K)=0.066 5, α(L)=0.0187 15, α(M)=0.0048 4, α(N)=0.00136 11, α(O)=0.00035 3, α(P)=6.7×10-5 6, α(Q)=3.5E-6 3 | ||
7/2- | 429.7 1 | (M1+E2) | 0.40 | α=0.40 30, α(K)=0.29 25, α(L)=0.078 38, α(M)=0.0196 86, α(N)=0.0055 24, α(O)=0.00142 64, α(P)=2.7×10-4 13, α(Q)=1.3E-5 10 | |||
7/2- | 453.06 9 | E1+M2 | 0.236 +17-18 | 0.100 | α=0.100 12, α(K)=0.072 8, α(L)=0.0204 25, α(M)=0.0053 7, α(N)=0.00147 18, α(O)=0.00039 5, α(P)=7.3×10-5 9, α(Q)=3.9E-6 5 | ||
777.94 | (9/2)+ | 664.0 3 | (M1+E2) | 0.125 | α=0.125 88, α(K)=0.095 72, α(L)=0.023 13, α(M)=0.0056 30, α(N)=0.00157 82, α(O)=4.1×10-4 22, α(P)=7.8E-5 43, α(Q)=4.0E-6 29 | ||
(9/2)+ | 722.1 2 | M1+E2 | 0.50 +28-35 | 0.142 | α=0.142 25, α(K)=0.110 21, α(L)=0.024 4, α(M)=0.0059 9, α(N)=0.00163 24, α(O)=0.00043 7, α(P)=8.2×10-5 13, α(Q)=4.6E-6 9 | ||
(9/2)+ | 769.6 1 | M1 | 0.1429 | α=0.1429, α(K)=0.1117 16, α(L)=0.0234 4, α(M)=0.00573 8, α(N)=0.001592 23, α(O)=0.000417 6, α(P)=8.07×10-5 12, α(Q)=4.60E-6 7 | |||
889.10 | (11/2)+ | 706.3 2 | (M1+E2) | 0.106 | α=0.106 74, α(K)=0.081 60, α(L)=0.019 11, α(M)=0.0047 25, α(N)=0.00132 69, α(O)=3.4×10-4 19, α(P)=6.6E-5 37, α(Q)=3.4E-6 25 | ||
(11/2)+ | 775.0 1 | (M1+E2) | 0.084 | α=0.084 57, α(K)=0.064 46, α(L)=0.0148 82, α(M)=0.0037 20, α(N)=1.02×10-3 54, α(O)=2.7E-4 15, α(P)=5.1E-5 29, α(Q)=2.7E-6 19 | |||
(11/2)+ | 833.3 1 | M1+E2 | 2.21 +40-28 | 0.039 | α=0.039 4, α(K)=0.028 4, α(L)=0.0078 6, α(M)=0.00197 14, α(N)=0.00055 4, α(O)=0.000142 10, α(P)=2.66×10-5 20, α(Q)=1.21E-6 13 | ||
(11/2)+ | 880.8 1 | E2 | 0.0209 | α=0.0209, α(K)=0.01447 21, α(L)=0.00476 7, α(M)=0.001231 18, α(N)=0.000344 5, α(O)=8.86×10-5 13, α(P)=1.627E-5 23, α(Q)=6.28E-7 9 | |||
957.52 | (13/2)+ | 694.5 3 | (M1+E2) | 0.111 | α=0.111 78, α(K)=0.084 63, α(L)=0.020 11, α(M)=0.0050 26, α(N)=0.00138 73, α(O)=3.6×10-4 19, α(P)=6.9E-5 38, α(Q)=3.5E-6 26 | ||
(13/2)+ | 775.0 1 | (M1+E2) | 0.084 | α=0.084 57, α(K)=0.064 46, α(L)=0.0148 82, α(M)=0.0037 20, α(N)=1.02×10-3 54, α(O)=2.7E-4 15, α(P)=5.1E-5 29, α(Q)=2.7E-6 19 | |||
(13/2)+ | 843.4 1 | M1+E2 | 0.72 +22-20 | 0.081 | α=0.081 12, α(K)=0.063 10, α(L)=0.0138 17, α(M)=0.0034 4, α(N)=0.00095 11, α(O)=0.00025 3, α(P)=4.8×10-5 6, α(Q)=2.6E-6 4 | ||
(13/2)+ | 901.6 1 | E2 | 0.0200 | α=0.0200, α(K)=0.01392 20, α(L)=0.00449 7, α(M)=0.001158 17, α(N)=0.000323 5, α(O)=8.34×10-5 12, α(P)=1.533E-5 22, α(Q)=6.00E-7 9 | |||
1238.95 | (11/2)+ | 281.4 1 | M1 | 2.24 | α=2.24, α(K)=1.741 25, α(L)=0.371 6, α(M)=0.0914 13, α(N)=0.0254 4, α(O)=0.00666 10, α(P)=0.001288 18, α(Q)=7.36×10-5 11 | ||
(11/2)+ | 349.9 1 | M1 | 1.223 | α=1.223, α(K)=0.953 14, α(L)=0.202 3, α(M)=0.0498 7, α(N)=0.01384 20, α(O)=0.00363 5, α(P)=0.000702 10, α(Q)=4.00×10-5 6 | |||
(11/2)+ | 461.0 1 | (M1+E2) | 0.33 | α=0.33 25, α(K)=0.24 21, α(L)=0.063 32, α(M)=0.0160 73, α(N)=0.0044 21, α(O)=0.00116 54, α(P)=2.2×10-4 11, α(Q)=1.05E-5 82 | |||
(11/2)+ | 1056.2 4 | (M1+E2) | 0.038 | α=0.038 23, α(K)=0.029 19, α(L)=0.0065 35, α(M)=0.00160 83, α(N)=4.4×10-4 23, α(O)=1.16E-4 61, α(P)=2.2E-5 12, α(Q)=1.20E-6 76 | |||
(11/2)+ | 1124.9 2 | (M1+E2) | 0.032 | α=0.032 19, α(K)=0.025 16, α(L)=0.0055 29, α(M)=0.00135 69, α(N)=3.8×10-4 19, α(O)=9.8E-5 51, α(P)=1.89E-5 99, α(Q)=1.02E-6 63 | |||
(11/2)+ | 1183.0 2 | (M1+E2) | 0.028 | α=0.028 17, α(K)=0.022 13, α(L)=0.0048 25, α(M)=0.00119 60, α(N)=3.3×10-4 17, α(O)=8.6E-5 44, α(P)=1.65E-5 86, α(Q)=9.0E-7 54 | |||
(11/2)+ | 1230.6 2 | E2 | 0.01111 | α=0.01111, α(K)=0.00823 12, α(L)=0.00214 3, α(M)=0.000539 8, α(N)=0.0001502 21, α(O)=3.89×10-5 6, α(P)=7.29E-6 11, α(Q)=3.34E-7 5 | |||
1264.94 | (11/2)+ | 307.4 1 | (M1+E2) | 1.01 | α=1.01 74, α(K)=0.72 65, α(L)=0.214 77, α(M)=0.055 17, α(N)=0.0153 46, α(O)=0.0040 13, α(P)=7.3×10-4 28, α(Q)=3.2E-5 26 | ||
(11/2)+ | 375.8 1 | M1 | 1.005 | α=1.005, α(K)=0.783 11, α(L)=0.1661 24, α(M)=0.0408 6, α(N)=0.01136 16, α(O)=0.00297 5, α(P)=0.000575 8, α(Q)=3.28×10-5 5 | |||
(11/2)+ | 487.1 2 | (M1+E2) | 0.28 | α=0.28 21, α(K)=0.21 18, α(L)=0.054 28, α(M)=0.0136 64, α(N)=0.0038 18, α(O)=9.8×10-4 47, α(P)=1.86E-4 96, α(Q)=9.1E-6 70 | |||
(11/2)+ | 1151.0 2 | (M1+E2) | 0.030 | α=0.030 18, α(K)=0.023 15, α(L)=0.0052 27, α(M)=0.00127 65, α(N)=3.5×10-4 18, α(O)=9.3E-5 47, α(P)=1.78E-5 93, α(Q)=9.6E-7 59 | |||
(11/2)+ | 1209.1 2 | (M1+E2) | 0.027 | α=0.027 16, α(K)=0.021 13, α(L)=0.0045 23, α(M)=0.00112 56, α(N)=3.1×10-4 16, α(O)=8.1E-5 41, α(P)=1.56E-5 81, α(Q)=8.5E-7 51 | |||
(11/2)+ | 1256.6 2 | E2 | 0.01069 | α=0.01069, α(K)=0.00794 12, α(L)=0.00204 3, α(M)=0.000514 8, α(N)=0.0001431 20, α(O)=3.71×10-5 6, α(P)=6.96E-6 10, α(Q)=3.21E-7 5 | |||
E(level) (keV) | Jπ(level) | T1/2(level) | E(γ) (keV) | Multipolarity | Mixing Ratio | Conversion Coefficient | Additional Data |
Additional Level Data and Comments:
E(level) | Jπ(level) | T1/2(level) | Comments |
0 | 3/2- | 33 h 1 % α = 0.5 1 % ε = 99.5 1 | CONF=|p3/2-[521] (1978Ah02) E(level): π3/2-[521]. |
8.34 | (7/2)+ | CONF=|p7/2+[633] E(level): π7/2+[633]. | |
31.70 | 5/2- | E(level): π3/2-[521]. | |
55.85 | (9/2)+ | E(level): π7/2+[633]. | |
76.1 | 7/2- | E(level): π3/2-[521]. | |
114.08 | (11/2+) | E(level): π7/2+[633]. | |
182.6 | (13/2+) | E(level): π7/2+[633]. | |
263.0 | (15/2+) | E(level): π7/2+[633]. | |
411 | (1/2-) | CONF=|p1/2-[521] E(level): π1/2-[521]. From 250Cf(α,t). | |
452 | (5/2-) | E(level): π1/2-[521]. From 250Cf(α,t). | |
461.40 | 7/2- | CONF=7/2-[514] E(level): π7/2-[514]. | |
523 | (9/2-) | E(level): π7/2-[514]. From 250Cf(α,t). | |
548 | (7/2-) | E(level): π1/2-[521]. From 250Cf(α,t). | |
548 | (9/2-) | E(level): π1/2-[521]. From 250Cf(α,t). | |
661 | (1/2+) | CONF=|p1/2+[400] E(level): From 250Cf(α,t). | |
777.94 | (9/2)+ | CONF=|p9/2+[624] E(level): π9/2+[624]. | |
889.10 | (11/2)+ | CONF=|[|p7/2+[633]~#2{++}|]11/2+ E(level): |[π7/2+[633]~#2+|]11/2+ γ-vibrational band. | |
942 | (13/2)+ | E(level): π9/2+[624]. From 250Cf(α,t). | |
957.52 | (13/2)+ | E(level): |[π7/2+[633]~#2+|]11/2+ γ-vibrational band. | |
1264.94 | (11/2)+ | Interpreted as a three-quasiparticle state, but a configuration could not be definitively assigned. See 251Fm ε decay. E(level): Interpreted as a three-quasiparticle state, but a configuration could not be definitively assigned. See 251Fm ε decay. |
E(level) | E(gamma) | Comments |
461.40 | 405.55 | E(γ): Weighted average of 405.6 1 keV (1978Ah02), 405.5 3 keV (2000Ah02), and 405.2 3 keV (2005He27). | 453.06 | E(γ): Weighted average of 453.1 1 keV (1978Ah02), 453.0 3 keV (2000Ah02), and 452.8 3 keV (2005He27). |