ADOPTED LEVELS, GAMMAS for 252Cf

Authors: A.M. Mattera, S. Zhu, A.B. Hayes, E.A. Mccutchan  Citation: Nucl. Data Sheets 172, 543 (2021)  Cutoff date: 1-Jan-2021

Full ENSDF file

Q(β-)=-1.26E+3 keV 5S(n)= 6172 keV 4S(p)= 6482 keV 11Q(α)= 6216.95 keV 4
Reference: 2017WA10

References:
  A  256Fm α decay  B  252Es ε decay
  C  Coulomb Excitation  D  CF(18O,xγ)

E(level)
(keV)		XREFJπ(level) T1/2(level)E(γ)
(keV)		I(γ)M(γ)Final level
    0.0ABCD 0+ 2.647 y 3 
% α = 96.898 3
% SF = 3.102 3
     
   45.72 5 ABCD 2+ 92 ps 6     45.72 5 
  100
E2
    0.0
0+
  151.73 6  B D 4+     106.02 5 
  100
E2
   45.72
2+
  316.23 12    D 6+     164.5 1 
  100
E2
  151.73
4+
  536.6 3    D 8+     220.4 3 
  100
E2
  316.23
6+
  804.82 7  B   (2+)     759.1 1 
  804.8 1 
  100 8 
   77 5 
[E2]
[E2]
   45.72
    0.0
2+
0+
  809.2 6    D 10+     272.6 5 
  100
E2
  536.6
8+
  830.81 7  B   (2-)     785.1 1 
  100
[E1]
   45.72
2+
  845.72 9  B   (3+)     694.0 1 
  800.0 1 
   30.9 21 
  100 7 


  151.73
   45.72
4+
2+
  867.52 7  B   (3-)     715.8 1 
  821.8 1 
  100 6 
   40 3 
[E1]
[E1]
  151.73
   45.72
4+
2+
  900.33 25  B   (4+)     748.6 3 
  854.6 4 
  100 17 
   45 10 
[E2]
[E2]
  151.73
   45.72
4+
2+
  917.03 12  B   (4-)     765.3 1 
  100
[E1]
  151.73
4+
  969.83 6  B   (3+)     102.32 5 
  139.03 5 
  165.0 1 
  818.1 1 
  924.1 1 
   13.6 9 
  100 8 
    1.04 11 
    5.4 4 
   17.4 11 
[E1]
E1
M1


  867.52
  830.81
  804.82
  151.73
   45.72
(3-)
(2-)
(2+)
4+
2+
E(level): From a least-squares fit to Eγ, by evaluators.

Additional Gamma data:

E(level)
(keV)		E(γ)
(keV)		MultipolarityAdditional Data
   45.72   45.72 5 E2B(E2)(W.u.)=349 24, α=9.2E2 5, α(L)=661 34, α(M)=188 10, α(N)=52.9 27, α(O)=13.1 7, α(P)=2.05 10, α(Q)=0.00469 21
  151.73  106.02 5 E2α=16.97 25, α(L)=12.22 18, α(M)=3.49 5, α(N)=0.981 14, α(O)=0.243 4, α(P)=0.0389 6, α(Q)=0.0001510 22
  316.23  164.5 1 E2α=2.49 11, α(K)=0.1557 22, α(L)=1.68 8, α(M)=0.478 22, α(N)=0.134 6, α(O)=0.0334 15, α(P)=0.00543 25, α(Q)=3.29E-5 11
  536.6  220.4 3 E2α=0.791 32, α(K)=0.1268 23, α(L)=0.480 22, α(M)=0.135 6, α(N)=0.0380 17, α(O)=0.0095 4, α(P)=0.00156 7, α(Q)=1.37E-5 4
  804.82  759.1 1 [E2]α=0.0265 7, α(K)=0.0177 4, α(L)=0.00648 20, α(M)=0.00169 5, α(N)=0.000470 15, α(O)=0.000120 4, α(P)=2.17E-5 7, α(Q)=7.86E-7 19
  804.8 1 [E2]α=0.0236 6, α(K)=0.01606 35, α(L)=0.00555 17, α(M)=0.00144 4, α(N)=0.000400 12, α(O)=0.0001020 31, α(P)=1.86E-5 6, α(Q)=7.01E-7 17
  809.2  272.6 5 E2α=0.373 14, α(K)=0.0950 19, α(L)=0.202 9, α(M)=0.0564 24, α(N)=0.0158 7, α(O)=0.00395 17, α(P)=0.000661 28, α(Q)=7.69E-6 23
  830.81  785.1 1 [E1]α=0.00719 16, α(K)=0.00577 13, α(L)=0.001066 25, α(M)=0.000257 6, α(N)=7.08E-5 17, α(O)=1.82E-5 4, α(P)=3.45E-6 8, α(Q)=1.88E-7 4
  867.52  715.8 1 [E1]α=0.00847 19, α(K)=0.00678 15, α(L)=0.001265 30, α(M)=0.000306 7, α(N)=8.42E-5 20, α(O)=2.17E-5 5, α(P)=4.08E-6 9, α(Q)=2.20E-7 5
  821.8 1 [E1]α=0.00664 15, α(K)=0.00534 12, α(L)=0.000981 23, α(M)=0.000237 6, α(N)=6.51E-5 15, α(O)=1.68E-5 4, α(P)=3.18E-6 7, α(Q)=1.75E-7 4
  900.33  748.6 3 [E2]α=0.0273 7, α(K)=0.0181 4, α(L)=0.00673 21, α(M)=0.00176 6, α(N)=0.000489 15, α(O)=0.000124 4, α(P)=2.26E-5 7, α(Q)=8.07E-7 20
  854.6 4 [E2]α=0.0209 5, α(K)=0.01452 32, α(L)=0.00475 14, α(M)=0.00122 4, α(N)=0.000341 10, α(O)=8.69E-5 26, α(P)=1.59E-5 5, α(Q)=6.24E-7 15
  917.03  765.3 1 [E1]α=0.00752 17, α(K)=0.00604 14, α(L)=0.001118 26, α(M)=0.000270 6, α(N)=7.43E-5 17, α(O)=1.91E-5 4, α(P)=3.61E-6 8, α(Q)=1.97E-7 4
  969.83  102.32 5 [E1]α=0.1394 20, α(L)=0.1043 15, α(M)=0.0260 4, α(N)=0.00711 10, α(O)=0.001772 25, α(P)=0.000296 4, α(Q)=1.004E-5 14
  139.03 5 E1α=0.2502 35, α(K)=0.1862 26, α(L)=0.0479 7, α(M)=0.01186 17, α(N)=0.00326 5, α(O)=0.000817 12, α(P)=0.0001406 20, α(Q)=5.25E-6 7
  165.0 1 M1α=9.89

Additional Level data and comments:

E(level)Comments
    0.0%α and %SF from weighted average of deduced %SF values from α/SF=31.56 35 (1993Pa29), 31.5 3 (1970Al23), 31.3 5 (1970Al23), 31.3 2 (1965Me02), 31 1 (1954Ma98) and measured %SF value of 3.1028 27 (2018Be29). Other α/SF measurements: T1/2(SF)=66 y 10 (1957Ea01), α/SF=36.4 (1961Se18).
E(level): Kπ=0+ g.s. band.
T1/2(level): 2.647 y 3 adopted from 1994KhZW on the analysis of the following measured half-lives: 2.646 y 4 (1965Me02), 2.621 y 6 (1969De23), 2.659 y 10 (1973Mi05), 2.638 y 7 (1974Sp02), 2.637 y 5 (1976Mo30), 2.640 y 7 (1982La25), 2.651 y 4 (1984SmZV), 2.648 y 2 (W.γ. Alberts and M. Matzke, PTB Mitteilungen 93, 315 (1983)), and 2.6503 y 31 (1985Ax02). This analysis took into account the duration and the number of measurements in each experiment by comparing them with a formulated ideal experiment. Other measured half-lives: 2.55 y 15 (1957Ea01); 2.628 y 10 (1974Sh15); 2.653 y 1 (quoted in 1992Ra08 as private communication J.R. Smith). Other evaluated half-lives: 2.645 y 8 (1986LoZT: an average of 2.638 y and 2.651 y with a quoted error sufficiently large to cover the range of uncertainty); 2.648 y 2 (1992Ra08: Rajeval method); 2.650 y 2 (1994Ka08: Modified Bayesian Method).
   45.72B(E2)=16.7 {I11} (1971Fo17)
E(level): Kπ=0+ g.s. band.
Jπ(level): E2 γ to 0+; populated from 0+ by Coulomb excitation.
T1/2(level): calculated from B(E2)|^=16.7 e2b2 11 in Coulomb excitation with α(45.72γ)=917.
  151.73E(level): Kπ=0+ g.s. band.
Jπ(level): E2 γ to 2+.
  316.23E(level): Kπ=0+ g.s. band.
Jπ(level): E2 γ to 4+.
  536.6E(level): Kπ=0+ g.s. band.
Jπ(level): E2 γ to 6+.
  804.82E(level): Kπ=2+ γ-vibrational band. Mixed with the K=3 state at.
Jπ(level): γs to 0+ and 2+, no γ to 4+; analogous to the K=2, 2+ band head of Kπ=2+ band observed in 250Cf and 254Fm.
  809.2E(level): Kπ=0+ g.s. band.
Jπ(level): E2 γ to 8+.
  830.81E(level): Kπ=2- band.
Jπ(level): no γs to 0+ or 4+; 785.1γ to 2+, analogous to the K=2,2- band head of Kπ=2- band observed in 250Cf, and consistent with its properties.
  845.72E(level): Kπ=2+ γ-vibrational band. Mixed with the K=3 state at.
Jπ(level): γs to 2+ and 4+, no γ to 0+; member of Kπ=2+ band.
  867.52E(level): Kπ=2- band.
Jπ(level): γs to 4+ and 2+, no γ to 0+; member of Kπ=2- band.
  900.33E(level): Kπ=2+ γ-vibrational band. Mixed with the K=3 state at.
Jπ(level): γs to 4+ and 2+, no γ to 0+; member of Kπ=2+ band.
  917.03E(level): Kπ=2- band.
Jπ(level): γ to 4+, no γs to 2+, 0+; member of Kπ=2- band.
  969.83the two-quasiparticle configuration of ν 1/2[620] + ν 7/2[613] was proposed by 1973Fi06. This assignment is consistent with its population in 252Es ε decay.
E(level):
Jπ(level): E1 γ to (2-); M1 γ to (2+); γs to 2+ and 4+; and no γ to 0+.

Additional Gamma comments:

E(level)E(gamma)Comments
   45.72   45.72E(γ): other: 44.0 keV 5 in Coulomb Excitation
M(γ): from α(M)exp=240, α(N+O+...)=70 with uncertainties better than 15% in 252Es ε decay
  151.73  106.02M(γ): from α(L2)exp=7.2, α(L3)exp=3.8 with uncertainties better than 15% in 252Es ε decay
  316.23  164.5E(γ): from Cf(18O,Xγ) (2010Ta10).
M(γ): Q from Iγ(in-plane)/Iγ(out-of-plane)=1.33 22 in Cf(18O,Xγ); E2 from assignment to rotational band
  536.6  220.4E(γ): from Cf(18O,Xγ) (2010Ta10).
M(γ): Q from Iγ(in-plane)/Iγ(out-of-plane)=1.1 3 in Cf(18O,Xγ); E2 from assignment to rotational band
  809.2  272.6E(γ): from Cf(18O,Xγ) (2010Ta10).
M(γ): Q from Iγ(in-plane)/Iγ(out-of-plane)=1.4 4 in Cf(18O,Xγ); E2 from assignment to rotational band
  969.83  139.03M(γ): from α(L1+L2)exp=0.03 with uncertainty better than 15% in 252Es ε decay