ADOPTED LEVELS, GAMMAS for 223Ac

Author: E. Browne |  Citation: Nucl. Data Sheets 93, 846 (2001) |  Cutoff date: 1-May-2001 

 Full ENSDF file | Adopted Levels (PDF version) 


Q(β-)=-1559 keV 12S(n)= 6866 keV 9S(p)= 3784 keV 9Q(α)= 6783.2 keV 10
Reference: 2012WA38

References:
  A  227Pa α decay 

General Comments:

Levels: The level structure presents the characteristic parity doublet bands and has been interpreted in terms of a nucleus with both quadrupole and octupole stable deformations (1988Le13,1989Ah05,1990Sh16,1990Sh15). α 5/2[523] configuration was assigned to the ground state of 223Ac, and a 3/2[532] configuration is expected to lie close to the ground state (1988Le13). Favored α decay from 227Pa (5/2-) populates the g.s. of 223Ac (HF=2.5) and the 50.7 (5/2-) level (HF=5.1) through the Coriolis mixing between these states. No direct α decay from 227Pa (5/2-) to levels with Jπ=3/2- has been observed because such levels are not be mixed with the favored (Jπ=5/2-) ground state (1988Le13). Level parities assigned by 1990Sh16 and 1990Sh15 are opposite to those given by 1989Ah05. These quantities are essentially determined by the parity of the 223Ac ground state, which has been adopted as odd in this evaluation.

Levels: Because of the small quadrupole, and the suggested octupole deformations in this region, nuclear states are no longer characterized by single Nilsson orbitals. These are, however, used here more as labels rather than to accurately describe the nature of those states.

Q-value: Note: Current evaluation has used the following Q record $ -1555 126863 93783 8 6783.1 9 1995Au04










E(level)
(keV)
XREFJπ(level) T1/2(level)E(γ)
(keV)
I(γ)M(γ)Final Levels
    0.0A (5/2-) 2.10 m 5 
% α = 99
% ε = 1
     
   12.5 2 ?A (3/2-)        
   42.4 1 A (7/2-) ≤ 0.25 ns    42.4 1 
   100
M1+E2
    0.0
(5/2-)
   50.7 1 A (5/2-) ≤ 0.25 ns     8.0S
   50.7 1 
     6
   100
[M1]
M1+E2
   42.4
    0.0
(7/2-)
(5/2-)
   64.62 4 A (5/2+) ≤ 0.25 ns    22.3 1 
   64.62 5 
     2.1 6 
   100
E1
E1
   42.4
    0.0
(7/2-)
(5/2-)
   90.7 1 A (9/2-) ≤ 0.25 ns    48.3 1 
   100
M1
   42.4
(7/2-)
  107.2 2 A (7/2-) ≤ 0.25 ns    56.6 2 
  107.0 5 
   ≈80
  ≈100

M1
   50.7
    0.0
(5/2-)
(5/2-)
  110.06 4 A (7/2+) ≤ 0.25 ns    45.6 2 
   59.5 2 
   67.6 1 
  110.05 5 
    ≈2.5
     8.4 20 
    34 4 
   100 7 
(M1)
E1
E1
E1
   64.62
   50.7
   42.4
    0.0
(5/2+)
(5/2-)
(7/2-)
(5/2-)
  130.7 1 A (7/2+)      80.0 1 ?
  130.7 1 ?
    56 9 
   100 23 
E1
E1
   50.7
    0.0
(5/2-)
(5/2-)
  141 5 A (11/2-)        
  167.5 1 A (9/2+) ≤ 0.25 ns    57.5
   77.0 2 
  125.1 1 
 
    13 7 
   100 15 

(E1)
E1
  110.06
   90.7
   42.4
(7/2+)
(9/2-)
(7/2-)

E(level): From 227Pa α decay.

Jπ(level): Parity doublet rotational band assignments are from 1990Sh16, 1990Sh15, 1989Ah05, and 1990Ja11. Spin and parity assignments are based on rotational band structure and γ-ray multipolarities. Specific arguments are given with individual levels.

T1/2(level): From 227Pa α decay (1989Ah05).

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Band Transitions:

E(level)
(keV)
Jπ(level) T1/2(level)E(γ)I(γ)M(γ)Final Levels
Band 1 - 5/2(523) PARITY DOUBLET ROTATIONAL band.
    0.0 (5/2-) 2.10 m 5 
% α = 99
% ε = 1
     
   42.4 1  (7/2-) ≤ 0.25 ns      
   90.7 1  (9/2-) ≤ 0.25 ns    48.3 1 
   100
M1
   42.4
(7/2-)
  141 5  (11/2-)     
E(level)
(keV)
Jπ(level) T1/2(level)E(γ)I(γ)M(γ)Final Levels
Band 2 - 5/2(642) PARITY DOUBLET ROTATIONAL band.
   64.62 4  (5/2+) ≤ 0.25 ns      
  110.06 4  (7/2+) ≤ 0.25 ns      
  167.5 1  (9/2+) ≤ 0.25 ns    57.5
   77.0 2 
  125.1 1 
 
    13 7 
   100 15 

(E1)
E1
  110.06
   90.7
   42.4
(7/2+)
(9/2-)
(7/2-)
E(level)
(keV)
Jπ(level) T1/2(level)E(γ)I(γ)M(γ)Final Levels
Band 3 - 3/2(532) PARITY DOUBLET ROTATIONAL band.
   12.5 2  (3/2-)        
   50.7 1  (5/2-) ≤ 0.25 ns      
  107.2 2  (7/2-) ≤ 0.25 ns    56.6 2 
  107.0 5 
   ≈80
  ≈100

M1
   50.7
    0.0
(5/2-)
(5/2-)
E(level)
(keV)
Jπ(level) T1/2(level)E(γ)I(γ)M(γ)Final Levels
Band 4 - 3/2(651) PARITY DOUBLET ROTATIONAL band.
  130.7 1  (7/2+)        

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Additional Gamma Data:















E(level)
(keV)
Jπ(level)T1/2(level)E(γ)
(keV)
MultipolarityMixing
Ratio
Conversion
Coefficient
Additional Data
   42.4 (7/2-) ≤ 0.25 ns    42.4 1 M1+E20.63 1214α=214
   50.7 (5/2-) ≤ 0.25 ns     8.0[M1] 1542α=1542
(5/2-) ≤ 0.25 ns    50.7 1 M1+E20.26 141.9α=41.9 11
   64.62 (5/2+) ≤ 0.25 ns    22.3 1 E1 6.17α=6.17
(5/2+) ≤ 0.25 ns    64.62 5 E1 0.369α=0.369
   90.7 (9/2-) ≤ 0.25 ns    48.3 1 M1 30.3α=30.3
  107.2 (7/2-) ≤ 0.25 ns   107.0 5 M1 7.17α=7.17
  110.06 (7/2+) ≤ 0.25 ns    45.6 2 (M1) 36.0α=36.0
(7/2+) ≤ 0.25 ns    59.5 2 E1 0.459α=0.459
(7/2+) ≤ 0.25 ns    67.6 1 E1 0.327α=0.327
(7/2+) ≤ 0.25 ns   110.05 5 E1 0.393α=0.393
  130.7 (7/2+)      80.0 1 E1 0.209α=0.209
(7/2+)     130.7 1 E1 0.259α=0.259
  167.5 (9/2+) ≤ 0.25 ns    77.0 2 (E1) 0.231α=0.231
(9/2+) ≤ 0.25 ns   125.1 1 E1 0.288α=0.288

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Additional Level Data and Comments:

E(level)Jπ(level)T1/2(level)Comments
    0.0(5/2-) 2.10 m 5 
% α = 99
% ε = 1
%α: from 1951Me10.
E(level): %α: from 1951Me10. 5/2(523) PARITY DOUBLET ROTATIONAL band.
   12.5(3/2-)   E(level): 3/2(532) PARITY DOUBLET ROTATIONAL band.
   42.4(7/2-) ≤ 0.25 ns E(level): 5/2(523) PARITY DOUBLET ROTATIONAL band.
   50.7(5/2-) ≤ 0.25 ns E(level): 3/2(532) PARITY DOUBLET ROTATIONAL band.
   64.62(5/2+) ≤ 0.25 ns E(level): 5/2(642) PARITY DOUBLET ROTATIONAL band.
   90.7(9/2-) ≤ 0.25 ns E(level): 5/2(523) PARITY DOUBLET ROTATIONAL band.
  107.2(7/2-) ≤ 0.25 ns E(level): 3/2(532) PARITY DOUBLET ROTATIONAL band.
  110.06(7/2+) ≤ 0.25 ns E(level): 5/2(642) PARITY DOUBLET ROTATIONAL band.
  130.7(7/2+)   E(level): 3/2(651) PARITY DOUBLET ROTATIONAL band.
  141(11/2-)   E(level): 5/2(523) PARITY DOUBLET ROTATIONAL band.
  167.5(9/2+) ≤ 0.25 ns E(level): 5/2(642) PARITY DOUBLET ROTATIONAL band.

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