ADOPTED LEVELS, GAMMAS for 157Eu

Author: N. Nica |  Citation: Nucl. Data Sheets 132, 1 (2016) |  Cutoff date: 4-Dec-2015 

 Full ENSDF file | Adopted Levels (PDF version) 


Q(β-)=1365 keV 4S(n)= 7448 keV 5S(p)= 7387 keV 9Q(α)= -1236 keV 10
S(2n)= 13783 keV 5S(2p)= 17097 keV 9
Reference: 2017WA10

References:
  A  157Sm β- decay  B  158Gd(pol t,α)
  C  160Gd(p,α) 

General Comments:

Model calculations that may be of interest: bandhead energies 1990Na14.

Levels: The 160Gd(p,α) reaction has been studied (1980ShZL), and the evaluator has created a list of levels from a plot of the α spectrum, but these levels are not included here. These data suggest the existence of about six additional levels between 760 and 950 keV; otherwise, all of the (p,α) peaks can be related to adopted levels.









E(level)
(keV)		XREFJπ(level) T1/2(level)E(γ)
(keV)		I(γ)Final Levels
      0.0ABC 5/2+ 15.18 h 3 
% β- = 100
    
     76.709 6 ABC 7/2+       76.701 7 
  100
      0.0
5/2+
    177 4  B  9/2+       
    197.863 6 ABC 5/2-      121.147 7 
   197.870 8 
    8.50 16 
  100.0 3 
     76.709
      0.0
7/2+
5/2+
    263.228 14 ABC 7/2-       65.44 10 
   186.55 3 
   263.207 22 
    5.4 17 
   60 3 
  100 5 
    197.863
     76.709
      0.0
5/2-
7/2+
5/2+
   ≈296 B  (11/2+)       
    350 4  B  9/2-       
    394.334 9 ABC 3/2+      196.461 9 
   317.46 7 
   394.351 16 
  100.0 14 
    7.8 5 
   71.7 10 
    197.863
     76.709
      0.0
5/2-
7/2+
5/2+
    453.500 12 ABC 5/2+       59.168 10 
   190.273 17 
   376.70 11 
   453.47 6 
   99.5 25 
  100 3 
   26 3 
   36 10 
    394.334
    263.228
     76.709
      0.0
3/2+
7/2-
7/2+
5/2+
    457 4  B  11/2-       
    539 4  B  7/2+       
    584 4  B  (13/2-)       
    645 4  B  9/2+       
    670.419 25 A        216.95 6 
   276.05 3 
   472.65 6 
   670.46 11 
   32 4 
  100 3 
   78 5 
   51 4 
    453.500
    394.334
    197.863
      0.0
5/2+
3/2+
5/2-
5/2+
    716.31 5 A        321.78 10 
   453.1 4 
   518.46 11 
   716.40 7 
   33 4 
   39 10 
   41 4 
  100 6 
    394.334
    263.228
    197.863
      0.0
3/2+
7/2-
5/2-
5/2+
E(level)
(keV)		XREFJπ(level) T1/2(level)E(γ)
(keV)		I(γ)Final Levels
    724 4  B  (15/2-)       
    971.99 9 ABC 3/2+      518.46 11 
   577.69 12 
   92 10 
  100 15 
    453.500
    394.334
5/2+
3/2+
    988.38 10 A        534.60 20 
   594.24 17 
   988.38 13 
   13 3 
   20 3 
  100 15 
    453.500
    394.334
      0.0
5/2+
3/2+
5/2+
   1021.27 10 A        758.2 3 
   823.39 10 
   37 9 
  100 8 
    263.228
    197.863
7/2-
5/2-
   1057 4  B  1/2+       
   1073 4  B        
  ≈1098 B        
   1145 4  B  (5/2+)       
  ≈1247 B        
  ≈1300 B        
   1322 4  B  (7/2+)       
   1360.92 13 A        966.2 3 
  1163.14 14 
   36 7 
  100 8 
    394.334
    197.863
3/2+
5/2-
   1369 4  B        
   1377.32 12 A       1300.1 3 
  1377.40 12 
   46 10 
  100 8 
     76.709
      0.0
7/2+
5/2+
   1382.94 80 A        988.2 1 
  1185.65 12 
   73 32 
  100 9 
    394.334
    197.863
3/2+
5/2-
   1404 4  B        
   1418.47 18 A       1155.04 24 
  1220.82 25 
  100 19 
   89 17 
    263.228
    197.863
7/2-
5/2-
   1463.12 7 ABC     1386.35 10 
  1463.16 9 
   34.5 22 
  100 6 
     76.709
      0.0
7/2+
5/2+
   1562 4  B        
   1603 4  B        
   1635 4  B        
E(level)
(keV)		XREFJπ(level) T1/2(level)E(γ)
(keV)		I(γ)Final Levels
   1711 4  B        
   1823 4  B        
   1850 4  B        
   1945 4  B        
   2035 4  B        

E(level): The pseudolevels included in the 157Sm β- decay are not included here.

E(level): From least-squares fit to the γ energies where γ’s are present, that is, the levels populated by the β- decay of 157Sm; other values are from the (pol t,α) reaction.

Jπ(level): The Jπ and Nilsson orbital assignments are primarily based on the interpretation of (pol t,α) results in terms of the predicted Nilsson orbitals and the associated bands. Where the γ’s are observed, the decay modes support these assignments.

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Band Transitions:

E(level)
(keV)		Jπ(level) T1/2(level)E(γ)I(γ)Final Levels
Band 1 - 5/2[413] band, α=10.96
      0.0 5/2+ 15.18 h 3 
% β- = 100
    
     76.709 6  7/2+       76.701 7 
  100
      0.0
5/2+
    177 4  9/2+       
   ≈296 (11/2+)     
E(level)
(keV)		Jπ(level) T1/2(level)E(γ)I(γ)Final Levels
Band 2 - 5/2[532] band, α=9.34
    197.863 6  5/2-       
    263.228 14  7/2-       65.44 10 
   186.55 3 
   263.207 22 
    5.4 17 
   60 3 
  100 5 
    197.863
     76.709
      0.0
5/2-
7/2+
5/2+
    350 4  9/2-       
    457 4  11/2-     
    584 4  (13/2-)     
    724 4  (15/2-)       
E(level)
(keV)		Jπ(level) T1/2(level)E(γ)I(γ)Final Levels
Band 3 - 3/2[411] band, α=11.83
    394.334 9  3/2+       
    453.500 12  5/2+       59.168 10 
   190.273 17 
   376.70 11 
   453.47 6 
   99.5 25 
  100 3 
   26 3 
   36 10 
    394.334
    263.228
     76.709
      0.0
3/2+
7/2-
7/2+
5/2+
    539 4  7/2+       
    645 4  9/2+     
E(level)
(keV)		Jπ(level) T1/2(level)E(γ)I(γ)Final Levels
Band 4 - 1/2[420] band, α=14.7, a=1.0
   1057 4  1/2+       
   1145 4  (5/2+)     
   1322 4  (7/2+)       
E(level)
(keV)		Jπ(level) T1/2(level)E(γ)I(γ)Final Levels
Band 5 - 1/2[411] band
    971.99 9  3/2+       

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Additional Level Data and Comments:

E(level)Jπ(level)T1/2(level)Comments
      0.05/2+ 15.18 h 3 
% β- = 100
Q=+2.6 3, μ=+1.50 2
Δ<r2>(151,157) ≈ |l(157,151)=0.779 fm2 6 (1990Al34) given directly and |l(156,157)=0.086 9 and |l(157,158)=0.060 8 by subtraction of table entries. Uncertainties include only the statistical components.
E(level): Δ<r2>(151,157) ≈ |l(157,151)=0.779 fm2 6 (1990Al34) given directly and |l(156,157)=0.086 9 and |l(157,158)=0.060 8 by subtraction of table entries. Uncertainties include only the statistical components. 5/2[413] band, α=10.96.
     76.7097/2+   E(level): 5/2[413] band, α=10.96.
    1779/2+   E(level): 5/2[413] band, α=10.96.
    197.8635/2-   E(level): 5/2[532] band, α=9.34.
    263.2287/2-   E(level): 5/2[532] band, α=9.34.
    296(11/2+)   E(level): 5/2[413] band, α=10.96.
    3509/2-   E(level): 5/2[532] band, α=9.34.
    394.3343/2+   E(level): 3/2[411] band, α=11.83.
    453.5005/2+   E(level): 3/2[411] band, α=11.83.
    45711/2-   E(level): 5/2[532] band, α=9.34.
    5397/2+   E(level): 3/2[411] band, α=11.83.
    584(13/2-)   E(level): 5/2[532] band, α=9.34.
    6459/2+   E(level): 3/2[411] band, α=11.83.
    724(15/2-)   E(level): 5/2[532] band, α=9.34.
    971.993/2+   E(level): 1/2[411] band.
   10571/2+   E(level): 1/2[420] band, α=14.7, a=1.0.
   1145(5/2+)   Probably a doublet in (pol t,α). The 3/2+ and 5/2+ members of this band are expected to lie close together.
E(level): Probably a doublet in (pol t,α). The 3/2+ and 5/2+ members of this band are expected to lie close together. 1/2[420] band, α=14.7, a=1.0.
   1322(7/2+)   E(level): 1/2[420] band, α=14.7, a=1.0.

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