ADOPTED LEVELS, GAMMAS for 166Re

Author: Coral M. Baglin |  Citation: Nucl. Data Sheets 109, 1103 (2008) |  Cutoff date: 1-Mar-2008 

 Full ENSDF file | Adopted Levels (PDF version) 


Q(β-)=-6.46×103 keV 8S(n)= 9.32×103 keV 8S(p)= 3.2×102 keV 8Q(α)= 5.46×103 keV 5
Reference: 2012WA38

References:
  A  170Ir α decay (0.87 S)  B  170Ir α decay (811 MS)

General Comments:

Assignment: 93Nb(84Kr,α7n), 89Y(84Kr,7N), E=5.1 to 5.5 MeV/u and 5.8 to 6.4 MeV/u, excit (1978Sc26); 141Pr(32S,pxn), E=204 MeV, excit (1992Me10).

Q-value: Note: Current evaluation has used the following Q record

Q-value: Uncertainty in Q(β-), S(n), S(p) and Q(α) is 90, 90, 90 and 70, respectively (2003Au03).









E(level)
(keV)
XREFJπ(level) T1/2(level)E(γ)
(keV)
M(γ)Final Levels
      0A  2.25 s 21 
% ε > 76
% α < 24
    
      0.0+X B       
      0.0+YA  (3-)       
   53+X B      53
(E1)
      0.0+X

   65+X B      65S
[M1]
      0.0+X

   75+X B      75
(M1)
      0.0+X

  122+X B      47S
   69
  122

[M1]
(E1)
   75+X
   53+X
      0.0+X



  175+X B      53?
  110
  175
[M1,E2]
(E1)
(E1)
  122+X
   65+X
      0.0+X



E(level): From Eγ, except as noted.

E(γ): From 170Ir α decay (811 ms); uncertainties unstated by authors.

M(γ): Very tentative values from arguments based on γ and K| x ray intensities in α-γ coin spectra in 170Ir α decay (811 ms), except as noted.

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Additional Gamma Data:













E(level)
(keV)
Jπ(level)T1/2(level)E(γ)
(keV)
MultipolarityConversion
Coefficient
Additional Data
   53+X      53(E1)0.410α=0.410
   65+X      65[M1]3.12α=3.12
   75+X      75(M1)11.75α=11.75
  122+X      69[M1]2.62α=2.62
    122(E1)0.229α=0.229
  175+X      53[M1,E2]40α=40 40
    110(E1)0.300α=0.300
    175(E1)0.0906α=0.0906

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Additional Level Data and Comments:

E(level)Jπ(level)T1/2(level)Comments
      0 2.25 s 21 
% ε > 76
% α < 24
Jπ(level): The lowest-energy orbitals available for the 75th proton are probably 1/2[411] (d3/2) and 9/2[514] (h11/2) based on possible Jπ=(1/2+) and (9/2-) for the g.s. of 165Re and 167Re, respectively; the lowest-energy neutron orbital available to the 91St neutron is probably 5/2[523] (f7/2) based on Jπ=(5/2-) for the g.s. of the isotone 165W (1995Hi02). If the deformation is large enough for the Gallagher-Moszkowski rule to Be valid, low-lying 3- and 7+ states might Be expected, but no low-lying isomeric excited state has been identified in 166Re as yet. ε decay to 166W indicates an intensity imbalance at each of the 2+, 4+ and 6+ levels observed so far; this is probably the result of a very incomplete decay scheme, so this provides no useful indication of Jπ(g.s.) for 166Re. The possibility that the 0+x or the 0+y level is, in fact, the g.s. cannot Be ruled out.
T1/2(level): Weighted average of 2.23 s 27 from 252γ(t) and 2.28 s 34 from 424γ(t) in ε decay (1992Me10). Other data: 2.2 s 4 (1978Sc26, for Eα=5495 10); 1.9 s 11 (1992Me10, for Eα=5501 13; however, α=165 contribution cannot Be ruled out); the Eα=5506 10, 2.4 s 6 line assigned by 1981Ho10 to 165Re has T1/2 and Eα consistent with those for 166Re (to which 1978Sc26 assign their 5495 10 line and 1982De11 assign their 5527 4 line) but 1996Pa01 confirm its assignment to 165Re. T1/2=2.8 s 3 (1984Sc06, for Eα=5372 10) was assigned by those authors to 166Re, but neither 1992Me10 nor 1996Pa01 see this line so the evaluator presumes it to have been misassigned. Note that the assignment of this T1/2 to the 166Re g.s. here is at variance with the assumption in 2003Wa32 that the observed 166Re α decay takes place from an excited state, unless both states have comparable T1/2.
   53+X   π probably opposite to π(0+x) level based on (E1) 53γ to 0.0+x level.
E(level): π probably opposite to π(0+x) level based on (E1) 53γ to 0.0+x level.
   65+X   π probably same as π(0+x) level based on (E1) 110γ from 175+x level.
E(level): π probably same as π(0+x) level based on (E1) 110γ from 175+x level.
   75+X   π probably same as π(0+x) level based on (M1) 75γ to 0.0+x level.
E(level): π probably same as π(0+x) level based on (M1) 75γ to 0.0+x level.
  122+X   π probably opposite to π(0+x) level based on (E1) 122γ to 0.0+x level.
E(level): π probably opposite to π(0+x) level based on (E1) 122γ to 0.0+x level.
  175+X   π probably opposite to π(0+x) level based on (E1) 175γ to 0.0+x level.
E(level): π probably opposite to π(0+x) level based on (E1) 175γ to 0.0+x level.

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Additional Gamma Comments:

E(level)E(gamma)Comments
   53+X     53E(γ): Multiply placed
   75+X     75M(γ): suggested in 170Ir α decay (811 ms) based on 6053α-γ coin spectrum which includes significant I(K| x ray) attributed to internal conversion of the 75γ; analogous to authors’ observations for known M1 92γ from 171Re α decay.
  122+X     47E(γ): highly tentative; however, observation of 2007α-75γ coin (2007Ha45) suggests the existence of a transition connecting the 122+x and 75+x levels and such a transition may Be too highly converted to Be seen in α-γ coincidence spectrum. Level scheme implies Δπ=(yes), suggesting a multipolarity of M2 or higher.
    122M(γ): since I(75γ)/I(Kα| x ray) in 170Ir α decay (811 ms) is approximately the same in spectra gated by the 6053α and by the 6007α, 2007Ha45 conclude that the 122γ is probably E1 since it provides no significant contribution to K| x ray peak’s intensity via internal conversion.
  175+X     53E(γ): Multiply placed
M(γ): assumed, based on level scheme; however, I(53γ)/I(122γ) in 170Ir α decay (811 ms) is approximately the same in the spectra gated by 5951α or by the 6007α (2007Ha45). Authors favor M1 multipolarity for this component and E1 for the other.
    110M(γ): based on an argument similar to that used by 2007Ha45 to assign multipolarity to 122γ.
    175M(γ): based on an argument similar to that used by 2007Ha45 to assign multipolarity to 122γ.

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