ADOPTED LEVELS, GAMMAS for 100Nb

Authors: Balraj Singh and Jun Chen |  Citation: Nucl. Data Sheets 172, 1 (2021) |  Cutoff date: 31-Jan-2021 

 Full ENSDF file | Adopted Levels (PDF version) 


Q(β-)=6396 keV 8S(n)= 5533 keV 14S(p)= 9466 keV 13Q(α)= -3886 keV 10
Reference: 2017WA10

References:
  A  100Zr β- decay (7.1 S)  B  100Nb IT decay (12.4 μs)
  C  252Cf SF decay  D  100Mo(t,3He)

General Comments:

Mass measurement by Penning-trap method: Mass excess (g.s.)=-79802 20; mass excess (2.99S isomer)= -79488 10 (2007Ri01,2007Ha32,2006Jo14)

In (t,3He) (1979Aj03), many states are suggested by the observation of 23 groups, several of which are unresolved structures. Measured Q value=-6690 30 for the energy group labeled as ’0’, and assigned to the g.s. by 1979Aj03. Based on mass values in 2017Wa10, this Q value agrees better with the first level populated in (t,3He) identified with the 2.99S, (5+) isomer, whose energy is measured as 314 23 (2007Ri01,2007Ha32).

α 0.3-μs isomer is indicated by x(t) measurements (1970Gr38,1972ClZN) of fission fragments from 235U(n,F) (1970Gr38) and 252Cf(SF) (1972ClZN), but the mass assignment is not certain. 1970Gr38 assign this isomer to α=100, whereas 1972ClZN assign it to α=102

α 3-min activity reported by 1960Or02 and 1971Ca18 from 235U fission and by 1966Gu05 from 100Mo(n,p) reaction most likely corresponds to 99Nb β- decay (T1/2=2.6-min) and not to 100Nb. No such activity has been seen in any of the later studies on the decay of 100Nb

α 12-min activity assigned to 100Nb by 1961Ta08 from 100Mo(n,p) reaction has not been confirmed in any other 100Nb study. This activity probably corresponds to the decay of 101Mo (T1/2=14.6 min) formed by neutron capture in 100Mo

The following transitions were tentatively assigned to 100Nb from a study of prompt conversion electrons from 235U(n,F) by 1973Kh05: 84.0, 119.1, 126.4, 159.0, 172.0 and 212.0. None of these were assigned to levels in 100Nb

Theory references: consult the NSR database (www.nndc.bnl.gov/nsr/) for six primary references dealing with decay half-lives, β shape factors, and other beta-decay characteristics.

2000Lh01: theoretical calculation of level energies and spin-parities of 100Nb using the Interacting Boson-Fermion-Fermion model

Q-value: S(2n)=12415 9, S(2p)=22081 11 (2017Wa10)










E(level)
(keV)		XREFJπ(level) T1/2(level)E(γ)
(keV)		I(γ)M(γ)Final Levels
       0.0A C  1+ 1.4 s 2 
% β- = 100
     
      67.4 8   C  (2+)      67.4
  100

       0.0
1+
     159.1 8   C  (3+)      91.6
  159.1
  100
   10.8


      67.4
       0.0
(2+)
1+
     261.3 10   C  (4+)     102.1
  194.0
  100
    5.3


     159.1
      67.4
(3+)
(2+)
     314 23  B D (5)+ 2.99 s 11 
% β- = 100
     
     348 23  B   (4-,5-,6-) 0.41 µs 6 
% IT = 100
   34.3
  100
(E1)
     314
(5)+
     368.2 11   C  (5+)     106.9
  209.1
  100
   12.9


     261.3
     159.1
(4+)
(3+)
     400.52 6 A    1+ 90 ps 30    400.50 6 
  100
[M1]
       0.0
1+
     471.39 7 A    (1+)     471.48 9 
  100

       0.0
1+
     492.6 15   C      124.4
  100

     368.2
(5+)
     498.08 25 A    (0:3+)     498.08 25 
  100

       0.0
1+
     504.30 5 A    1+      33.01 10 
  103.73 10 
  504.29 5 
    0.88 16 
    2.6 4 
  100 13 
(M1)
[M1]

     471.39
     400.52
       0.0
(1+)
1+
1+
     521 23  B   (5-,6-,7-) 207 ps 14    173.3 2 
  100
M1
     348
(4-,5-,6-)
     542.4 12   C  (6+)     174.1
  281.2
  100
   18.2


     368.2
     261.3
(5+)
(4+)
     653.92 12 A    (0:3+)     253.4 1 
  100

     400.52
1+
     703.72 11 A    (0:3+)     303.2 1 
  703.7 4 
   55 8 
  100 19 


     400.52
       0.0
1+
1+
     706 23  B   (6-)     185.4 2 
  358.6 2 
  392.3 2 
  100
   88
   60
M1


     521
     348
     314
(5-,6-,7-)
(4-,5-,6-)
(5)+
     734 23  B   (8-) 12.4 µs 3 
% IT = 100
   28
  100
(E2)
     706
(6-)
E(level)
(keV)		XREFJπ(level) T1/2(level)E(γ)
(keV)		I(γ)M(γ)Final Levels
     771.9 13   C  (7+)     229.7
  403.6
  100
   26


     542.4
     368.2
(6+)
(5+)
     835.7 18   C      343.1
  100

     492.6

    1058.8 14   C  (8+)     286.9
  516.4
  100
   27


     771.9
     542.4
(7+)
(6+)
    1235.3 18   C      742.6
  100

     492.6

    1525.9 21   C      290.6
  100

    1235.3

     0+X   D        
    25+X 10    D        
   131+X 10    D        
   210+X 15 ?   D        
   348+X 15    D        
   410+X 15    D        
   450+X 20    D        
   520+X 20    D        
   565+X 10    D        
   595+X 20 ?   D        
   680+X 20    D        
   720+X 20 ?   D        
   784+X 20    D        
   820+X 20    D        
   865+X 20    D        
   893+X 20    D        
   945+X 20    D        
  1040+X 20    D        
  1075+X 20    D        
  1136+X 20    D        
  1180+X 25    D        
  1260+X 30    D        
  1300+X 30    D        

E(level): From least-squares fit to Eγ data for levels with γ-ray emission. Others are from (t,3He)

M(γ): From ce data in 100Nb IT decay, unless otherwise noted

Back to top

Band Transitions:

E(level)
(keV)		Jπ(level) T1/2(level)E(γ)I(γ)M(γ)Final Levels
Band 1 - Kπ=1+, πg9/2~#νg7/2,α=0.
      67.4 8  (2+)        
     261.3 10  (4+)     102.1
  194.0
  100
    5.3


     159.1
      67.4
(3+)
(2+)
     542.4 12  (6+)     174.1
  281.2
  100
   18.2


     368.2
     261.3
(5+)
(4+)
    1058.8 14  (8+)     286.9
  516.4
  100
   27


     771.9
     542.4
(7+)
(6+)
E(level)
(keV)		Jπ(level) T1/2(level)E(γ)I(γ)M(γ)Final Levels
Band 2 - Kπ=1+ πg9/2~#νg7/2,α=1.
     159.1 8  (3+)        
     368.2 11  (5+)     106.9
  209.1
  100
   12.9


     261.3
     159.1
(4+)
(3+)
     771.9 13  (7+)     229.7
  403.6
  100
   26


     542.4
     368.2
(6+)
(5+)

Back to top

Additional Gamma Data:













E(level)
(keV)		Jπ(level)T1/2(level)E(γ)
(keV)		MultipolarityConversion
Coefficient		Additional Data
     348 (4-,5-,6-) 0.41 µs 6 
% IT = 100
   34.3(E1)2.55B(E1)(W.u.)=5.3E-6 +12-9, α=2.55
     400.52 1+ 90 ps 30    400.50 6 [M1]B(M1)(W.u.)=0.0038 +19-10
     504.30 1+      33.01 10 (M1)5.46α=5.46
1+     103.73 10 [M1]0.204α=0.204
     521 (5-,6-,7-) 207 ps 14    173.3 2 M10.0505B(M1)(W.u.)=0.0195 13, α=0.0505
     706 (6-)     185.4 2 M10.0422α=0.0422
     734 (8-) 12.4 µs 3 
% IT = 100
   28(E2)110B(E2)(W.u.)=0.87 16, α=110

Back to top

Additional Level Data and Comments:

E(level)Jπ(level)T1/2(level)Comments
       0.01+ 1.4 s 2 
% β- = 100
Probable configuration=πg9/2νg7/2.
      67.4(2+)   E(level): Kπ=1+, πg9/2~#νg7/2,α=0.
Jπ(level): Proposed in 252Cf SF decay based on band structure.
     159.1(3+)   E(level): Kπ=1+ πg9/2~#νg7/2,α=1.
Jπ(level): Proposed in 252Cf SF decay based on band structure.
     261.3(4+)   E(level): Kπ=1+, πg9/2~#νg7/2,α=0.
Jπ(level): Proposed in 252Cf SF decay based on band structure.
     314(5)+ 2.99 s 11 
% β- = 100
XREF: d(?).
     368.2(5+)   E(level): Kπ=1+ πg9/2~#νg7/2,α=1.
Jπ(level): Proposed in 252Cf SF decay based on band structure.
     498.08(0:3+)   Jπ(level): 2+,3+ less likely from log ft=6.0-6.8 from 0+, but β feeding is quite weak which could be affected by weak unobserved γ-ray feeding from higher levels.
     542.4(6+)   E(level): Kπ=1+, πg9/2~#νg7/2,α=0.
Jπ(level): Proposed in 252Cf SF decay based on band structure.
     653.92(0:3+)   Jπ(level): 2+,3+ less likely from log ft=6.0-6.8 from 0+, but β feeding is quite weak which could be affected by weak unobserved γ-ray feeding from higher levels.
     703.72(0:3+)   Jπ(level): 2+,3+ less likely from log ft=6.0-6.8 from 0+, but β feeding is quite weak which could be affected by weak unobserved γ-ray feeding from higher levels.
     771.9(7+)   E(level): Kπ=1+ πg9/2~#νg7/2,α=1.
Jπ(level): Proposed in 252Cf SF decay based on band structure.
    1058.8(8+)   E(level): Kπ=1+, πg9/2~#νg7/2,α=0.
Jπ(level): Proposed in 252Cf SF decay based on band structure.
   450+X   E(level): Unresolved structure.
   520+X   E(level): Unresolved structure.
   595+X   E(level): Unresolved structure.
   865+X   E(level): Unresolved structure.
   945+X   E(level): Unresolved structure.
  1040+X   E(level): Unresolved structure.
  1075+X   E(level): Unresolved structure.

Back to top

Additional Gamma Comments:

E(level)E(gamma)Comments
     348      34.3M(γ): proposed by 1999Ge01 from ce spectrum and also based on the 28γ(E2)-185γ(M1)-173γ(M1) cascade from 735,(8-) level. But M1 from α(K)exp=4.7 5 in 1986LhZX
     504.30      33.01M(γ): from α(K)exp=3.1 8 (2007Ri01) in 100Zr β- decay

Back to top