ADOPTED LEVELS, GAMMAS for 251No

Authors: E. Browne, J. K. Tuli |  Citation: Nucl. Data Sheets 114, 1041 (2013) |  Cutoff date: 1-Jan-2012 

 Full ENSDF file | Adopted Levels (PDF version) 


Q(β-)=-4878 keV SYS(n)= 6784 keV SYS(p)= 3070 keV SYQ(α)= 8752 keV 4
Reference: 2012WA38

References:
  A  255Rf α decay (1.68 S)  B  206Pb(48Ca,3nγ)

General Comments:

Favored α decay calculated: 1993Bu09

Fission barrier, calculations: 1985Cw01, 1974Ba87, 1973Ba19

Fission half-life, calculations: 1978Po09

Ground state properties, calculations: 1997Mo25, 1995Mo29

Level energies calculated: 2011Ad15, 2011Ha06, 2010Ad17, 2006Sh19, 2005Pa73.

Calculated half-life: 2012Po01, 2011He12, 2010Si27, 2009Do22, 2009Sa25, 2008Do12, 2008Ro06, 2005Zh24.

Cross section calculations: 2006Fe05, 2005Zu02

Cross sections measured: 2003Be18, 2001Og08

1994Cw02 calculated the following single-particle levels: g.s., 7/2[624]; 50, 9/2[734]; 110, 5/2[622]; 440, 1/2[633]; 520, 7/2[743]. See also 2006Sh19 and 2005Pa73.

Assignment (production and identification of 251No):

1967Gh01: 244Cm(12C,5n) excitation function, half-life

2006He27, 2004He28, 2001He35: 251No isotope produced in 206Pb(48Ca,3n) reaction at E=4.80 MeV/nucleon; and from α decay of 255Rf. Reaction products were separated from the primary beam by the SHIP velocity filter and implanted into a position-sensitive 16-strip PIPS detector.

Q-value: Δ(Q(β-))=319, Δ(S(n))=231, Δ(S(p))=322 (syst,2012Wa38)

Q-value: Q(εp)=1488 115 (syst,2012Wa38)

Q-value: Q(α). Other: 8749 16 (2006He27)










E(level)
(keV)
XREFJπ(level) T1/2(level)E(γ)
(keV)
I(γ)M(γ)Final Levels
     0.0AB (7/2+) 0.80 s 1 
% ε = ?
% α = 91 +9-22
% SF < 0.3
     
    60.7 7 AB (9/2+)      60.7S
 

     0.0
(7/2+)
   106 6  B (1/2+) 1.02 s 3 
% α ≈ 100
     
   203.6 2 AB (9/2-)     143.3 2 
  203.6 2 
  100 12 
   96 12 
(E1)
E1
    60.7
     0.0
(9/2+)
(7/2+)
   917.2 6 ? B (7/2+)     713.6 5 ?
 

   203.6
(9/2-)
  1699.7 8 ? B     782.5 6 ?
 

   917.2
(7/2+)
  1699.7+X? B ≈ 2 µs     X?
 

  1699.7

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Band Transitions:

E(level)
(keV)
Jπ(level) T1/2(level)E(γ)I(γ)M(γ)Final Levels
Band 1 - 7/2[624] band
     0.0 (7/2+) 0.80 s 1 
% ε = ?
% α = 91 +9-22
% SF < 0.3
     
    60.7 7  (9/2+)      60.7S
 

     0.0
(7/2+)

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Additional Gamma Data:













E(level)
(keV)
Jπ(level)T1/2(level)E(γ)
(keV)
MultipolarityConversion
Coefficient
Additional Data
   203.6 (9/2-)     143.3 2 (E1)0.0669α=0.0669, α(L)=0.0499 8, α(M)=0.01248 18, α(N)=0.00348 5, α(O)=0.000905 13, α(P)=0.0001546 23, α(Q)=5.14×10-6 8, α(N+)=0.00455 7
(9/2-)     203.6 2 E10.1143α=0.1143, α(K)=0.0857 13, α(L)=0.0213 3, α(M)=0.00530 8, α(N)=0.001482 21, α(O)=0.000388 6, α(P)=6.84×10-5 10, α(Q)=2.52E-6 4, α(N+)=0.00194 3

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Additional Level Data and Comments:

E(level)Jπ(level)T1/2(level)Comments
     0.0(7/2+) 0.80 s 1 
% ε = ?
% α = 91 +9-22
% SF < 0.3
%α=91 +9-22, %SF<0.3 (2001He35), %ε+β+ is expected to be small. %α is from total number of 255Rf α decays and the number of α-α correlations in α-decay chain: 255Rf - 251No- 247Fm. Others: only α decay observed (1967Gh01). Calculated T1/2: T1/2(ε+β+)≈6 s, T1/2(α)≈19 s (1997Mo25); T1/2(α)≈0.6 s (1990Ha26); T1/2(SF)≈0.01 s (1985Lo17); T1/2(SF)|>10 s (2000Ho27, evaluation).
E(level): 7/2[624] band.
    60.7(9/2+)   E(level): 7/2[624] band.
   106(1/2+) 1.02 s 3 
% α ≈ 100
Isomer produced by 206Pb(48Ca,3n), E=4.80 MeV/α (2006He27,2004He28). Reaction products were separated from the primary beam by the SHIP velocity filter and implanted into a position-sensitive 16-strip PIPS detector.
E(level): Isomer produced by 206Pb(48Ca,3n), E=4.80 MeV/α (2006He27,2004He28). Reaction products were separated from the primary beam by the SHIP velocity filter and implanted into a position-sensitive 16-strip PIPS detector.
   203.6(9/2-)   Possible configuration=9/2[734] (2006He27).
   917.2(7/2+)   Possible configuration=7/2[613] (2006He27).

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Additional Gamma Comments:

E(level)E(gamma)Comments
   203.6   143.3M(γ): from α(L)exp+α(M)exp<0.25 (2006He27) in 255Rf α decay
   203.6M(γ): from α(K)exp<0.088, α(L)exp+α(M)exp<0.1 (2006He27) in 255Rf α decay
   917.2   713.6E(γ): The ordering of the 782.5-713.6 cascade is not known.
  1699.7   782.5E(γ): The ordering of the 782.5-713.6 cascade is not known.
  1699.7+X     XE(γ): expected to be a highly-converted transition

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