ADOPTED LEVELS, GAMMAS for 12B

Authors: J.H. Kelley, J.E. Purcell and C.G. Sheu |  Citation: Nucl. Physics A968, 71 (2017) |  Cutoff date: 1-Jan-2017 

 Full ENSDF file | Adopted Levels (PDF version) 


Q(β-)=13369.4 keV 13S(n)= 3369.6 keV 13S(p)= 14096.7 keV 13Q(α)= -10001.3 keV 13
Reference: 2017WA10

References:
  A  12Be β- decay  B  2H(14C,α)
  C  4He(8Li,α):RES  D  6Li(7Li,p)
  E  7Li(7Li,d),7Li(7Li,12B)  F  7Li(9Be,12B)
  G  9Be(t,n):RES  H  9Be(α,p)
  I  9Be(6Li,3He)  J  9Be(7Li,α)
  K  10B(t,p)  L  11B(n,γ):E=THERMAL
  M  11B(n,γ):RES  N  11B(n,n),(n,n’):RES
  O  11B(n,α)  P  11B(p,π+)
  Q  11B(d,pγ),2H(11B,p)  R  11B(7Li,6Li)
  S  12C(γ,π+)  T  12C(μ-,ν)
  U  12C(n,p)  V  12C(d,2p)
  W  12C(t,3He)  X  12C(7Li,7Be)
  Y  12C(12Be,12B),1H(12Be,12B)  Z  12C(12C,12N)
  a  12C(13C,13N)  b  13C(d,3He)
  c  14C(p,3He) 

General Comments:

Analyses of the 12B density profile have been carried out based on measurements of various reaction cross sections and momentum distributions of breakup products. See discussions in references listed below.

1988Ta10: 9Be, 12C, 27Al(12B,X) E=790 MeV/nucleon, measured interaction σ. Deduced Rmatterr.m.s.=2.39 fm 2.

1989Sa10: Cu(12B,12B), measured reaction σ for projectile 12B

1999Bo46: 12C(12B,X) E=920 MeV/nucleon, measured cross section.

2000Ch20: natC(12B,X) E≈930 MeV/nucleon, measured charge-changing σ.

2000Sa47: natC(12B,X) E≈43-97 MeV/nucleon, measured one-neutron removal σ.

2004Sa14: natC(12B,X) E≈43-68 MeV/nucleon, measured one-neutron removal σ, p(11B)parallel distribution.

2010Li18: natSi(12B,X), E=54.4 MeV/nucleon, measured reaction products; deduced total reaction σ.

See analysis in (2010Li18) suggesting Rr.m.s.matter≈2.33 fm and in (2014Es07) suggesting 2.31 fm 7. See also (1990Li39, 1990Lo10, 1999Kn04, 2000Bh09, 2000Ca33, 2001Oz04, 2002Br01, 2003Ca07, 2004Ca45, 2006Bh01, 2006Sh20, 2011Ku06).










E(level)
(keV)
XREFJπ(level) T1/2(level)E(γ)
(keV)
I(γ)M(γ)Final Levels
       0AB DE   IJKLM  PQRSTUVWX Zabc 1+ 20.20 ms 2 
% β- = 100
% β-α = 0.60 2
     
     953.14 60  B DE   IJKL   PQRSTUV X Zabc 2+ 180 fs 28 
% IT = 100
   953.10
  100
M1
       0
1+
    1673.65 60    DE   IJK    PQRST V X Za   2- < 35 fs
% IT = 100
   720.49
  1673.52
    3.3 4 
  100 4 
E1
E1
     953.14
       0
2+
1+
    2620.8 12    DE    JK    PQR T VWX Za   1- < 35 fs
% IT = 100
   947.11
  1667.54
  2620.5
   18 4 
  100 4 
    8 1 
M1
E1
E1
    1673.65
     953.14
       0
2-
2+
1+
    2723 11    DE    JK     Q          b  0+ % IT = 100
  2722.7
  100

       0
1+
    3389.1 16    D    IJK MN PQR   V X Za   3- 3.1 eV 6 
% IT = 0.8
% n = 99.2
     
    3760 6  B D    IJK MN PQ    V X   b  2+ 40 keV 4 
% IT = 8.0×10-4
% n ≈ 100
     
    4000                     V        0-        
    4302 6    D     JK MN PQ    V X      1- 9 keV 4 
% IT = 3.3×10-3
% n ≈ 100
     
    4460             N    S UVWX Za   2- 260 keV
% n ≤ 100
     
    4523 8    D     JK MN PQRS    X Z    4- 110 keV 20 
% IT = 1.8×10-4
% n ≈ 100
     
    4990 12  B D     JK MN P     V     b  1+ 50 keV 15 
% IT = 1.8×10-3
% n ≈ 100
     
    5610 8  B D     JK  N P R   V   Z  c 3+ 115 keV 20 
% n ≤ 100
     
E(level)
(keV)
XREFJπ(level) T1/2(level)E(γ)
(keV)
I(γ)M(γ)Final Levels
    5726 8          JK  N   R     X      3- 58 keV 12 
% n ≤ 100
     
    6000             N                1- % n ≤ 100
     
    6200?                       X             
    6600             N                1+ 140 keV
% n ≤ 100
     
    7060             N                1- % n ≤ 100
     
    7300                      W              
    7545 20          JK  N                < 14 keV
% n ≤ 100
     
    7670       H     N       V        2- 45 keV
% n ≤ 100
     
       7.7E+3 1                   S UV X Za   1- 1.90 MeV 10       
    7800                    U  X  a   4.0 MeV 5       
    7836 20        H J   N                1- 60 keV 40 
% n ≤ 100
     
    7937 20        H J   N                1- < 40 keV
% n ≤ 100
     
    8130 15        H J   N                (3-) 260 keV 80 
% n ≤ 100
     
    8165 25        H  K                   45 keV 15       
    8240 30          J   N                3- 65 keV
% n ≤ 100
     
    8390 20        H JK                   40 keV 15       
    8580 30          JK  N                (3-) 75 keV
% n ≤ 100
     
    8707 20          J   N                (3-) % n ≤ 100
     
    9035 5        H JK  N                1- 95 keV 20 
% n ≤ 100
     
    9175 20          J   N                (2-) % n ≤ 100
     
E(level)
(keV)
XREFJπ(level) T1/2(level)E(γ)
(keV)
I(γ)M(γ)Final Levels
    9300                     V        0- ≈ 330 keV      
    9397 6        H                      35 keV 10       
    9440 8        H JK                   60 keV 20       
    9582 3        H JK  N                3- 34 keV 4 
% n ≤ 100
     
    9758 20          J                           
    9830?         J                           
   10000 40          J   N                100 keV
% n ≤ 100
     
   10115 11        H J           V    a   1- ≈ 200 keV      
   10211 12        H JK     Q             2- 9 keV 3 
% n ≈ 100
     
   10420 10        H J                    LT4- 76 keV 20       
   10564 3        H JK  N  Q             2- 11 keV 3 
% n = 80
% α = 20
     
   10580?              O               200 keV
% n < 100
% α < 100
     
   10881 4      F H JK     Q             3+ 17 keV 4       
   11080?         J                    % α ≤ 100
     
   11337 7        H J                    LT8 90 keV 25       
   11573 6     EF H J                    LT8 60 keV 20 
% α = 100
     
   12227 9        H     N                155 keV 60 
% n ≤ 100
     
   12335 15        H JK                   62 keV 25       
   12733 40                         Y   c 0+ < 40 keV
% α = 100
     
   12760 15        H J                    110 keV 35       
E(level)
(keV)
XREFJπ(level) T1/2(level)E(γ)
(keV)
I(γ)M(γ)Final Levels
      12.8E3 5                        X      3.5 MeV 5       
   13310 15        H J              Y     53 keV 12 
% α ≤ 100
     
      13.4E+3 1   C EF    K              Z    % α = 100
     
  ≈14100  C EFG  J                    % α > 94.4
% 3H < 5.1
     
   14820 50                         Y   c 2+ < 100 keV
% p = 0.2
% 3H = 23.8
% α = 76.0
     
  ≈15700  C EF   J                    % α > 99.6
% 3H < 0.4
     
   17400     F                        % α ≤ 100
     
      17.8E3 15          J             X      3.5 MeV 15 
% α ≤ 100
     
   18200                          a          

E(level): The (1990Aj01) evaluation identified states at Ex=21.8 and 23.9 MeV, however this result was obtained from a misinterpretation of (1987Na16).

T1/2(level): LABEL=t or Γ

E(γ): From level energy difference; recoil correction applied

I(γ): Percent photon branching from each level

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Additional Gamma Data:











E(level)
(keV)
Jπ(level)T1/2(level)E(γ)
(keV)
MultipolarityAdditional Data
     953.14 2+ 180 fs 28 
% IT = 100
   953.10M1B(M1)(W.u.)=0.14 2
    1673.65 2- < 35 fs
% IT = 100
   720.49E1B(E1)(W.u.)>0.003
2- < 35 fs
% IT = 100
  1673.52E1B(E1)(W.u.)>0.008
    2620.8 1- < 35 fs
% IT = 100
   947.11M1B(M1)(W.u.)>0.11
1- < 35 fs
% IT = 100
  1667.54E1B(E1)(W.u.)>0.0066
1- < 35 fs
% IT = 100
  2620.5E1B(E1)(W.u.)>1.3E-4

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Additional Level Data and Comments:

E(level)Jπ(level)T1/2(level)Comments
       01+ 20.20 ms 2 
% β- = 100
% β-α = 0.60 2
Q=0.0134 14, μ=+1.00306 15, T=1
T1/2: From (1978Al01). Earlier values are reported in (1968Aj02). The next most significant reported values are: 20.3 ms 1 (1963Fi05), 20.2 ms 2 (1963Pe10), 20.80 ms 15 (1962Ne14), 20.15 ms 20 (1962Po02), 20.31 ms 20 (1961Sc09) and 20.6 ms 2 (1958Kr65).
E(level): T1/2: From (1978Al01). Earlier values are reported in (1968Aj02). The next most significant reported values are: 20.3 ms 1 (1963Fi05), 20.2 ms 2 (1963Pe10), 20.80 ms 15 (1962Ne14), 20.15 ms 20 (1962Po02), 20.31 ms 20 (1961Sc09) and 20.6 ms 2 (1958Kr65).
     953.142+ 180 fs 28 
% IT = 100
T1/2: From average of (1968Ol01,1969Ga16,1970Ga09).
E(level): T1/2: From average of (1968Ol01,1969Ga16,1970Ga09).
    1673.652- < 35 fs
% IT = 100
T1/2: From (1968Ol01).
E(level): T1/2: From (1968Ol01).
    2620.81- < 35 fs
% IT = 100
T1/2: From (1969Th01).
E(level): T1/2: From (1969Th01).
    3389.13- 3.1 eV 6 
% IT = 0.8
% n = 99.2
Γn=3.1 eV 6, Γγ=25 meV 8 (1969Mo10).
    37602+ 40 keV 4 
% IT = 8.0×10-4
% n ≈ 100
Γγ=0.30 eV 15 (1962Im01).
    40000-   E(level): Decay mode not specified.
    43021- 9 keV 4 
% IT = 3.3×10-3
% n ≈ 100
Γγ=0.30 eV 15 (1962Im01).
    44602- 260 keV
% n ≤ 100
E(level): Spin Dipole Resonance.
    45234- 110 keV 20 
% IT = 1.8×10-4
% n ≈ 100
Γγ=0.3 eV 1 (1962Im01).
E(level): Spin Dipole Resonance.
    49901+ 50 keV 15 
% IT = 1.8×10-3
% n ≈ 100
Γγ=0.9 eV 5 (1962Im01).
    6200   E(level): Decay mode not specified.
    7300   E(level): Decay mode not specified.
       7.7E+31- 1.90 MeV 10  E(level): Spin Dipole Resonance. Decay mode not specified.
    7800 4.0 MeV 5  E(level): Decay mode not specified.
    8165 45 keV 15  E(level): Decay mode not specified.
    8390 40 keV 15  E(level): Decay mode not specified.
    93000- ≈ 330 keV In (2017Ke05), two Jπ=0- levels were listed from 12C(d,2p). Only the level at Ex=9.3 MeV should have been listed.
E(level): In (2017Ke05), two Jπ=0- levels were listed from 12C(d,2p). Only the level at Ex=9.3 MeV should have been listed. Decay mode not specified.
    9397 35 keV 10  E(level): Decay mode not specified.
    9440 60 keV 20  E(level): Decay mode not specified.
    9758   E(level): Decay mode not specified.
    9830   E(level): Decay mode not specified.
   101151- ≈ 200 keV E(level): Decay mode not specified.
   10420LT4- 76 keV 20  E(level): Decay mode not specified.
   11337LT8 90 keV 25  E(level): Decay mode not specified.
E(level)Jπ(level)T1/2(level)Comments
   12335 62 keV 25  E(level): Decay mode not specified.
   12760 110 keV 35  E(level): Decay mode not specified.
      12.8E3 3.5 MeV 5  E(level): Decay mode not specified.
   18200   E(level): Decay mode not specified.

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Additional Gamma Comments:

E(level)E(gamma)Comments
    1673.65     720.49I(γ): From (1968Ol01).

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