ADOPTED LEVELS, GAMMAS for 18N

Authors: R. Spitzer, J.H. Kelley |  Citation: ENSDF |  Cutoff date: 30-Jun-2021 

 Full ENSDF file | Adopted Levels (PDF version) 


Q(β-)=13896 keV 19S(n)= 2828 keV 24S(p)= 15208 keV 25
Reference: 2021Wa16

References:
  A  18C β- decay  B  19C β-n decay
  C  2H(17N,p)  D  9Be(11B,2pγ)
  E  12C(18N,X)  F  9Be(18O,p2α)
  G  9Be(18O,18N):MOMENT  H  9Be(19N,18N)
  I  9Be(22Ne,18N)  J  9Be(40Ar,18N)
  K  12C(22Ne,18N)  L  14C(7Li,3He)
  M  14C(18O,18N)  N  18O(π-,γ)
  O  18O(n,p)  P  18O(d,2He)
  Q  18O(t,3He)  R  18O(7Li,7Be)
  S  18O(11B,11C)  T  18O(18O,18N)
  U  28Si(p,18N):SPALLATION  V  181Ta(18O,18NG)
  W  181Ta(22Ne,18N)  X  232Th(p,18N)
  Y  232Th(18O,18N),(22Ne,18N) 

General Comments:

Prior reviews: 1972Aj02, 1978Aj05, 1983Aj01, 1987Aj02, 1995Ti07.

Shell Model analysis of 18N:

The ground state spin of 18N is Jπ=1- (1982Ol01) while a simple shell-model analysis predicts Jπ=2-. Detailed discussion is given (1983Sh44, 1984Ba24, 2012Yu07, 2018Ji07).

See other relevant theoretical analysis in:

1988PoZS, 1993Pa14, 1993Po11, 1997Ba54, 2000Zh42, 2004La24, 2004Ne16, 2004Su23, 2005Fo13, 2006Ko02, 2016Ma06, 2018Fo04, 2018Fo17, 2019Fo08

Other relevant reaction studies:

1981SuZS, 1987Su06: Systematic measurement of μ- capture rates.

1983As01, 1984As05: 18O(π-0). Studied isospin dependence of single-charge-exchange reactions for (π|+0) reactions at LAMPF. See also (1980Ge09, 1982ArZT).

1998Mu17: Theoretical analysis on μ capture rates on light nuclei.

1999He33: Theoretical analysis of astrophysically relevant neutron capture in unstable nitrogen nuclei

2019Zh29: Calculated μ- spalation yields on Ar leading to 18N, which is a source of background in the DUNE neutrino detector.









E(level)
(keV)
XREFJπ(level) T1/2(level)E(γ)
(keV)
I(γ)Final Levels
     0.0AB DEFGHIJKLMNOPQR TUVWXY 1- 619 ms 2 
% β- = 100
% β-n = 12.0 13
% β-α = 12.2 6
    
   114.71 10 ABCD   H       P R   V    (2-) 0.40 ns 11 
% IT = 100
   114.7 1 
  100
     0.0
1-
   587.39 20 AB D   H   LM     ST V    (2-) % IT = 100
   472.7 2 
  100 16 
   114.71
(2-)
   742.0 4   CD   H   L     R   V    (3-) % IT = 100
   154.6 3 
   627 1 
   20
  100
   587.39
   114.71
(2-)
(2-)
  1170 20   C          N            (1-) % IT = 100
    
  1734.75 19 A                         (1,2) % IT = 100
  1147.8 4 
  1619.9 3 
  1734.8 4 
   68 20 
  100 25 
  100 25 
   587.39
   114.71
     0.0
(2-)
(2-)
1-
  2210  C              R        % IT = 100
    
  2405.0 9                  R   V    0.11 ps +51-7 
% IT = 100
  1663.0 8 
  100
   742.0
(3-)
  2614.35 21 A                         1+ % IT = 100
   879.7 2 
  2025.3 8 
  2499.3 4 
  2614.2 4 
   44 4 
    7 5 
   41 9 
  100 11 
  1734.75
   587.39
   114.71
     0.0
(1,2)
(2-)
(2-)
1-
     2.9E3 2 ?             N                  
     6.9E3 2 ?             N                  
     8.5E3 2 ?             N                  
    10.1E3 2 ?             N                  

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Additional Level Data and Comments:

E(level)Jπ(level)T1/2(level)Comments
   114.71(2-) 0.40 ns 11 
% IT = 100
E(level): From least squares fit to (Ex: Eγ), (115: 114.7 1), (587: 472.7 2), (742: 154.6 3, 627 1), (1735: 1147.8 4, 1619.9 3, 1734.8 4), (2405: 1663.0 8), (2614: 879.7 2, 2025.3 8, 2499.3 4, 2614.2 4) from averages of γ energies given in 18C β- (1991Pr03), 9Be(11B,2pγ) (2008Wi05) and 181Ta(18O,18Nγ) (2020Zi03).
Jπ(level): Suggested by theory (1984Ba24). See also (1982Ol01,1991Pr03).
   587.39(2-) % IT = 100
E(level): From least squares fit to (Ex: Eγ), (115: 114.7 1), (587: 472.7 2), (742: 154.6 3, 627 1), (1735: 1147.8 4, 1619.9 3, 1734.8 4), (2405: 1663.0 8), (2614: 879.7 2, 2025.3 8, 2499.3 4, 2614.2 4) from averages of γ energies given in 18C β- (1991Pr03), 9Be(11B,2pγ) (2008Wi05) and 181Ta(18O,18Nγ) (2020Zi03).
Jπ(level): Suggested by theory (1984Ba24). See also (1982Ol01,1991Pr03).
   742.0(3-) % IT = 100
E(level): From least squares fit to (Ex: Eγ), (115: 114.7 1), (587: 472.7 2), (742: 154.6 3, 627 1), (1735: 1147.8 4, 1619.9 3, 1734.8 4), (2405: 1663.0 8), (2614: 879.7 2, 2025.3 8, 2499.3 4, 2614.2 4) from averages of γ energies given in 18C β- (1991Pr03), 9Be(11B,2pγ) (2008Wi05) and 181Ta(18O,18Nγ) (2020Zi03).
Jπ(level): Suggested by theory (1984Ba24). See also (1982Ol01,1991Pr03).
  1734.75(1,2) % IT = 100
E(level): From least squares fit to (Ex: Eγ), (115: 114.7 1), (587: 472.7 2), (742: 154.6 3, 627 1), (1735: 1147.8 4, 1619.9 3, 1734.8 4), (2405: 1663.0 8), (2614: 879.7 2, 2025.3 8, 2499.3 4, 2614.2 4) from averages of γ energies given in 18C β- (1991Pr03), 9Be(11B,2pγ) (2008Wi05) and 181Ta(18O,18Nγ) (2020Zi03).
Jπ(level): See (1993Ch06).
  2405.0 0.11 ps +51-7 
% IT = 100
E(level): From least squares fit to (Ex: Eγ), (115: 114.7 1), (587: 472.7 2), (742: 154.6 3, 627 1), (1735: 1147.8 4, 1619.9 3, 1734.8 4), (2405: 1663.0 8), (2614: 879.7 2, 2025.3 8, 2499.3 4, 2614.2 4) from averages of γ energies given in 18C β- (1991Pr03), 9Be(11B,2pγ) (2008Wi05) and 181Ta(18O,18Nγ) (2020Zi03).
  2614.351+ % IT = 100
E(level): From least squares fit to (Ex: Eγ), (115: 114.7 1), (587: 472.7 2), (742: 154.6 3, 627 1), (1735: 1147.8 4, 1619.9 3, 1734.8 4), (2405: 1663.0 8), (2614: 879.7 2, 2025.3 8, 2499.3 4, 2614.2 4) from averages of γ energies given in 18C β- (1991Pr03), 9Be(11B,2pγ) (2008Wi05) and 181Ta(18O,18Nγ) (2020Zi03).
Jπ(level): See (1993Ch06).

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Additional Gamma Comments:

E(level)E(gamma)Comments
   742.0   627I(γ): From (2008Wi05)
  1734.75  1734.8I(γ): α discrepancy exists between the (1991Pr03) Table 1 and Table 3 γ-ray intensities for Ex=1734 keV; we use values from Table 1. This choice is necessary to reproduce their relative β- feedings to 18N*(1734,2614).
  2405.0  1663.0I(γ): From (2020Zi03)

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