List of levels for 18NA

All experimental evidence is consistent with the scenario that all levels of ¹⁸Na proton decay 100% to levels in ¹⁷Ne.

Existing evidence suggests a ground state near E_res(cm)=1.25 MeV (Γ≈0.54 MeV) inspite of evidence for a resonance that decays with E_cm(p+¹⁷Ne)=0.41 MeV 16 (Γ≈340 keV). The later strength is likely a higher energy state that decays to a ¹⁷Ne excited state, hence the resonant decay energy does not trivially reflect the excitation energy or missing mass. Wang and Audi et al. take ΔM=25040 keV 110 [E_cm(p+¹⁷Ne)=1.25 MeV 11] as the ground state energy; we accept the ¹⁸Na ground state at S_p=1.25 MeV 11 (2012Wa38).

Theoretical works:

Using analysis of the mirror ¹⁸N system, frameworks are developed describing the low-lying levels of ¹⁸Na in terms of ¹⁹Na plus a neutron hole (2005Fo13) or ¹⁷Ne plus a proton (2006Fo08). Estimates on the mass excess and level spacings are discussed. In (2012Fo10) the approach was updated using newly available data.

See other analyses in (1928Gu10, 1984An18, 1987Po01, 2004Ge02, 2008Qi04).

Q(β-)=-17.39×10³ keV 15	S(n)= 17.35×10³ keV 15	S(p)= -1.25×10³ keV 11	Q(α)= -9.34 keV 12
Reference: 2012Wa38

E(level) (keV)	XREF	J^π(level)	T_1/2(level)
0	B	(1)-	< 0.2 MeV % p ≈ 100.
0.30E3 11	A B	2-	5 keV 3 % p ≈ 100.
0.59E3 12	A	0-	300 keV 100 % p ≈ 100.
0.78E3 11	A	1-	900 keV 100 % p ≈ 100.
0.83E3 11	A	3-	42 keV 10 % p ≈ 100.

E(level)	J^π(level)	T_1/2(level)	Comments
0	(1)-	< 0.2 MeV % p ≈ 100.	Excitation energies are reported with respect to E_res(p+¹⁷Ne)=1.25 MeV 11, the accepted value in (2012Wa38). E(level): Excitation energies are reported with respect to E_res(p+¹⁷Ne)=1.25 MeV 11, the accepted value in (2012Wa38).