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GENERAL: See Table 14.26 [Table of Energy Levels] (in PDF or PS).

See (1959OT1A, 1960PI1C, 1960TA1C, 1961FR1C, 1963BL1B, 1964LO1B, 1965KO1D, 1966BO1R, 1966KE16, 1966MI1G, 1967AU1B, 1968EI1C, 1968FA1B, 1968NE1C, 1969GA1G, 1969SO08).

1. 14O(β+)14N

Qm = 5.144

The decay proceeds primarily to the J^π = 0⁺; T = 1 first excited state of ¹⁴N: see Table 14.27 (in PDF or PS). Weak branches are also observed to the ground state of ¹⁴N and to the 3.95 MeV state.

The ground-state decay is considerably faster than the mirror transition ¹⁴C → ¹⁴N supporting the hypothesis that both decays are inhibited by accidental cancellation of matrix elements: see ¹⁴C and (1968RO1C).

The decay of ¹⁴N*(2.31) is an example of pure Fermi 0 → 0 transition and provides a precise determination of the fundamental coupling constant G_V (see surveys by (1964WU01, 1966FR15, 1968MO1F)). G_V = 1.4025 × 10^-49 erg · cm³ (1962BA26), 1.409 × 10^-49 erg · cm³ (1968BR1L: see (1969DA06)), 1.407 × 10^-49 erg · cm³ (1969DA06). See also (1959KI1C, 1960BA36, 1967BL24, 1968BE03). According to the hypothesis of a universal weak interaction, with conserved vector current, G_V = G_μ, the coupling constant for muon decay. The mean for seven cases cited by (1966FR15) is (G_μ - G_V/G_μ = (2.2 ± 0.1 ± 0.5)%, where the second error reflects the uncertainty of radiative corrections. See also (1962BA26, 1968BR1L, 1969BL1E, 1969DA06).

The transition to ¹⁴N*(3.95) appears to be super allowed. See also (1962BR16, 1964GA1B, 1966FR15, 1966CH1J, 1966MAZY, 1969LO1F).

The polarization of the positrons has been studied by (1959GE36, 1961HO04). See also (1959AJ76) and (1958AL1E, 1959JA1B, 1960DU1B, 1961BL1A, 1962AL1F, 1962WE09, 1962WE1H, 1962BL1D, 1963LO04, 1964BA1T, 1965BL1E, 1964NA1C, 1965MI1B, 1966BA1A, 1966MA57, 1967CH24, 1967SA1H, 1968BH1C, 1968DA1J, 1968HA38, 1968LA1J, 1968YA1F).

2. 10B(6Li, 2n)14O

Qm = 1.990

See (1957NO17).

3. 12C(3He, n)14O

Qm = -1.148

Reported values of the threshold energy are displayed in Table 14.28 (in PDF or PS). Neutron groups have been observed corresponding to ¹⁴O states at 5.17 (1967AD1D, 1968TO09), 5.905 ± 0.012, 6.30 ± 0.03 and 6.586 ± 0.012 MeV, with widths ≤ 60, 120 and ≤ 60 keV, respectively (1961TO03). Higher excited states at 7.78 (1967AD1D), 8.0 ± 0.4, 10.1 ± 0.4 and 13.3 ± 0.4 MeV are reported by (1964BR13). Angular distributions are reported at many energies from 1.9 to 25 MeV: see (1957BR18, 1960AJ03, 1960GA13, 1963MA22, 1964DE1C, 1964DI02, 1964KU05, 1967AD1D, 1967MC03, 1967SC27, 1968TO09).

The angular distributions for n₀ and for p₁, to ¹⁴N*(2.3), show strng forward peaking in the range E(³He) = 6.5 to 11 MeV. The distributions are similar in detail, and well fitted by plane wave direct interaction theory with L = 0. Excitation functions at θ = 10° show marked energy dependence, but (dσ_n/dσ_p) is nearly constant at the expected value of 2.0 (1965FU16). Angular distributions (at E(³He) = 9.2 and 10.2 MeV) of the ³He groups to ¹⁴O*(0, 5.17, 5.91, 6.29), analyzed by DWBA double stripping theory, give L = 0; L = 1 or (0); L = 0 or (1); L = 3 or 4, respectively. These fits, taken together with the relatively sharp widths of the three excited states (see Table 14.25 (in PDF or PS)), lead to probable J^π for ¹⁴O*(5.17, 5.91, 6.29) of 1^-, 0⁺, 3^-, respectively (1968TO09). See also (1960NE1A, 1961GI1B, 1963GL1C, 1964HE06, 1965BR1H, 1966HA1Q, 1966SH1F, 1967CH19) and ¹⁵O.

4. 14N(p, n)14O	Qm = -5.927
		Ethresh. = 6.3544 ± 0.0016 (1968FR08);
		Ethresh. = 6.3588 ± 0.0030 (1956KU1A; see also (1964KU06)).

The angular distribution of ground state neutrons has been determined at E_p = 14.8 and 31.5 MeV (1960DA06, 1961AD02). Neutron groups are reported corresponding to broad or unresolved states at E_x ≈ 6.2, 7.5 and 9.3 MeV (1954AJ11). See also (1966SI05, 1968RI1Q, 1969MA1G, 1969PA1J, 1969VE02).

5. 14N(3He, t)14O

Qm = -5.163

Triton groups observed at E(³He) = 44.6 MeV are displayed in Table 14.29 (in PDF or PS). Comparisons of angular distributions of the tritons to the first eight states of ¹⁴O with those of triton groups in other reactions involving known l-transfers lead to the J^π assignements quoted in the table (1967BA13, 1969BA06). See also (1968BA1E) and reaction 45 in ¹⁴N.

6. 16O(γ, 2n)14O

Qm = -28.887

See (1959OC07, 1962BR16, 1964MO26).

7. 16O(p, t)14O

Qm = -20.406

The angular distribution of ground state protons has been determined at E_p = 43.7 (1964CE02). See also (1966CE05, 1969SO08).