A=18F (1987AJ02)

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¹⁸F (1987AJ02)

(See Energy Level Diagrams for ¹⁸F)

GENERAL: See (1983AJ01) and Table 18.13 [Table of Energy Levels] (in PDF or PS).

Shell model: (1978WI1B, 1982ZH01, 1983BR29, 1983KI13, 1984MI1H, 1984MI17, 1985LE1K, 1986YU1B).

Cluster, collective and deformed models: (1983ME12, 1984QU1A, 1985BA1A, 1987ER05).

Special states: (1978WI1B, 1982ZH01, 1983BI1C, 1983BR29, 1983ME12, 1983KI13, 1984AD1E, 1984HA14, 1984HO1H, 1984MI1H, 1984MI17, 1985AD1A, 1985HA18, 1985LE1K, 1985MI10, 1985SO12, 1985YU1B, 1986AN07, 1986CA27, 1986HA1E, 1986HA1Q, 1986SI1K, 1986TO1D, 1986WI1P, 1986YU1B, 1987ER05).

Electromagnetic transitions: (1982RI04, 1983BR29, 1983KI13, 1984BI10, 1984HA14, 1984MI1H, 1984QU1A, 1985AD1A, 1986CA27, 1986SI1K, 1987ER05, 1987KI03).

Astrophysical questions: (1982WI1B).

Applications: (1982HI1H, 1982YA1C, 1984HI1D, 1984NI1C, 1985HU02, 1986HI1B, 1987HI1B).

Complex reactions involving ¹⁸F: (1983DE26, 1983JA05, 1983OL1A, 1983WI1A, 1984GR08, 1984HI1A, 1984HO23, 1985BE40, 1985CU1C, 1985DR07, 1985GR1K, 1985PO11, 1986AV07, 1986BA3G, 1986GR1A, 1986HA1B, 1986HO27, 1986PO06, 1986SC28, 1986SC29, 1986VA23, 1987RI03, 1987RO10).

Pion capture and reactions (See also reaction 32.): (1982LI15, 1983HO02, 1986GE06, 1986NA1K).

Hypernuclei: (1984AS1D).

Other topics: (1978WI1B, 1983AD1B, 1983AG1C, 1983AR1J, 1983BI1C, 1983BR29, 1983SH32, 1984BI10, 1984HO1H, 1984MI1H, 1985AD1A, 1985AN28, 1985MI10, 1985YU1B, 1986LA29, 1986NA1K, 1986TO1D, 1987KI03).

Ground and 1.12 MeV states of ¹⁸F: (1978WI1B, 1983ANZQ, 1983AR1J, 1984HA14, 1985AN28, 1985HA18, 1986CA27).

μ_1.12 = +2.86 ± 0.03 nm [see (1983AJ01)]

Q_1.12 = 0.13 ± 0.03 b [see (1983AJ01)].

1. ¹⁸F(β⁺)¹⁸O Q_m = 1.6554

The positron decay is entirely to the ground state of ¹⁸O [J^π = 0⁺, T = 1]; the half-life is 109.77 ± 0.05 min [see Table 18.11 (in PDF or PS) in (1972AJ02)]; log ft= 3.554. The fact that the β⁺ transition to ¹⁸O_g.s. is allowed indicates J^π = 1⁺ for ¹⁸F_g.s.. The ratio ε_K/β⁺ = 0.030 ± 0.002: see (1978AJ03). See also (1985BR29), (1982KA1C; applications), (1985AR1A, 1985KL1A, 1986HE1C, 1987GOZX; astrophyics) and (1983CA03; theor.) [see for discussions of weak magnetism form factor and of search for heavy neutrinos].

2. (a) ¹⁰B(⁹Be, n)¹⁸F Q_m = 14.4539
(b) ¹¹B(⁹Be, 2n)¹⁸F Q_m = 2.9998

See (1986CU02) for production cross sections of 0.94 MeV γ-rays.

3. (a) ¹²C(⁶Li, d)¹⁶O Q_m = 5.6868 E_b = 13.212
(b) ¹²C(⁶Li, α)¹⁴N Q_m = 8.7972
(c) ¹²C(⁶Li, ⁶Li)¹²C

Cross sections for these and other charged particle channels have been measured for E(⁶Li) = 1.9 to 36 MeV [see (1978AJ03, 1983AJ01)].

The cross section for the isospin-forbidden α₁ group [to ¹⁴N*(2.31), 0⁺, T = 1] is 1 to 2% of the cross section to the allowed α₀ and α₂ groups for E(⁶Li) = 3.2 to 6 MeV while for 9 to 14 MeV it varies from 0.4 to 1.8%. At 20 MeV, the α₁ yield is 0.02% of the allowed yield. Structures are reported at E(⁶Li) = 11.0 and 13.0 MeV in the α₀ yield, at 11.5 and (13.0) MeV in the α₁ yield and at ≈ 11.7 and 12.8 MeV in the α₂ yield. A resonance is also reported in the α₁ yield at E(⁶Li) = 4.2 MeV: E_x = 15.99 ± 0.02 MeV, Γ_c.m. = 290 ± 30 keV, J^π = 2⁺ (one-level BW fit). It is suggested that this resonance is due to 2⁺ states with T = 0 and T = 1 which are unresolved. Cross sections for populating ¹⁶O*(8.87, 10.36, 11.08, 11.10) are reported by (1981GL02).

The excitation functions for the ⁶Li ions to ¹²C*(0, 4.43) shows a single isolated structure at E(⁶Li) = 22.8 MeV, in the range 20 - 36 MeV, with Γ ≈ 0.8 MeV. It is unlikely to be due to an isolated state in ¹⁸F. At E(pol. ⁶Li) = 20 MeV analyzing power measurements are reported for many deuteron and α groups and for elastically scattered ⁶Li ions. VAP measurements for elastic scattering are also reported at E_{pol. d} = 9.0 and 19.2 MeV (1983RU09) and at 150 MeV (1986TA1B, 1986KA1C).

For fusion studies see (1982DE30, 1987PA12). For references to earlier work and for additional comments see (1978AJ03, 1983AJ01). See also (1980KR1F), (1984MU1D; theor.) and ¹²C in (1985AJ01), ¹⁴N in (1986AJ01) and ¹⁶O in (1986AJ04).

4. ¹²C(⁹Be, t)¹⁸F Q_m = -4.4754

Angular distributions are reported at E(⁹Be) = 12 to 27 MeV to ¹⁸F_g.s. and to the unresolved states at 1 MeV: see (1983AJ01). For excitation functions see (1982HU06, 1983JA09).

5. ¹²C(¹¹B, αn)¹⁸F Q_m = -2.7015

τ_m = 5.2 ± 0.9 psec for ¹⁸F*(4.85) [5^-; T = 0]. The E1 strength is (3.4 ± 0.6) × 10^-6 W.u. for the transition to ¹⁸F*(1.12) [5⁺; T = 0] and the E2 strength is 14.8 ± 2.6 W.u. for that to ¹⁸F*(3.79) [3^-; 0]. The latter strength, which is that of a highly collective transition, corresponds to a quadrupole moment Q₀ = 395 ± 35 mb and suggests that ¹⁸F*(4.85) is the 5^- state of a (strongly decoupled) K^π = 1^- band 1982KO24). See also Tables 18.14 (in PDF or PS) and 18.15(in PDF or PS).

6. ¹⁴N(α, γ)¹⁸F Q_m = 4.4152

The non-resonant S-factor for this reaction, S ≈ 0.7 MeV · b: see (1978AJ03). A number of resonances have been observed for E_α < 3 MeV: see Table 18.16 (in PDF or PS). Studies of these, principally by the Toronto and Queen's groups [see references in (1978AJ03, 1983AJ01)] in conjunction with work on ¹⁴N(α, α), ¹⁶O(³He, p), ¹⁷O(p, γ) and ¹⁷O(p, α) [see Tables 18.18 (in PDF or PS), 18.19 (in PDF or PS), 18.20 (in PDF or PS)] have led to the determination of branching ratios, mixing ratios and widths (Table 18.14 (in PDF or PS)), lifetimes (Table 18.15 (in PDF or PS)) and the E_x, J^π and K^π assignments for ¹⁸F states with E_x < 6.9 MeV. The reader is referred to the series of papers by the Toronto group for the most complete and definitive arguments on the parameters of the low-lying states of ¹⁸F.

No evidence is seen for the excitation of the (forbidden) state at E_x = 4.753 MeV [J^π = 0⁺; T = 1] (1981LE1A, 1983LE08). See also (1985GO27; applications) and (1982BA1D, 1985AR1A, 1985KL1A, 1985MA1A, 1986HE1C, 1981LE1A, 1987GOZX; astrophysics).

7. ¹⁴N(α, p)¹⁷O Q_m = -1.1914 E_b = 4.4152

Observed resonances are displayed in Table 18.16 (in PDF or PS). See also ¹⁷O in (1986AJ04).

8. (a) ¹⁴N(α, α)¹⁴N E_b = 4.4152
(b) ¹⁴N(α, 2α)¹⁰B Q_m = -11.6123
(c) ¹⁴N(α, ⁶Li)¹²C Q_m = -8.7972

Observed anomalies in the elastic scattering [reaction (a)] are exhibited in Table 18.16 (in PDF or PS). Resonances in the α₁ isospin-forbidden yield are displayed in Table 18.14 (in PDF or PS) of (1978AJ03). In the α₁ study, carried out for E_α = 7.6 → 16.9 MeV, a partial-wave analysis involving a method of removing ambiguities and parametrizing S-matrix elements gives the level parameters of 151 isospin mixed, natural-parity states in ¹⁸F with 10.4 < E_x < 17.5 MeV. Many of these states have also been reported in the ¹⁶O(d, α₁) reaction [Table 18.16 (in PDF or PS) of (1978AJ03)]. The argeement is best for low-lying 2⁺ or 4⁺ states, and is quite good for 3^- and 5^- states, while for high-J states the greater centrifugal barrier for ¹⁶O + d at the same E_x relatively suppresses high-J states in the ¹⁶O + d work. A study of the energy dependence of averaged intensities of the partial waves shows some indication that the lower partial waves reconserve isospin as E_x increases.

The total cross sections for formation of ¹⁰B and ⁶Li have been studied for E_α = 21 to 42 MeV [see (1978AJ03)], as has the cross section for production of 1.64 and 2.31 MeV γ-rays from threshold to E_α = 26 MeV [(1985DY05): see for astrophysical implications.] See also (1984RE14, 1986CO11) and (1986ALZZ; theor.).

9. (a) ¹⁴N(⁶Li, d)¹⁸F Q_m = 2.940
(b) ¹⁴N(⁶Li, dα)¹⁴N Q_m = -1.4751

At E(⁶Li) = 36 MeV angular distributions have been measured for the deuteron groups to ¹⁸F*(5.34 [4⁺], 6.56 [5⁺], 9.58, 11.2, 14.1). Angular correlations lead to J^π = 6⁺ and 8⁺ for ¹⁸F*(9.58, 14.1) and the data are consistent with J^π = 7⁺ for ¹⁸F*(11.2) (1983ET02). For the earlier work see (1978AJ03).

10. ¹⁴N(⁷Li, t)¹⁸F Q_m = 1.947

At E(⁷Li) = 36 MeV the K^π = 1⁺ band appears to be selectively populated. States at E_x=9.58 ± 0.02, 11.22 ± 0.03 and 14.18 ± 0.04 MeV are stongly populated. It is suggested that the first two are the 6⁺ and 7⁺ members of that band: see reaction 8. [Angular distributions are reported for ¹⁸F*(1.70, 2.10, 2.52, 3.36, 4.40, 5.30, 6.57, 9.58, 11.22, 14.18).] See (1978AJ03) for the earlier work, and (1986NE1A; E(¹⁴N) = 150 MeV). See also (1986CO11; theor.).

11. (a) ¹⁴N(¹¹B, ⁷Li)¹⁸F Q_m = -4.249
(b) ¹⁴N(¹³C, ⁹Be)¹⁸F Q_m = -6.2324

These reactions have been studied at E(¹¹B) = 115 MeV and E(¹³C) = 105 MeV. Differential cross sections at three angles are reported for the transitions to ¹⁸F*(9.58, 10.57 ± 0.07, 11.2) in reaction (a) and to ¹⁸F*(5.30, 6.57, 9.58, 10.60 ± 0.08, 11.2) in reaction (b). In addition to these states ¹⁸F*(14.18) is strongly excited in both reactions, and transitions to ¹⁸F*(15.79 ± 0.10, 18.62 ± 0.12) are also reported: see (1983AJ01).

12. (a) ¹⁵N(³He, γ)¹⁸F Q_m = 14.1596
(b) ¹⁵N(³He, α)¹⁴N Q_m = 9.7445 E_b = 14.1596

Excitation functions have been measured for E(³He) = 2.5 to 16 MeV for the γ₀ and γ₁ → 4 yields. Resonances are observed corresponding to E_x = (19.00 ± 0.15) [γ₁ → 4], 20.1 ± 0.2 [γ₀, γ₁ → 4], 22.7 ± 0.2 [γ₀, γ₁ → 4] and (24.1 ± 0.2) MeV [γ₁ → 4], with Γ_c.m. = 0.5 ± 0.15, 1.6 ± 0.1, 1.2 ± 0.1 and 1.4 ± 0.3 MeV, respectively. The γ₀ yield is dominated by ¹⁸F*(20.1) (1983WA05) [see for (2J + 1)Γ_³HeΓ_γ values]. It is suggested that the structures decaying by γ₀ have J^π = 2^- (and possibly T = 1) (1983WA05). For analyzing power measurements at E(pol. ³He) = 33 MeV see (1986DR03).

13. ¹⁵N(⁶Li, t)¹⁸F Q_m = -1.636

At E(⁶Li) = 30 MeV preferential excitation of odd-parity states of ¹⁸F below E_x = 5 MeV is reported. Angular distributions of the tritons to ¹⁸F*(0, 0.94, 2.10, 4.40) [J^π = 1⁺, 3⁺, 2^-, 4^-] are all strongly forward peaked: see (1978AJ03).

14. (a) ¹⁵N(¹¹B, ⁸Li)¹⁸F Q_m = -13.049
(b) ¹⁵N(¹²C, ⁹Be)¹⁸F Q_m = -12.1194

These reactions have been studied with E(¹¹B) = E(¹²C) = 115 MeV. Reaction (a) is dominated by the transitions to ¹⁸F*(1.12) [presumably the J^π = 5⁺ state, although the group is unresolved] and to ¹⁸F*(7.15, 9.45) [J^π = (7^-) and (6^-)]. In reaction (b) no single state is strongly preferentially populated. Differential cross sections for ¹⁸F*(4.40, 6.10, 7.15, 9.45) [J^π = 4^-, (5^-), (7^-), (6^-)], are fitted by FRDWBA: see (1983AJ01).

15. ¹⁶O(d, γ)¹⁸F Q_m = 7.5256

The capture cross section rises from 0.1 μb at E_d = 0.4 MeV to 25 μb at 3.5 MeV: Γ_γ over this range is ≈ 2 eV: see (1972AJ02).

16. (a) ¹⁶O(d, n)¹⁷F Q_m = -1.6241 E_b = 7.5256
(b) ¹⁶O(d, p)¹⁷O Q_m = 1.9191

Excitation functions and polarization studies have been carried out to E_d = 17 MeV [see (1978AJ03, 1983AJ01)] and at E_d ≈ 5.6 to 8.3 MeV (1985GR1B; p₀, p₃, p₄). Structures attributed to states in ¹⁸F are displyed in Table 18.17 (in PDF or PS). See also ¹⁷O and ¹⁷F in (1986AJ04), (1985JOZZ, 1986SE1B) and (1983DA31; applications).

17. ¹⁶O(d, d)¹⁶O E_b = 7.5256

The yield of elastically scattered deuterons and elastic polarization measurements have been reported for E_d = 0.65 to 56 MeV: see (1978AJ03, 1983AJ01). More recent measurements are those by (1985GR1B) [excitation functions for E_d ≈ 5.6 to 8.3 MeV] and the polarization studies at E_{pol. d} = 20.5 MeV (1984FR14; TAP), 56 MeV (1986MA32; VAP, TAP) and 200, 400 and 700 MeV (1987NG01; VAP, TAP). See also (1982AO06, 1983AO03, 1986NG1B, 1986YA1R, 1987MA09; theor.) and ¹⁶O in (1986AJ04).

18. ¹⁶O(d, α)¹⁴N Q_m = 3.1104 E_b = 7.5256

The yields of various groups of α-particles have been measured for E_d ≤ 20 MeV: see (1978AJ03, 1983AJ01). The yield curves have been fitted in terms of a large number of states in ¹⁸F: see Tables 18.17 (in PDF or PS) here, and 18.16 (in PDF or PS) in (1978AJ03).

A detailed study by (1973JO13) of the isospin-forbidden α₁ yield, analyzed by S-matrix theory, identifies a large number of isospin mixed states in ¹⁸F, possibly as many as 138 with 9.2 < E_x < 19.4 MeV. The reaction mechanism appears to be almost entirely compound nuclear. The isospin impurity, averaged over 1 MeV intervals, is 3 - 10% for the above E_x range. The average coherence width increases from ≈ 100 keV at E_x = 14 MeV to ≈ 500 keV at E_x = 20 MeV. The level densities appear to be consistent with predictions of the Fermi-gas model (1973JO13). See also (1985JOZZ). [For mixed isospin states observed in ¹⁴N(α, α₁) see Table 18.14 (in PDF or PS) in (1978AJ03).] Polarization measurements are reported for E_d = 6.8 to 16 MeV: see (1978AJ03, 1983AJ01).

19. ¹⁶O(d, ⁶Li)¹²C Q_m = -5.6868 E_b = 7.5256

Polarization measurements for the transitions to ¹²C*(0, 4.4) are reported at E_{pol. d} = 18 and 22 MeV (1987TA07; VAP, TAP) and 51.7 MeV (1986YA12; VAP; also to ¹²C*(14.1)).

20. ¹⁶O(t, n)¹⁸F Q_m = 1.2690

See (1987BO16; applied) and (1983AJ01).

21. ¹⁶O(³He, p)¹⁸F Q_m = 0.321

Excitation energies derived from measurements of γ-rays are displayed in Table 18.18 (in PDF or PS) together with l-assignments obtained from distorted-wave analyses, and J^π; T and K^π assignments from branching ratios, radiative widths, linear polarization, γ-ray angular distributions and τ_m measurements [see also Tables 18.14 (in PDF or PS) and 18.15 (in PDF or PS)]. Studies of this reaction, together with the work on ¹⁴N(α, γ) and ¹⁷O(p, γ), have defined the low-lying states of ¹⁸F.

The g-factor of ¹⁸F*(0.94) [J^π = 3⁺] is +(0.56 ± 0.05): see (1983AJ01). The circular polarization of the 1.08 MeV → g.s. γ-ray, P_γ = (-10 ± 18) × 10^-4 (1982AH07), (2.7 ± 5.7) × 10^-4 (1985BI03), (1.6 ± 5.6) × 10^-4 (1985EV03), (1.7 ± 5.8) × 10^-4 (1987PA07). The weak pion-nucleon coupling constant deduced from the weighted average of all recent P_γ measurements [(1.2 ± 3.9) × 10^-4] is (0.3^+1.0_-0.3) × 10^-7. Together with PNC matrix elements in other experiments this suggests that the isovector weak NN interaction may be strongly suppressed compared with the isoscalar weak NN interaction (1985EV03, 1987PA07). For a measurement of the ICC of the 0.94, 1.02, 1.04 and 1.08 MeV γ-rays see (1986KR04). See also (1978AJ03, 1983AJ01), (1984BE1A; applications), (1987ER05; theor.) and ¹⁹Ne.

22. ¹⁶O(α, d)¹⁸F Q_m = -16.3211

Angular distributions of the deuteron groups to ¹⁸F*(1.12) [J^π = 5⁺] have been studied at E_α = 28.0 to 33.6 MeV: see (1983AJ01). At E_α = 65.3 MeV a number of angular distributions are reported to ¹⁸F states with E_x ≤ 11.4 MeV: ¹⁸F*(9.49, 10.54) are suggested to have J^π = 6^- and 7⁺ respectively (1986KA36). See, however, reactions 9 and 10.

23. ¹⁶O(⁶Li, α)¹⁸F Q_m = 6.050

Angular distributions have been measured at E(⁶Li) = 5.5 to 34 MeV [see (1983AJ01)] and at E(⁶Li) = 48 MeV (1984CO05; α₀, α₁, α₄). (1982FR15) report the excitation of a state at E_x = 4848.3 ± 0.5 keV which decays (35 ± 4)% to ¹⁸F*(3.79) [E_γ = 1056.8 ± 0.4 keV] and (65 ± 4)% to ¹⁸F*(1.12). Alpha-γ angular correlations are consistent with J^π = 5^-, and T = 0 (1982FR05). See also (1986BGL02) and (1986IC01; theor.).

24. (a) ¹⁶O(¹¹B, ⁹Be)¹⁸F Q_m = -8.290
(b) ¹⁶O(¹³C, ¹¹B)¹⁸F Q_m = -11.153
(c) ¹⁶O(¹⁴N, ¹²C)¹⁸F Q_m = -2.7468

See (1983AJ01).

25. ¹⁷O(p, γ)¹⁸F Q_m = 5.6065

Gamma-ray measurements lead to the very accurate E_x determinations for ¹⁸F states below 6.2 MeV: see Table 18.19 (in PDF or PS). Observed resonances are displayed in Table 18.20 (in PDF or PS); branching ratios, radiative widths and multipole mixing ratios are shown in Table 18.14 (in PDF or PS); and τ_m in Table 18.15 (in PDF or PS).

The direct capture cross section has been studied for E_p = 0.3 to 1.9 MeV: ¹⁸F*(5.603, 5.605, 5.668, 5.786) have J^π = 1⁺, 1^-, 1^- and 2^-. The 1^- states have mixed isospin. For astrophysical considerations see (1978AJ03, 1983AJ01) and (1982RO1A).

26. ¹⁷O(p, n)¹⁷F Q_m = -3.5432 E_b = 5.6065

Observed resonances are displayed in Table 18.20 (in PDF or PS). Analyzing power measurements are reported at E_{pol. p} = 135 MeV (1983PUZZ; n₀).

27. ¹⁷O(p, p)¹⁷O E_b = 5.6065

The elastic scattering has been studied for E_p = 0.5 to 13 MeV [see (1978AJ03, 1983AJ01)]: observed anomalies are displayed in Table 18.20 (in PDF or PS). Analyzing powers have been measured at E_{pol. p} = 89.7 MeV (1985VO12; p₀).

28. ¹⁷O(p, t)¹⁵O Q_m = -11.3257 E_b = 5.6065

Analyzing powers have been reported at E_{pol. p} = 89.7 MeV for the triton groups to a number of ¹⁵O states (1985VO12).

29. ¹⁷O(p, α)¹⁴N Q_m = 1.1914 E_b = 5.6065

The yield of α₀ shows a number of resonances for E_p = 0.49 to 3.0 MeV: see Table 18.20 (in PDF or PS). The R-matrix fit of (1979KI13), obtained from data from E_p = 400 to 1400 keV, confirms the earlier result [see, e.g., (reaction 31 in (1978AJ03))] that a significant quantity of ¹⁷O is burned up in the (p, γ) rather than in the (p, α) reaction for a wide range of stellar temperatures (1979KI13). See also (1982RO1A, 1987RO25) and (1986BA89; theor.).

30. ¹⁷O(³He, d)¹⁸F Q_m = 0.1130

At E(³He) = 15 MeV DWBA analysis of angular distributions of deuteron groups corresponding to states of ¹⁸F with E_x < 5 MeV have led to J^π values and spectroscopic information: see (1972AJ02). See also (1987ER05; theor.).

31. ¹⁷O(¹²C, ¹¹B)¹⁸F Q_m = -10.351

See (1983AJ01).

32. ¹⁸O(π⁺, π⁰)¹⁸F Q_m = 2.949

See (1983AS01, 1984AS05).

33. ¹⁸O(p, n)¹⁸F Q_m = -2.4387

(1983AN05) have studied the distribution of Gamow-Teller (GT) strength. At E_p = 135 MeV angular distributions have been studied to the 0⁺ state at 1.04 MeV and to the 1⁺ states ¹⁸F*(0, 1.70, 3.72, 4.36, 6.26) as well as to possible 1⁺; T = 1 groups at E_x = 9.9 10.9 and 11.9 MeV. 82% of the observed strength lies in the ground state group and 5.5% in the (T = 1) states. The observed GT strength is ≈ 2/3 of that expected from the simple sum rule (1983AN05). See also (1985TAZY), (1985WA24), (1986MA1P, 1987HI1B; applied) and the earlier work in (1978AJ03).

34. ¹⁸O(³He, t)¹⁸F Q_m = -1.675

At E(³He) = 16 MeV, the triton spectrum is dominated by strong groups to ¹⁸F*(0, 0.94) and to the 0⁺ and 2⁺, T = 1 states ¹⁸F*(1.04, 3.06). Angular distributions have been studied to these and many other states at this energy and at E(³He) = 17.3 MeV. At E(pol. ³He) = 33 MeV A_y measurements for t₀ have been reported. See (1983AJ01) for references.

35. ¹⁸O(⁶Li, ⁶He)¹⁸F Q_m = -5.162

See (1978AJ03).

36. ¹⁸Ne(β⁺)¹⁸F Q_m = 4.446

The half-life of ¹⁸Ne is 1672 ± 8 msec [see ¹⁸Ne]. The decay is to ¹⁸F*(0, 1.04, 1.08, 1.70): see Table 18.21 (in PDF or PS).

37. ¹⁹F(γ, n)¹⁸F Q_m = -10.4320

Cross sections have been reported to 30 MeV for the transitions to ¹⁸F*(0.94, 1.04, 1.08, 3.06, 3.13, 4.75): see (1983AJ01).

38. ¹⁹F(p, d)¹⁸F Q_m = -8.2074

Angular distributions have been reported to many states of ¹⁸F with E_x ≲ 6 MeV: see Table 18.20 (in PDF or PS) in (1983AJ01). See also (1986VAZV [E_p = 18.6 MeV; d₀, d₂]), (1983BEYY) and (1981CL05, 1983KI13; theor.).

39. ¹⁹F(d, t)¹⁸F Q_m = -4.1747

See (1972AJ02, 1978AJ03).

40. ¹⁹F(³He, α)¹⁸F Q_m = 10.1458

See (1978AJ03).

41. ²⁰Ne(p, ³He)¹⁸F Q_m = -15.562

See (1978AJ03).

42. ²⁰Ne(d, α)¹⁸F Q_m = 2.7915

At E_d = 11 MeV α-groups are observed to many states of ¹⁸F with E_x < 7 MeV. Weak or absent (each ≤ 0.3% of the total yield at 30°) are the groups corresponding to ¹⁸F*(1.04, 3.06, 4.66, 4.74, 4.96): T = 1. Measurements of the TAP for E_{pol. d} = 10.25 to 12.0 MeV leads to assignments of 2^-, 1⁺, 0⁺, 1^-, 1⁺, 3⁺, 3⁺ to ¹⁸F*(4.23, 4.36, 4.75, 4.86, 5.603, 6.16, 6.48). See (1972AJ02, 1978AJ03, 1983AJ01) for references and for other results and (1987HI1B; applications).

43. ²¹Ne(p, α)¹⁸F Q_m = -1.744

See (1987GOZX).

44. ²³Na(d, ⁷Li)¹⁸F Q_m = -12.176

See (1984NE1A).