A=16O (1977AJ02)

The mass of ¹⁶O derived from the work of (1975SM02) is 15.994914616 (22) a.m.u. Using the conversion factor 931.5016 (26) MeV/a.m.u., the mass excess of ¹⁶O would then be -4737.04 ± 0.02 keV. (1971WA37) quotes -4736.68 ± 0.19 keV which we shall continue to assume. See also (1971SM01).

< r² >^1/2 = 2.71 ± 0.02 fm (1974DU02),

< r² >^1/2 = 2.718 ± 0.021 fm (1973FE13, 1975SC18).

|g| = 0.55 ± 0.03 for ¹⁶O*(6.13) (1973BR31, 1973RA09). See also (1976KA1N).

1. (a) ¹⁰B(⁶Li, p)¹⁵N Q_m = 18.749 E_b = 30.877
(b) ¹⁰B(⁶Li, d)¹⁴N Q_m = 10.140
(c) ¹⁰B(⁶Li, t)¹³N Q_m = 5.844
(d) ¹⁰B(⁶Li, ³He)¹³C Q_m = 8.8083
(e) ¹⁰B(⁶Li, α)¹²C Q_m = 23.715

At E(⁶Li) = 4.9 MeV, the cross sections for reactions (a) to (e) leading to low-lying states in the residual nuclei are proportional to 2J_f+1: this is interpreted as indicating that the reactions proceed via a statistical compound nucleus mechanism. For highly excited states, the cross section is higher than would be predicted by a 2J_f+1 dependence (1966MC05). The yield curves for α₀ and α₁ (reaction (e)) measured at 0° for E(⁶Li) = 3.2 to 13.6 MeV show broad structures. At 90°, for E(⁶Li) = 9.7 to 13.0 MeV no structure is apparent, suggesting that the 0° yield is explainable in terms of Ericson fluctuations (1967SE08).

2. ¹⁰B(¹⁰B, α)¹⁶O Q_m = 26.417

States of ¹⁶O observed at E(¹⁰B) = 20 MeV are displayed in Table 16.10 (in PDF or PS). The reaction excites known T = 0 states: σ_t follows 2J_f+1 for 11 of 12 groups leading to states of known J. The angular distributions show little structure (1976AJ02).

3. ¹⁰B(¹⁴N, ⁸Be)¹⁶O Q_m = 14.711

See (1971AJ02).

4. ¹¹B(⁷Li, 2n)¹⁶O Q_m = 12.170

See (1971AJ02).

5. ¹²C(α, γ)¹⁶O Q_m = 7.1616

The yield of capture γ-rays has been studied for E_α < 27.5 MeV: see Table 16.11 (in PDF or PS). Observed resonances are displayed in Table 16.12 (in PDF or PS).

This reaction plays an important role in astrophysical processes. (1974DY02) has determined σ_E1 for E_α = 1.88 to 3.92 MeV. From these data S(E_α(lab) = 400 keV) = 0.08^+0.05_-0.04 MeV · b (1974KO06) [used a hybrid R-matrix-optical model analysis (α, γ) and (α, α)], 0.08^+0.14_-0.07 MeV · b (1976HU1H) [used a two channel, two level approximation of a modified K-matrix]. See also (1971BA99, 1974WE14). (1974DY02) state that S depends quite strongly on θ²_α(6.92)/θ²_α(7.12): S may have to be increased to allow for the tail of ¹⁶O*(6.92). For astrophysical considerations see (1974DY02) and (1971BA1A, 1971BI1H, 1973AR1E, 1973CL1E, 1973IB1B, 1974BA1X, 1975FO19, 1976AU1F, 1976SC1M), in addition to the references listed above and in (1971AJ02).

Upper limits of the parity forbidden α-decay of ¹⁶O*(10.95, 11.08) [J^π = 0^-; T = 0 and 3⁺; 0, respectively] are < 6 × 10^-4 eV and < 5 × 10^-4 eV, respectively (1974BE32). See also (1974DA22) and (1973GA23; theor.).

At higher energies the E2 cross section shows resonances at E_x = 13.2, 15.9, 16.5, 18.3, 20.0 and 26.5 MeV [see Table 16.12 (in PDF or PS)]. Some E2 strength is also observed for E_x = 14 to 15.5 and 20.5 to 23 MeV. In the range E_α = 7 to 27.5 MeV the T = 0 E2 strength is ≈ 17% of the sum rule. It appears from this and other experiments that the E2 centroid is at E_x ≈ 15 MeV, with a 15 MeV spread (1974SN02). See also (1969OM1A), (1973HA1Q, 1973HA1Y), (1975RA02; theor.) and (1971AJ02) for the earlier work.

6. ¹²C(α, n)¹⁵O Q_m = -8.508 E_b = 7.1616

Cross section measurements have been made from threshold to E_α = 24.7 MeV: see (1971AJ02) and Table 16.11 (in PDF or PS). Observed resonances are displayed in Table 16.12 (in PDF or PS). The resonance in n₀ at E_α = 14.6 MeV (¹⁶O*(18.1)) does not appear in the p₀ yield: a large isospin mixing is suggested for that state (1971BE07). An anomaly is observed in the n₀ yield corresponding to formation of the first T = 2 state in ¹⁶O [¹⁶O*(22.7)] (1973AD1B). See also ¹⁵O in (1976AJ04).

7. ¹²C(α, p)¹⁵N Q_m = -4.9661 E_b = 7.1616

The yield of protons corresponding to ¹⁵N(0) has been studied for E_α = 7.7 to 23 MeV: see Table 16.10 (in PDF or PS) in (1971AJ02) and Table 16.11 (in PDF or PS) here. (1975SP04) have measured the yield of 10.6 MeV γ-rays [from ¹⁵N*(10.45 → 10.80)] at E_α = 22.8 to 27 MeV. Observed resonances are displayed in Table 16.12 (in PDF or PS). An anomaly is observed in the p₀ yield corresponding to formation of the T = 2 state ¹⁶O*(22.7): see (1973AD1B) and (1972WE03). See also ¹⁵N in (1976AJ04).

8. ¹²C(α, d)¹⁴N Q_m = -13.5751 E_b = 7.1616

See ¹⁴N in (1976AJ04) and (1974BE41).

9. (a) ¹²C(α, t)¹³N Q_m = -17.871 E_b = 7.1616
(b) ¹²C(α, ³He)¹³C Q_m = -15.6321

See ¹³N and ¹³C in (1976AJ04) and (1974BE41).

10. ¹²C(α, α)¹²C E_b = 7.1616

The yield of α-particles corresponding to ¹²C*(0, 4.4) and of 4.4, 12.7 and 15.1 MeV γ-rays has been studied at many energies in the range 2.5 to 35.5 MeV: see Table 16.11 (in PDF or PS). Observed resonances are displayed in Table 16.12 (in PDF or PS). The parameters of the first T = 2 state of ¹⁶O at E_x = 22.7 MeV observed as anomalies in the α₀ and α₂ yields are displayed in Table 16.12 (in PDF or PS) (1972NE10). Astrophsyical considerations are discussed in reaction 5. See also (1971LE33, 1974KO06, 1974WE14, 1975ME1E, 1975ST1K, 1976GL1D, 1976HU1H).

For angular correlation measurements see (1972BU09, 1972KE18). For differential cross section measurements at E_α = 58 MeV see (1974BE41). For polarization parameters see (1972BU09). For τ⁰ emission at E_α = 710 MeV see (1976WA1P). For spallation measurements see (1971FO06, 1971LE33, 1972RU03, 1974GA1K, 1974RA11, 1975FU01, 1975RA12).

11. (a) ¹²C(α, ⁸Be)⁸Be Q_m = -7.4587 E_b = 7.1616
(b) ¹²C(α, 2α)⁸Be Q_m = -7.3667
(c) ¹²C(α, 4α) Q_m = -7.2748

The yield of ⁸Be (reaction (a)) shows a number of resonances: see Table 16.12 (in PDF or PS). There is no evidence below E_x ≈ 24 MeV for J^π = 8⁺ states although the existence of such states below this energy cannot be ruled out since it is possible that the L of the entrance channel inhibits the formation of such states. Above 26 MeV L = 8 becomes dominant (1976BR07). See also (1972SU04; theor.) and (1971AJ02). For reaction (b) see (1975CO1C). For reaction (c) see (1970KL10, 1973RU09). See also ¹²C in (1975AJ02) and ⁸Be in (1974AJ01).

12. ¹²C(⁶Li, d)¹⁶O Q_m = 5.6879

This reaction has been studied at many energies for E(⁶Li) < 42 MeV and E(¹²C) = 18 to 24 MeV: see Table 16.13 (in PDF or PS) in (1971AJ02). Angular distributions are also reported at E(⁶Li) = 32 MeV [(1974DE16: to ¹⁶O*(10.35, 11.10)), (1972BA2B: to ¹⁶O*(10.35))], at 32.5 and 35.5 MeV (1975GO15: to ¹⁶O*(10.35, 14.6, 16.3, 20.9)) and at 42 MeV (1976JAZV; to most states with E_x < 16 MeV). At the higher energies the spectra are dominated by states with J ≥ 4 (and natural parity). Among these are states with E_x = 10.346 ± 0.006, 16.304 ± 0.020 and 20.88 ± 0.06 MeV [Γ_cm < 50, 360 ± 40 and 720 ± 100 keV] and J^π = 4⁺, (6⁺), (8⁺) (1971BA31). Angular correlation (d, α₀) measurements agree with the 6⁺ assignment for ¹⁶O*(16.3) [Γ_cm = 370 ± 50 keV] (1971AR30, 1971AR36) but show that ¹⁶O*(20.9) [Γ_cm = 590 ± 100 keV] is a 7^- state (1971AR30, 1971AR36, 1975AV02). A state at E_x = 21.8 MeV is reported by (1975AV02): J = 6. Angular correlations also suggest J^π = 5^- for a state with E_x = 14.6 ± 0.1 MeV, Γ_cm = 480 ± 100 keV (1971AR36, 1974AR24): the branching ratios for the decay of ¹⁶O*(14.6, 16.3, 20.9) to ¹²C_g.s. is 85 ± 10, 80 ± 10 and 90 ± 10 %, respectively (1971AR30, 1971AR36, 1974AR24).

At E(⁶Li) = 32 MeV the σ(11.10)/σ(10.35) ≈ 0.5 even though the ratio of the reduced widths of these two 4⁺ states to ¹²C_g.s. S_α(11.10)/S_α(10.35) < 10^-2: a two step process via ¹²C*(4.4) is suggested (1974DE16)^†. θ²_α for all ¹⁶O states with E_x < 10.4 MeV are listed in (1967LO01). See also (1976JAZV). Gamma-ray angular distribution measurements have been carried out at E(⁶Li) = 4.5 to 6.5 MeV (1972CA14, 1972ZA08). For angular correlation measurements, see (1973BA53, 1976BAYO) and ¹⁸F in (1978AJ03).

^† However, compound nuclear effects may account for this ratio (F. Becchetti, private communication).

13. ¹²C(⁷Li, t)¹⁶O Q_m = 4.695

This reaction has been studied at many energies for E(⁷Li) < 38 MeV: see Table 16.13 (in PDF or PS) in (1971AJ02) and (1971BA2Q, 1971BA2R: E(⁷Li) = 32 MeV) and (1976CO23: E(⁷Li) = 38 MeV). In the latter work the spcetra at forward angles are dominated by members of the 4p-4h K^π = 0⁺ band [¹⁶O*(6.05, 6.92, 10.35, 16.3): J^π = 0⁺, 2⁺, 4⁺, 6⁺] and by those of the K^π = 0^- band [¹⁶O*(9.63, 11.60, 14.67, 20.9): J^π = 1^-, 3^-, (5^-), 7^-]. Hauser-Feshbach calculations have been made for many of the ¹⁶O states and, in particular, for a state at E_x = 14.363 ± 15 keV which is not resolved at forward angles. The width of this state is < 120 keV and J > 5, π = natural (1976CO23; M.E. Cobern, private communication). See also (1971LA1B, 1972CA1E), (1971BA2V, 1972GA1E, 1973FO1E, 1973FO1A, 1973OG1A, 1974ST1L, 1975GO15) and (1970DO13, 1972KU12, 1973IC01, 1974DO03, 1975PA11; theor.).

14. ¹²C(¹⁰B, ⁶Li)¹⁶O Q_m = 2.701

At E(¹⁰B) = 18 and 45 MeV angular distributions have been studied involving ¹⁶O*(0, 6.1, 7.1, 8.9, 9.9, 10.4): this reaction does not appear to select special states of ¹⁶O (1970HI08). See (1970JA1B, 1973YO1C). See also (1972GA1E) and (1973KU03, 1974NE18; theor.).

15. ¹²C(¹¹B, ⁷Li)¹⁶O Q_m = -1.504

At E(¹¹B) = 110 MeV, the population of ¹⁶O*(6.05, 6.92, 10.35, 16.3) is particularly strong (1975PI1C). See also (1970RO23), (1973SC1J) and (1973ST1D; theor.).

16. ¹²C(¹²C, ⁸Be)¹⁶O Q_m = -0.205

Angular distributions have been measured at E(¹²C) = 42 MeV (1976AR02: ⁸Be_g.s. + ¹⁶O*(0, 6.1, 6.9, 10.4)), 60 → 63 MeV (1973CR1A, 1976MA12, 1976WE04: ⁸Be_g.s.+¹⁶O*(0, 6.1, 6.9, 10.4, 11.1, 14.7, 16.3)), and also for the ground state transitions at E(¹²C) = 11.6 to 13.4 MeV (1972CO1H), 18 to 40 MeV (1976FL05) and 37 MeV (1975EB03, 1976EB01). Angular correlations at E(¹²C) = 78 MeV confirm J^π = 4⁺, 5^-, 6⁺ and 7^- for ¹⁶O*(10.35, 14.67, 16.29, 20.88) (1976SAZE; and P.D. Parker, private communication: ⁸Be(0°), α₀). At the latter energy l = 12 seems dominant: for yield measurements see ²⁴Mg in (1978EN06). See also (1972PA1G, 1972WO10, 1974HO30, 1975PI1C), (1972GA1E, 1973FO1E, 1973SC1J, 1974ST1L) and reaction 13 in (1971AJ02).

17. ¹²C(¹⁴N, ¹⁰B)¹⁶O Q_m = -4.452

See (1975ZE1C). See also (1975NA1L) and (1973SC1J).

18. (a) ¹²C(¹⁶O, ¹²C)¹⁶O
(b) ¹²C(¹⁸O, ¹⁴C)¹⁶O Q_m = 0.934

For reaction (a) see reaction 72. For reaction (b) see (1974CH1Q, 1976WE05) [see ³⁰Si in (1978EN06)], (1974GO1L), (1970AN1D, 1971AL1D, 1971RO1G, 1972RO35, 1975TA02, 1976KA04; theor.) and reaction 15 in (1971AJ02).

19. ¹²C(¹⁹F, ¹⁵N)¹⁶O Q_m = 3.149

Angular distributions have been measured at E(¹⁹F) = 40, 60 and 68.8 MeV involving different states in ¹⁵N and ¹⁶O*(0, 6.1, 7.0, 10.4) (1972SC17). See also (1970VO1F, 1975PU02), (1972GA1E, 1972MO1E, 1973SC1J) and (1972BO21; theor.).

20. ¹²C(²⁰Ne, ¹⁶O)¹⁶O Q_m = 2.4304

At E(²⁰Ne) = 108 and 147 MeV the spectrum involves groups at E_x = 6.1 (u), 7.0 (u), 10.3, 11.1, 14.6 (u) and 16.2 MeV [u = unresolved] (1974ME27, 1975PI1C). Angular distributions are reported at E(²⁰Ne) = 78 MeV to E_x = 6.1 (u), 6.9 (u), 8.9 and 10.4 MeV (1970RO23). See also ³²S in (1978EN06) and (1975DO06). See also (1972GA1E).

21. ¹³C(³He, γ)¹⁶O Q_m = 22.7937

The yield of γ₀ has been studied for E(³He) = 3 to 8 MeV (1972VE1A; abstract) and 3 to 16 MeV (1974SH01). In the latter experiments the γ_1+2+3+4 yield has also been measured as have many angular distributions: the 90° γ₀ yield is characterized by resonances at E(³He) ≈ 4 and ≈ 6 MeV, the γ_1+2+3+4 yield by a single broad structure at ≈ 5.5 MeV. The peak cross section for the latter yield is an order of magnitude greater than the cross sections for the peaks observed in the γ₀ yield (1974SH01). The yield of (γ₁ + γ₂) [E(³He) = 3.9 to 12 MeV] shows one resonance at E(³He) = 4.5 MeV (1974CH37): see Table 16.13 (in PDF or PS) [also measured the (γ₃ + γ₄) yield in the range 3.9 to 8.7 MeV]. For the earlier work see (1966PU01). See also (1973SU1E) and reaction 46.

22. ¹³C(³He, n)¹⁵O Q_m = 7.124 E_b = 22.7937

The excitation functions to E(³He) = 11 MeV [see Table 16.14 (in PDF or PS) of (1971AJ02) and (1972ET01: E(³He) = 4.0 → 5.8 MeV for n to ¹⁵O*(0, 6.18, 7.28, 7.56))] are marked at low energies by complex structures and possibly by two resonances at E(³He) = 1.55 and 2.0 MeV: see Table 16.13 (in PDF or PS). Polarization measurements for the n₀ group have been reported at E(³He) = 3.0 to 5.7 MeV [see (1971AJ02)] and at E(³He) = 12, 16 and 20 MeV (1973RH1A; abstract). See also ¹⁵O in (1976AJ04).

23. ¹³C(³He, p)¹⁵N Q_m = 10.6659 E_b = 22.7937

The yield curves for p₀ and p₁₊₂ for E(³He) = 4.0 to 8.0 MeV show a resonance at 6 MeV (1968WE15, 1968WE1C): see Table 16.13 (in PDF or PS). (1972ST22) have measured excitation functions for E(³He) = 3.5 to 6 MeV for the p₀, p₁₊₂, p₃ → p₆ groups: some uncorrelated structures are observed. See also ¹⁵N in (1976AJ04).

24. ¹³C(³He, d)¹⁴N Q_m = 2.0569 E_b = 22.7937

See ¹⁴N in (1976AJ04).

25. ¹³C(³He, t)¹³N Q_m = -2.239 E_b = 22.7937

The excitation function for formation of ¹³N_g.s. has been studied for E(³He) = 11 to 17 MeV (1970NU02). See also ¹³N in (1976AJ04).

26. ¹³C(³He, ³He)¹³C E_b = 22.7937

See (1967WE06, 1968WE15, 1968WE1C) and Table 16.13 (in PDF or PS).

27. ¹³C(³He, α)¹²C Q_m = 15.6321 E_b = 22.7937

Yields of α₀, α₁, α₂ and γ-rays from decay of ¹²C*(12.71, 15.11) have been studied up to E(³He) = 12 MeV: see Table 16.14 (in PDF or PS) in (1971AJ02) and (1971BO26: E(³He) = 1.2 to 5.4 MeV; α₀, α₁, α₂). Observed resonances are displayed in Table 16.13 (in PDF or PS). Those seen in the yield of γ_15.1 are assumed to correspond to ¹⁶O states which have primarily a T = 1 character. See (1971AJ02) for a summary of the earlier references and ¹²C in (1975AJ02).

28. ¹³C(³He, ⁸Be)⁸Be Q_m = 8.173 E_b = 22.7937

The excitation function for ⁸Be_g.s. has been studied for E(³He) = 2 to 6 MeV. It shows a strong resonance at E(³He) = 5.6 MeV corresponding to a state in ¹⁶O at E_x = 27.3 MeV. J^π appears to be 2⁺ from angular distribution measurements (1968JA07).

29. ¹³C(α, n)¹⁶O Q_m = 2.2152

Angular distributions for the n₀ group have been measured for E_α = 12.8 to 22.5 MeV: see (1971AJ02). ¹⁶O*(6.05) has been observed as a neutron threshold (1956BO61). See also ¹⁷O, (1970CL1C, 1973CL1E, 1973TR1B; astrophys. considerations) and (1971TE10; theor.).

30. ¹³C(⁶Li, t)¹⁶O Q_m = 6.999

Angular distributions have been studied at E(⁶Li) = 20 and 28 MeV to ¹⁶O*(0 [at 28 MeV], 6.13, 7.0, 8.87, 9.85, 10.35, 11.09). At these energies the spectra are dominated by the triton groups to ¹⁶O*(11.09, 14.30, 14.39, 14.82). At E(⁶Li) = 25 MeV the excitation of ¹⁶O*(14.52, 14.66) is also reported (1969BA50, 1971BA2Q, 1971BA2R, 1971DE1X, 1972BA2B). See also (1971BA2V).

31. ¹³C(¹²C, ⁹Be)¹⁶O Q_m = -3.486

At E(¹²C) = 87 MeV, angular distributions are reported for transitions to ¹⁶O*(6.9, 8.9, 10.4, 11.1, 13.5, 14.8, 15.1, 16.1, 16.5) (1970RO23). The ground state angular distribution has also been studied at E(¹³C) = 36 MeV (1976WE21).

32. ¹³C(¹⁷O, ¹⁴C)¹⁶O Q_m = 4.032

See (1974CH1Q).

33. ¹⁴C(³He, n)¹⁶O Q_m = 14.6167

At E(³He) = 11 to 16 MeV, neutron groups are observed to T = 2 states at E_x = 22.717 ± 0.008 and 24.522 ± 0.011 MeV (Γ < 30 keV and < 50 keV, respectively). These two states are presumably the first two T = 2 states in ¹⁶O, the analog states to ¹⁶C*(0, 1.75). J^π for ¹⁶O*(24.52) is found to be 2⁺ from angular distribution measurements (1970AD01). Angular distributions are also reported at E(³He) = 2.1 to 3.4 MeV and at 6 MeV: see (1971AJ02). See also (1974MA1M, 1975CE1D).

34. ¹⁴C(¹⁸O, ¹⁶C)¹⁶O Q_m = -6.719

See ¹⁶C, reaction 4.

35. ¹⁴N(d, γ)¹⁶O Q_m = 20.7368

The γ₀ yield has been studied for E_d = 0.5 to 5.5 MeV (1966SU05, 1966SU1C) and 2.1 to 2.9 MeV (1972WE04). The yield shows a resonance at E_d = 2.40 ± 0.05 MeV, Γ_cm ≈ 0.6 MeV (1972WE04, 1974DA30). The angular distribution of γ₀ at resonance is consistent with E1: J^π = 1^-; T = 1: it may be the Gillet 2p-2h quasibound state: see, however, reaction 46. Structures at E_x = 22.2 and 24.5 MeV are also reported (1966SU05): see Table 16.14 (in PDF or PS). See also (1971AJ02), (1973SU1E) and (1973JA1E; theor.).

36. ¹⁴N(d, n)¹⁵O Q_m = 5.067 E_b = 20.7368

For E_d = 0.66 to 5.62 MeV, there is a great deal of resonance structure in the excitation curves with the anomalies appearing at different energies at different angles: the more prominent structures in the yield curves are displayed in Table 16.14 (in PDF or PS) (1960RE07, 1965BU1A). Yield measurements are also reported for E_d = 2.9 to 5.0 MeV (1970RI01: n₂, n₃, n₄, n₆, n₇). For polarization measurements see Table 16.16 (in PDF or PS) in (1971AJ02) and (1976LI1R: 4.5 to 15 MeV: n₁₊₂), (1972FO07: 5.16 MeV; n₀, n₁₊₂, n₃, n₄₊₅, n₆, n₇) and (1971HI09: 10.0 and 11.8 MeV; n₀). See also (1969WO09, 1971WA1D, 1974LO1B), (1970ME25; theor.) and ¹⁵O in (1976AJ04).

37. ¹⁴N(d, p)¹⁵N Q_m = 8.6090 E_b = 20.7368

The yield curves of various proton groups show a great deal of structure: see reaction 30 and Table 16.16 (in PDF or PS) in (1971AJ02) for a summary of the earlier work. Resonant structure reported by (1962GO21, 1972NE10) is displayed in Table 16.14 (in PDF or PS). For polarization measurements see Table 16.16 (in PDF or PS) in (1971AJ02), (1976PA1K; 11.8 MeV, p₀) and (1971EG01; 13.8 MeV; p₀). See also (1974DA13), (1974LO1B), (1972KO30; theor.) and ¹⁵N in (1976AJ04).

38. ¹⁴N(d, d)¹⁴N E_b = 20.7368

The yield of elastically scattered deuterons has been studied for E_d = 0.65 to 5.5 MeV [see Table 16.16 (in PDF or PS) in (1971AJ02)] and for 14.0 to 15.52 MeV (1974BU06). (1967FL10) report a number of resonances in the d₀ yield corresponding to states in ¹⁶O with 22.6 ≤ E_x ≤ 25.2 MeV. There is indication of broad structure at E_d = 5.9 MeV and of sharp structure at E_d = 7.7 MeV in the total cross section of the d₁ group to the T = 1 (isospin-forbidden), J^π = 0⁺ state at E_x = 2.31 MeV in ¹⁴N. The yield of deuterons (d₂) to ¹⁴N*(3.95) [J^π = 1⁺; T = 0] shows gross structures at E_d = 7.4 and 10.2 MeV (1970DU04): see Table 16.14 (in PDF or PS). Polarization measurements involving the elastic group are reported at E_d = 11.6 MeV (1973BR15) and 15 MeV (1973DA26, 1974BU06). See also ¹⁴N in (1976AJ04) and (1970ME25, 1974FA1A; theor.).

39. (a) ¹⁴N(d, t)¹³N Q_m = -4.296 E_b = 20.7368
(b) ¹⁴N(d, ³He)¹³C Q_m = -2.0569

Polarization measurements have been carried out at E_d = 15 MeV for the groups to ¹³C_g.s. and ¹³N_g.s. (1973DA26, 1974LU06). See also ¹³C and ¹³N in (1976AJ04).

40. ¹⁴N(d, α)¹²C Q_m = 13.5751 E_b = 20.7368

There is a great deal of structure in the yields of various α-particle groups for E_d = 0.5 to 12 MeV: see Table 16.16 (in PDF or PS) in (1971AJ02) for the earlier work. The more prominent structures are shown in Table 16.14 (in PDF or PS) (1961IS03, 1962IS02, 1967LA16, 1972NE10). The yield of 15.11 MeV γ-rays [from the decay of ¹²C*(15.11), J^π = 1⁺; T = 1] which is isospin-forbidden has been studied for E_d = 2.8 to 12 MeV. Pronounced resonances are observed at E_d = 4.2, 4.58 and 5.95 MeV and broader peaks occur at E_d = 7.1 and, possibly, at 8.5 MeV (see Table 16.14 (in PDF or PS)). Above E_d = 9.5 MeV, the yield curve is quite featureless (1965BR08). See also ¹²C in (1975AJ02). Polarization measurements have been carried out at E_d = 15 MeV (1976LU1A; α₀, α₁, (α₂)).

41. (a) ¹⁴N(t, n)¹⁶O Q_m = 14.4792
(b) ¹⁴N(t, np)¹⁵N Q_m = 2.351
(c) ¹⁴N(t, nα)¹²C Q_m = 7.318

At E_t = 2.2 to 2.6 MeV, the two-stage reaction (b) proceeds via ¹⁶O*(14.92, 16.22) (1961JA14) while reaction (c) proceeds via ¹⁶O*(13.10, 15.45) (1962SI04).

42. (a) ¹⁴N(³He, p)¹⁶O Q_m = 15.2430
(b) ¹⁴N(³He, pα)¹²C Q_m = 8.0814

Observed proton groups are displayed in Table 16.16 (in PDF or PS) (1964BR08). Angular distributions have been measured at E(³He) = 2.5 to 18 MeV: see (1971AJ02), (1972BI01: E(³He) = 7.96 → 18.0 MeV), (1971GU22: E(³He) = 9 MeV) and (1971WE16: 18 MeV). Analysis by DWBA is satisfactory for ¹⁶O*(6.13, 7.12, 8.87, 10.95). ¹⁶O*(6.05, 6.92, 10.35) are very weakly populated in accord with their presumed 4p-4h character. It is suggested that the 2p-2h strength lies mainly above E_x = 14 MeV (1971WE16). Branching ratios (shown in Table 16.15 (in PDF or PS)) and pγ correlation measurements lead to J^π = 2^-, 0^- and 3⁺ for ¹⁶O*(8.87, 10.95, 11.08) (1959BR68, 1959KU78); τ_m are shown in Table 16.21 (in PDF or PS).

At E(³He) = 8 MeV a study of the protons in coincidence with 4.4 MeV γ-rays (reaction (b)) indicates that the reaction proceeds via ¹⁶O*(12.51, 13.97, 14.39, 14.92, 15.82, 16.23, 17.16, 17.82, 18.04) [± 40 keV] (1969HO13). See also (1970ME1N, 1975OT01), (1972BR1J) and (1972AL27; theor.). For the decay of T = 3/2 states of ¹⁷F, see reaction 9 in ¹⁷F and (1973AD02).

43. (a) ¹⁴N(α, d)¹⁶O Q_m = -3.1108
(b) ¹⁴N(α, dα)¹²C Q_m = -10.2725

Deuteron angular distributions to states of ¹⁶O have been reported at many energies up to E_α = 48 MeV: see (1971AJ02) for the earlier references and (1975TU02: E_α = 21 MeV) and (1972LO08: E_α = 29.98 MeV; see Table 16.17 (in PDF or PS)). The results of (1972LO08) are consistent with J^π = 5⁺, 6⁺ and 4⁺ for ¹⁶O*(14.40, 14.82, 16.29) [2p-2h] and with 6⁺ for ¹⁶O*(16.30) [4p-4h].

An experiment to test time-reversal invariance by the principle of detailed balance in this reaction and in ¹⁶O(d, α)¹⁴N leads to an upper limit of 0.2% for the time-reversal non-invarinat part of the reaction amplitudes (1971TH03).

The two-stage reaction (reaction (b)) at E_α = 22.9 MeV appears to proceed via ¹⁶O states at E_x = 9.85 ± 0.07, 10.37 ± 0.07 and 11.14 ± 0.07 MeV (1969BA17). See also (1971BA2Q, 1971BA2V, 1973OG1A, 1976LE1K) and (1971BU1K, 1971TE10; theor.).

44. ¹⁴N(⁶Li, α)¹⁶O Q_m = 19.2631

Angular distributions have been measured at E(⁶Li) = 5.3 to 6.0 MeV (1968RI13; α₀, α₁₊₂, α₃₊₄) and E(¹⁴N) = 27.6 MeV (1964WA1B; α₀).

45. ¹⁴N(¹¹B, ⁹Be)¹⁶O Q_m = 4.920

At E(¹⁴N) = 50 MeV angular distributions have been measured to ¹⁶O*(0, 6.1 (u), 7.0 (u), 8.9, 9.9, 10.3, 11.0 (u)) [u = unresolved] (1975KL1A). See also (1975PO10: E(¹¹B) = 113 MeV) and (1971AJ02).

46. ¹⁵N(p, γ)¹⁶O Q_m = 12.1277

The yield of ground state radiation (γ₀) has been measured for E_p = 0.15 to 27.4 MeV: see Table 16.18 (in PDF or PS) for a listing of the measurements and Table 16.19 (in PDF or PS) for a display of the parameters of the obeserved resonances.

Below E_p = 0.4 MeV capture to the ground state is dominant: S(0) = 64 ± 6 keV · b, a value which makes the oxygen side cycle in CNO burning more important than previously thought. Study of the direct radiative capture process leads to a single particle spectriscopic factor C²S = 1.8 ± 0.4 for ¹⁶O_g.s. (1974RO37). The cross section shows a great deal of structure up to E_p = 17 MeV. Above that energy the γ₀ yield decreases monotonically to 27.4 MeV. In the same energy region the γ-yield to ¹⁶O states at 6 - 7 MeV and ≈ 12.9 MeV is large and it also decreases with increasing energy (1973OC1A; prelim. results.).

Measurements with polarized protons have been made over the giant dipole resonance at E_x = 22.2 MeV (1972HA52) and over a broad E2 giant resonance at E_x ≈ 24 MeV (1974HA01). See also (1976BUZH). The giant M2 resonance is probably centered at E_x = 20.4 MeV (1974CH37).

Branching ratios and Γ_γ values for the low energy resonances are listed in Table 16.15 (in PDF or PS) (1968GO07, 1968WI15, 1973BR19). See also (1971AJ02).

See also (1972CA1H, 1973JA1D), (1972HA1Y, 1973GL1B, 1973GL1C, 1973HA1X, 1973HA1Q, 1973SU1E, 1974HA1N, 1974HA1C, 1975CA1T, 1976GL1E), (1972BA2D, 1973BA05, 1973GO23, 1973HO36, 1974DA30, 1975MA2A, 1975RA01, 1975RA02, 1975SN1B, 1975SN1C, 1976LO01, 1976MA2G; theor.) and (1971BA1A, 1973CL1E, 1973TR1E; astrophys. considerations).

47. ¹⁵N(p, p)¹⁵N E_b = 12.1277

Elastic scattering studies are reported for E_p = 0.6 to 11.7 MeV: see Table 16.20 (in PDF or PS) in (1971AJ02) and Table 16.18 (in PDF or PS) here. Observed anomalies are displayed in Table 16.19 (in PDF or PS) (1971DR06). Inelastic scattering has been studied for E_p = 8.5 to 11.6 MeV: the p₁ yield is dominated by a structure at E_p = 10.6 MeV, Γ_cm ≈ 650 keV (1971DR06). A study of the elastic yield and the polarization (E_p = 8.4 to 10.5 MeV) shows that a narrow s-wave resonance does not exist at the deuteron threshold (E_x = 20.74 MeV) (1975FI1E). See also (1973HO36; theor.).

48. ¹⁵N(p, n)¹⁵O Q_m = -3.542 E_b = 12.1277

The absolute total cross section has been measured with excellent resolution and statistics for E_p = 3.8 to 12 MeV by (1968BA42): observed resonances are displayed in Table 16.20 (in PDF or PS) (1968BA42) also discusses in detail the relationship of his results and the data reported in other experiments, including a comparison with analog states in ¹⁶N [see Fig. 5]. Excitation functions have also been reported from threshold to 13.6 MeV: see Table 16.20 (in PDF or PS) in (1971AJ02). Polarization measurements for n₀ have been carried out at E_p = 7.9 to 12.3 MeV (1965WA02) and at 10.3 and 11.3 MeV (1976BY1A, 1976BY1B). See also (1974LO1B) and (1972DU24, 1973BA05, 1973HO36, 1973VO1J, 1974HO1L, 1974MA07, 1975RO31, 1976AR1F; theor.).

49. (a) ¹⁵N(p, t)¹³N Q_m = -12.905 E_b = 12.1277
(b) ¹⁵N(p, ³He)¹³C Q_m = -10.6659

The yields of the first three triton and ³He groups have been measured for E_p = 24.0 to 43.5 MeV (1974PI05, 1975MI01). Polarized protons with E_p = 43.8 MeV have been used to study the transitions to ¹³C*(0, 3.68, 7.55, 15.11) and ¹³N*(0, 3.51, 7.38, 15.07) (1974MA12). See also (1970HA23, 1972HA1X).

50. ¹⁵N(p, α)¹²C Q_m = 4.9661 E_b = 12.1277

Excitation functions for α₀ and α₁ particles [corresponding to ¹²C*(0, 4.43)] and of 4.43 MeV γ-rays have been measured for E_p = 0.093 to 45 MeV: see Table 16.20 (in PDF or PS) in (1971AJ02) and Table 16.18 (in PDF or PS) here. Observed resonances are shown in Table 16.19 (in PDF or PS). Angular correlation measurements lead to J^π = 2^-, 1^-, 3^- and 1⁺ for ¹⁶O*(12.97, 13.09, 13.26, 13.66) (1969CL07). For E_p > 3.5 MeV there is continuing structure in the yield curves which is interpreted in terms of fluctuations: see (1971AJ02). For polarization measurements see (1976PE03, 1976PE1H: 0.34 to 1.21 MeV).

A study of α₁γ for E_p = 0.15 to 2.50 MeV leads to S(0) ≈ 0.1 keV · b and shows that this reaction makes a negligible contribution to hydrogen burning at stellar energies compared to the (p, γ₀) and (p, α₀) processes (1974RO37). See also (1973JA1D), (1974CL1F, 1975LA1J, 1976LA1J; applications), (1971BA1A; astrophys. considerations) and (1972MA1K, 1976GA1K; theor.).

51. ¹⁵N(d, n)¹⁶O Q_m = 9.9031

Observed neutron groups are displayed in Table 16.22 (in PDF or PS). Angular distributions have been reported for E_d to 6 MeV: see (1971AJ02) and (1971MU09, 1972FO17: E_d = 4.83 and 5.84 MeV) and (1973BA2C: E_d = 5.0, 5.5 and 6.0 MeV): l-values and spectroscopic factors are also shown in Table 16.22 (in PDF or PS).

Slow neutron thresholds have been observed to ¹⁶O*(10.954 ± 0.010, 11.080 ± 0.015) (1957WE1A). ¹⁶O*(10.95) γ-decays only to ¹⁶O*(7.12), J^π = 1^-. This suggests J^π = 0^- for ¹⁶O*(10.95), an assignment also strongly favored by the γ-γ correlation (1957BE61). See also ¹⁷O.

52. ¹⁵N(³He, d)¹⁶O Q_m = 6.6340

Angular distributions have been measured at E(³He) = 11 MeV (1969BO13, 1971BO02) and at E(³He) = 16.0 and 24.9 MeV (1969FU08): l- and S-values are shown in Table 16.22 (in PDF or PS). See also (1973FR1E), (1973OG1A), (1970CO30, 1972EN03, 1975HS01; theor.).

53. ¹⁵N(α, t)¹⁶O Q_m = -7.6869

Not reported.

54. ¹⁵N(¹¹B, ¹⁰Be)¹⁶O Q_m = 0.898

See (1975SC2C) and (1971AJ02).

55. ¹⁶N(β^-)¹⁶O Q_m = 10.418

The ground state of ¹⁶N decays to seven states of ¹⁶O: reported branching ratios are listed in Table 16.23 (in PDF or PS). The ground state transition has the unique first-forbidden shape corresponding to ΔJ = 2, yes, fixing J^π of ¹⁶N as 2^-: see (1959AJ76). For the β-decay of ¹⁶N*(0.12) see reaction 1 in ¹⁶N (1975PA01).

The α-decay of ¹⁶O*(8.87, 9.63, 9.85) has been observed: see (1971AJ02). The parity-forbidden α-decay from the 2^- state ¹⁶O*(8.87) has been reported: Γ_α = (1.03 ± 0.28) × 10^-10 eV [E_α = 1282 ± 5 keV] (1970HA42, 1974NE10). (1971WE14) suggests that the α-width of ¹⁶O*(7.12) is an order of magnitude smaller than that for ¹⁶O*(9.58). See also (1970SP1D).

Recently reported transition energies derived from γ-ray measurements are: E_x = 6130.43 ± 0.05 keV [E_γ = 6129.170 ± 0.043 keV (1975SH18)] and 7116.85 ± 0.14 keV [E_γ = 7115.15 ± 0.14 keV (1976AL16)]. See also (1967CH19, 1974AL11) and (1973DO1H, 1974WI1N, 1975BO1V, 1975DO10, 1976LO01; theor.).

56. (a) ¹⁶O(γ, n)¹⁵O Q_m = -15.669
(b) ¹⁶O(γ, 2n)¹⁴O Q_m = -28.8886

Recent papers reviewing this reaction are (1973DI1C, 1975BE60).

The absorption cross section and the (γ, n) cross section are marked by a number of resonances. Some of the reported structure is displayed in Table 16.25 (in PDF or PS) of (1971AJ02). In view of the availability of experiments using monoenergetic photons and good resolution and statistics we suggest, on the basis of the work of (1974VE06, 1975BE60, 1975BE1F, 1965CA14) that excited states of ¹⁶O are observed at E_x = 17.3 [u], 19.3 [u] and 21.0 MeV [u = unresolved], followed by the giant resonance whose principal structures are at ≈ 22.2 and 24.1 MeV, with additional structures at 23 and 25 MeV. See also (1972WA13; theor.). The best resolution achieved so far appears to be that of (1974VE06) who measured the (γ, n+γ, pn), (γ, pn) and (γ, 2n) cross sections separately to E_γ = 37 MeV. Besides the monoenergetic photon work, there are still a number of reports of bremsstrahlung studies: the most convincing of these is by (1975JO04) and (1970JU02). These time-of-flight data confirm the structure indicated above. See also (1970IS08, 1971BA2W, 1972TH12, 1973SY1A). The yield of reaction (a) has been measured for E_bs = 100 to 800 MeV (1971AD05, 1971FR11; also 6.18 γ). The absorption cross section has been measured from E_bs = 10 MeV to above the meson threshold (1975AH06). The cross section for reaction (b) has been measured between threshold and E_γ = 120 MeV: it is usually small compared to the (γ, n) cross section at corresponding energies (1970FI15). Polarization measurements for the n₀ group have been carried out at E_bs = 20 to 30 MeV and at 64 MeV (1970CO1G, 1971CO1E, 1973NA1F).

Branching ratios for the decay of ¹⁶O in the giant resonance region to various excited states in ¹⁵O are discussed in ¹⁵O (1976AJ04).

57. ¹⁶O(γ, p)¹⁵N Q_m = -12.1277

The (γ, p₀) cross section derived from the inverse capture reaction (reaction 46) confirms the giant resonance structure indicated above as do also the direct (γ, p₀) measurements. The total (γ, p) cross section is given by (1968DE07). For yields at higher energies see (1973MA1U: E_bs = 50 → 80 MeV) and (1971AD05: 100 → 800 MeV; 6.32 γ-ray). Branching ratios for the decays of ¹⁶O states in the giant resonance region to various excited states in ¹⁵N are discussed in ¹⁵N in (1976AJ04) and in (1973DI1C, 1975BE1F). For a comparison with results from the ¹⁵N(p, γ)¹⁶O reaction see (1974HA01).

58. (a) ¹⁶O(γ, d)¹⁴N Q_m = -20.7368
(b) ¹⁶O(γ, pn)¹⁴N Q_m = -22.9614
(c) ¹⁶O(γ, pp)¹⁴C Q_m = -22.3350
(d) ¹⁶O(γ, pd)¹³C Q_m = -28.2874

For reactions (b), (c) and (d) see (1973HA2B). For reaction (b) see reaction 56, (1972BU1J) and (1970WE1G, 1973KO1H, 1976HE12; theor.). For the previous work on all these reactions see (1971AJ02).

59. (a) ¹⁶O(γ, t)¹³N Q_m = -25.033
(b) ¹⁶O(γ, α)¹²C Q_m = -7.1616
(c) ¹⁶O(γ, 4α) Q_m = -14.4364

For reactions (a) and (c) see (1971AJ02). A study of the ¹⁶O(γ, α₀) reaction at θ = 45° and 90° shows a 2⁺ resonance at E_x = 18.2 MeV with an E2 strength which is spread out over a wide energy interval. A strong resonance corresponding to an isospin forbidden 1^- state at E_x ≈ 21.1 is also observed (1975SK06). See also (1973HA1Q, 1976MA62, 1976MA1D) and (1971AJ02).

60. ¹⁶O(γ, γ)¹⁶O

The differential scattering cross section has been measured for E_γ = 18.5 to 33 MeV: the main giant resonance peaks are located at ≈ 22 and ≈ 25 MeV (1967LO1B). (1970AH02) report resonances at E_γ = 22.5 ± 0.3, 25.2 ± 0.3, 31.8 ± 0.6 and 50 ± 3 MeV: the dipole sum up to 80 MeV exceeds the classical value 60 NZ/A MeV · mb by a factor 1.4. For lifetime measurements of ¹⁶O*(6.9, 7.1), see Table 16.19 (in PDF or PS) in (1971AJ02); for widths, see Table 16.12 (in PDF or PS) in (1971AJ02). The separation between the (7.12) and (6.92) γ-lines is 199.8 ± 0.5 keV (1970SW03). Based on 7116.85 ± 0.14 keV (Table 16.9 (in PDF or PS)), E_x for the lower state is 6917.1 ± 0.6 keV.

61. (a) ¹⁶O(e, e)¹⁶O
(b) ¹⁶O(e, ep)¹⁵N Q_m = -12.1277

The ¹⁶O charge radius = 2.718 ± 0.021 fm (1973FE13, 1975SC18). See also (1971BE25) and (1971AJ02). Form factors for transitions to the ground and to excited states of ¹⁶O have been reported in many studies: see (1971AJ02) and (1970SI08, 1973BE49, 1973BE50). Table 16.24 (in PDF or PS) lists the excited states observed from spectra of inelastically scattered electrons. The isospin-forbidden (E1) excitation of ¹⁶O*(7.12) has been reported by (1975MI08, 1975MI13): the isovector contribution interferes destructively with the isoscalar part and has strength ≈ 1% of the T = 0 amplitude (1975MI08; and H.H. Miska, private communication).

The 0⁺ states ¹⁶O*(6.05, 12.05, 14.00) saturate ≈ 19% of an isoscalar monopole sum rule (1973BE50). As for the E2 strength it is distributed over a wide energy region: see Table 16.24 (in PDF or PS) and (1974HO20).

62. (a) ¹⁶O(τ⁺, τ⁺)¹⁶O
(b) ¹⁶O(τ^-, τ^-)¹⁶O

The small angle scattering of π⁺ and π^- has been studied at E_π = 155, 185 and 213 MeV (1975MU06). At E_π^- = 230 MeV, the excitation of ¹⁶O*(6.13) is reported (1974LI15). See also the "GENERAL" section here.

63. ¹⁶O(n, n)¹⁶O

Angular distributions have been measured at energies to E_n = 14.1 MeV: see Table 16.27 (in PDF or PS) in (1971AJ02) and Table 16.25 (in PDF or PS) here. Gamma rays have been observed corresponding to the ground state decay of ¹⁶O states at E_x = 6129.1 ± 1.2 keV [E_γ = 6127.8 ± 1.2 keV] (1966BE1A), 6906 ± 15, 7112 ± 10 and 8865 ± 3 keV (1971NY03). See also (1974HO1E, 1975PO08, 1976NO1F) and (1972JE01, 1973DA1H, 1973SC1L; theor.).

64. (a) ¹⁶O(p, p)¹⁶O
(b) ¹⁶O(p, 2p)¹⁵N Q_m = -12.1277
(c) ¹⁶O(p, pd)¹⁴N Q_m = -20.7368
(d) ¹⁶O(p, pα)¹²C Q_m = -7.1616

Angular distributions of elastically and inelastically scattered protons have been measured at many energies up to E_p = 1000 MeV: see Table 16.27 (in PDF or PS) in (1971AJ02) and Table 16.25 (in PDF or PS) here. Parameters of the observed groups are displayed in Table 16.26 (in PDF or PS). Evidence, based on a study of the angular distribution and polarization involving ¹⁶O*(8.87) [J^π = 2^-], has been obtained by (1976LE16) for an octupole (E3) giant resonance of predominantly isoscalar nature centered near E_x ≈ 35 MeV, Γ ≈ 5 MeV.

For reaction (b) see (1971EI06, 1971HA61) and ¹⁵N in (1976AJ04). For reaction (c) see (1971AJ02) and (1976GO1E). At E_p = 46.8 MeV reaction (d) proceeds predominantly via ¹⁶O*(11.0) (1971EP03). See also (1972BO71) and (1971AJ02), (1969BU1B, 1970QU1C, 1971BA1K, 1971LO25, 1973GO27, 1974AL1G, 1975HI02, 1976NO02), (1971GA1J, 1972PA1A, 1973TH1A, 1975IG1A, 1975KA2D), (1970BA1F, 1970CZ1A, 1971FE10, 1971HE25, 1971RA36, 1972AU1A, 1972BO08, 1972BO39, 1972GE07, 1972GE16, 1972JA1C, 1972JO1A, 1972KE10, 1972LE27, 1972LE28, 1972LE1G, 1972PE04, 1972ST29, 1972WI16, 1973BL02, 1973GE01, 1973GE07, 1973GU1A, 1973JA13, 1973MI19, 1973RU07, 1973SC1L, 1973VA18, 1974BE22, 1974CI02, 1974GO1G, 1974GU21, 1974MA40, 1974PE1D, 1974SC1K, 1974SC1E, 1974SI13, 1974ZE04, 1975AN1N, 1975BA1H, 1975CL1D, 1975DU1A, 1975FR06, 1975GE05, 1975MA18, 1975MA50, 1975SC1T, 1975SM01, 1975TH03, 1976DAZH, 1976GO1E, 1976JA03, 1976YA08; theor.) and ¹⁷F.

65. (a) ¹⁶O(d, d)¹⁶O
(b) ¹⁶O(d, pn)¹⁶O Q_m = -2.2246

Angular distribution studies have been carried out for E_d up to 81.6 MeV: see Table 16.27 (in PDF or PS) in (1971AJ02) and Table 16.25 (in PDF or PS) here. Observed deuteron groups are displayed in Table 16.26 (in PDF or PS) (1974DU06). For reaction (b) see (1971NE07). See also (1972PA1A), (1969VE09, 1970EL16, 1970OH1C, 1971DO1A, 1971SI24, 1972DM01, 1972GA16, 1974CH58, 1975BO1P, 1975CO12, 1976CO01, 1976LE1U: theor.) and ¹⁸F in (1978AJ03).

66. ¹⁶O(t, t)¹⁶O

Angular distibutions are reported for E_t to 20.01 MeV: see Table 16.27 (in PDF or PS) in (1971AJ02) and Table 16.25 (in PDF or PS) here. See also (1976LE19; theor.) and ¹⁹F in (1978AJ03).

67. ¹⁶O(³He, ³He)¹⁶O

Angular distributions have been measured to E(³He) = 71 MeV: see Table 16.27 (in PDF or PS) in (1971AJ02) and Table 16.25 (in PDF or PS) here. Inelastic groups are shown in Table 16.26 (in PDF or PS) (1974MO26). See also (1970KA1D, 1975GO1L), (1974HA1C) and (1974CH58, 1974KU15, 1975SI09, 1976LE19; theor.).

68. (a) ¹⁶O(α, α)¹⁶O
(b) ¹⁶O(α, 2α)¹²C Q_m = -7.1616

Angular distributions of α-particles have been measured up to E_α = 146 MeV: see Table 16.27 (in PDF or PS) in (1971AJ02) and Table 16.25 (in PDF or PS) here. The fraction of the isoscalar quadrupole (T = 0, E2) energy weighted sum rule (EWSR) exhausted between E_x = 17 and 25 MeV is 40⁺²⁰_-10% (1976HA27). See also (1975KN05, 1975MO04, 1976BU15, 1976YO02). The forward angular behavior of the giant resonance structure for E_x = 23 - 24 MeV is consistent with l = 0 transfer while l ≥ 3 contributions cannot be excluded above E_x = 20 MeV. For low-lying states coupled channel calculations are required to describe the angular distributions to the 2⁺ and 4⁺ states at 9.85 and 10.35 MeV while the 1^-, T = 0 states require a microscopic wave function analysis (1976HA27).

Reaction (b) proceeds via excited states of ¹⁶O: see (1971GU15, 1975SH1K). (1976CH12) find N_eff = 0.34^+0.09_-0.05 at E_α = 850 MeV [square well]. (1975SH1K) report that the principal parent of ¹⁶O in and α-cluster model is ¹²C_g.s., and not ¹⁴C*(4.4).

69. (a) ¹⁶O(⁶Li, ⁶Li)¹⁶O
(b) ¹⁶O(⁷Li, ⁷Li)¹⁶O
(c) ¹⁶O(⁷Li, tα)¹⁶O Q_m = -2.4668

For studies of the elastic scattering see Table 16.25 (in PDF or PS). See also (1974MI1F), (1973FO1A, 1975GR41, 1976FI1F) and (1970SC31, 1972WA31, 1976OH03; theor.). For a study of d-α angular correlations see ²⁰Ne in (1978AJ03) and (1975AR20). For reaction (c) see (1974PA16) and ²⁰Ne in (1978AJ03).

70. ¹⁶O(⁹Be, ⁹Be)¹⁶O

The elastic scattering has been studied for E(¹⁶O) = 25.7 to 29.5 MeV (1975FU05). See also (1974TA1C).

71. (a) ¹⁶O(¹⁰B, ¹⁰B)¹⁶O
(b) ¹⁶O(¹¹B, ¹¹B)¹⁶O

The elastic scattering angular distributions have been studied at E(¹⁰B) = 100 MeV (1975NA15) and, in reaction (b), at E(¹⁶O) = 27, 30, 32.5, 35 and 60 MeV (1972SC03). At E(¹⁶O) = 60 MeV, angular distributions involving states of ¹¹B and ¹⁶O*(0, 6.1, 7.0, 10.34) have been measured by (1972SC17). See also (1974DE17, 1974KO1P; theor.).

72. ¹⁶O(¹²C, ¹²C)¹⁶O

The elastic scattering has been studied at E(¹⁶O) up to 168 MeV: see reaction 64 in (1971AJ02) and Table 16.25 (in PDF or PS) here. The scattering to ¹⁶O*(6.05, 6.13, 6.92, 7.12, 8.9, 10.3) has also been studied [see Table 16.25 (in PDF or PS)] (1973GU12, 1976SP01) and the populations of ¹⁶O*(11.1) (1975SH24) and ¹⁶O*(15) (1973GU12) have been reported. See also (1970RO23). Most of the studies of this reaction have involved yield measurements as they apply to compound structures in ²⁸Si: see (1978EN06) and (1972MA29, 1972ST09, 1973MA1N, 1974MA1L, 1975MA2C, 1975SH24, 1976CH13, 1976CH1Y, 1976EY01, 1976SP03). For spallation experiments see (1974WI05).

73. (a) ¹⁶O(¹³C, ¹³C)¹⁶O
(b) ¹⁶O(¹⁴C, ¹⁴C)¹⁶O

The elastic scattering has been studied at E(¹³C) = 36 MeV (1976WE21). See also (1974BE1J, 1975RA33; theor.). The elastic scattering in (b) has been studied at E(¹⁶O) = 20, 25 and 30 MeV (1975SC35).

74. (a) ¹⁶O(¹⁴N, ¹⁴N)¹⁶O
(b) ¹⁶O(¹⁵N, ¹⁵N)¹⁶O

The elastic scattering angular distributions have been studied at E(¹⁴N) and E(¹⁵N) = 25 MeV (1971BO1U), at E(¹⁴N) = 79 MeV (1976MO03) and at E(¹⁴N) = 155 MeV (1975NA15). For yield measurements see (1973GO01, 1974ST1N, 1976ST12) and ³⁰P and ³¹P in (1978EN06). See also (1975VO1B) and (1973KA46, 1974BA40, 1975MO23; theor.).

75. ¹⁶O(¹⁶O, ¹⁶O)¹⁶O

The angular distributions of elastically scattered ¹⁶O ions have been measured with E(¹⁶O) up to 140.4 MeV: see reaction 66 in (1971AJ02) and Table 16.25 (in PDF or PS) here. See (1973GO01) for a general study of the elastic scattering. The angular distributions corresponding to the excitation of the first four excited states of ¹⁶O have been studied at E(¹⁶O) = 51.5 MeV (1974RO04) and at 140.4 MeV (1962WI09). The astrophysical import of the cross section for elastic scattering (and of the total reaction cross section) has been studied by (1974SP06). For other yield measurements see ³²S in (1978EN06) and (1974HA44, 1974RO04, 1974VA18). See also (1973RE13).

76. (a) ¹⁶O(¹⁷O, ¹⁷O)¹⁶O
(b) ¹⁶O(¹⁸O, ¹⁸O)¹⁶O

Angular distributions of elastically scattered ions have been studied at E(¹⁶O) = 24, 28 and 32 MeV (1973GE04) and E(¹⁷O) = 53.0, 57.1, 61.5 and 66 MeV (1975KA24) [reaction (a)] and at E(¹⁶O) = 24, 28 and 32 MeV (1972GE18), 31.5 and 42.0 MeV (1975RE15), 39.9, 44.8, 49.9 and 54.8 MeV (1972SI16) and 41.8 and 51.9 MeV (1974VA22: also ¹⁶O*(6.1)), and at E(¹⁸O) = 53.1, 57.4, 61.6, 76.5 and 89.3 MeV (1975KA24). See also ¹⁷O, and ¹⁸O in (1978AJ03).

See also (1973FI1C, 1974GO1L, 1975VO1B) and (1973BA2F, 1974BA46, 1974BE1J, 1974BO13, 1974YU01, 1975IM04, 1975WO1E; theor.) [reaction (a)] and (1973FI1C, 1973VO1E, 1975VO1B ) and (1973BO1H, 1973MC1D, 1974GE02, 1974KU1E, 1975GR41, 1976GL08, 1976IM01, 1976OH03; theor.) [reaction (b)].

77. ¹⁶O(¹⁹F, ¹⁹F)¹⁶O

Angular distributions of elastically scattered ions have been studied at E(¹⁶O) = 21.4 and 25.8 MeV (1975MO31) and at E(¹⁹F) = 33 and 36 MeV (1973GA14). See also ¹⁹F in (1978AJ03), (1973VO1E, 1975VO1B) and (1976OH03; theor.).

78. ¹⁶O(²⁰Ne, ²⁰Ne)¹⁶O

Elastic scattering angular distributions have been measured at E(¹⁶O) = 40.7, 51.1 and 59.4 MeV (1975ZI1C).

79. ¹⁷O(p, d)¹⁶O Q_m = -1.918

Angular distributions for the ground state deuteron group have been studied at E_p = 8.62, 9.56, 10.5, 11.16 and 11.44 MeV (1975CR05). At E_p = 31 MeV, angular distributions are reported for the deuterons corresponding to ¹⁶O*(0, 6.05 + 6.13, 7.12, 8.87, 10.35, 12.97, 13.26). States at E_x = 15.22 and 15.42 MeV were also observed. Spectroscopic factors were obtained from a DWBA analysis (1970ME01).

80. ¹⁷O(d, t)¹⁶O Q_m = 2.115

At E_d = 52 MeV the spectrum at 10° is dominated by ¹⁶O*(0, 6.13, 8.87, 12.97, 13.26, 18.97, 19.79). ¹⁶O*(18.97, 19.79) are assigned J^π = (4)^-; T = 1 and (4); 0, respectively. Spectroscopic factors are given for various of the ¹⁶O states (1974MA23). See also reaction 29 in ¹⁶N, (1973WA1E) and (1975HS01, 1976SC36; theor.).

81. ¹⁷O(³He, α)¹⁶O Q_m = 16.436

Angular distributions to many states of ¹⁶O have been observed at E(³He) = 11 MeV: see Table 16.22 (in PDF or PS) for l- and S-values (1971BO02). At E(³He) = 36 MeV the widths of ¹⁶O*(18.97, 19.79) are < 16 and < 37 keV, respectively (1974DOZO). See also (1976WAZS) and (1971AJ02).

82. (a) ¹⁸O(p, t)¹⁶O Q_m = -3.7070
(b) ¹⁸O(p, pt)¹⁵N Q_m = -15.8347
(c) ¹⁸O(p, tα)¹²C Q_m = -6.2274

Angular distributions of tritons (reaction (a)) have been measured for E_p to 43.7 MeV: see (1971AJ02) for the earlier work and (1974FL09: E_p = 20 MeV; t₀ → t₅, t₇), (1974PI05: E_p = 20.0, 24.4, 29.8, 37.5, 43.6 MeV; t₁₊₂, t₃₊₄, t₅, t₈), (1973PI09: E_p = 24.4 MeV (polarized protons); t₀, t₁₊₂, t₃ → t₅, t₇, t₈) and (1972AD10: E_p = 41.7 MeV; t₀, t₁₊₂ and t to ¹⁶O*(11.26, 12.05, 16.33, 22.72)). See also (1970OL1B). Most of the states are more strongly populated than expected on the basis of simple calculations: it is suggested that complete coupled channels calculations may be necessary [see (1972AD10, 1974FL09)]. The population of ¹⁶O*(22.7, 24.5) is consistent with L = 0 and 2, respectively, and with assignments of T = 2, J^π = 0⁺ and 2⁺ (1964CE05). A study, at E_p = 43 MeV, of decay of the first T = 2 state at E_x = 22.72 MeV shows that it decays via proton emission [reaction (b)] with branchings of (25 ± 6)%, (22 ± 5)% and (15 ± 5)% to ¹⁵N*(0, 5.27 + 5.30, 6.32). The α-decay [reaction (c)] is not observed: the branchings to ¹²C*(0, 4.4) are (1.1 ± 4.0)% and (0.0 ± 3.4)%. The remaining decay modes have not been determined (1973KO02). See also (1973SO07, 1974MC1F, 1975CH18, 1975HO06, 1975IB01, 1975SE09; theor.) and ¹⁹F in (1978AJ03).

83. ¹⁸O(α, ⁶He)¹⁶O Q_m = -11.218

Angular distributions have been measured at E_α = 58 MeV to ¹⁶O*(0, 6.1, 6.92, 7.12). Groups at E_x = 10.4, 13.3 ± 0.1 and 16.3 ± 0.1 MeV were also observed. The cross sections are about a factor of 20 smaller than in the ¹⁸O(p, t) reaction but the angular distributions are consistent with a direct transfer mechanism (1975VA01). See also (1975VA1F).

84. ¹⁸O(¹⁸O, ²⁰O)¹⁶O Q_m = -0.628

See (1972EY01, 1976KUZX) and ²⁰O in (1978AJ03).

85. (a) ¹⁹F(p, α)¹⁶O Q_m = 8.1148
(b) ¹⁹F(p, 2d)¹⁶O Q_m = -15.733

Angular distributions have been reported at many energies to E_p = 44.5 MeV: see Table 16.30 (in PDF or PS) in (1971AJ02) and (1964BR12: E_p = 2.06 to 3.30 MeV; α₀) and (1975BU1B: E_p = 13.5 to 18.0 MeV; α₀). Observed states of ¹⁶O are displayed in Table 16.31 (in PDF or PS) in (1971AJ02).

Very accurate γ-ray measurements are reported by (1967CH19) [see reaction 55] and (1970GA09) [the E_γ of the 8.87 → 6.13 transition is 2741.5 ± 0.5 keV]. The E0 transition (6.05 → 0; 0⁺ → 0⁺) has been investigated in some detail: the internal conversion to pair production ratio (4.00 ± 0.46) × 10^-5 (1963LE06). The ratio of double γ-emission to pair production Γ_E1E1/Γ_E0(τ) ≤ 1.1 × 10^-4 (1964AL18), (2.5 ± 1.1) × 10^-4 (1975WA20). The τ_m for ¹⁶O*(6.05) = 96 ± 7 psec (1973BI17). An attempt to observe a scalar boson produced in the decay of ¹⁶O*(6.05) was unsuccessful; together with other results it demonstrates that the mass of such a boson cannot be 1.030 ≤ m ≤ 18.2 MeV (1974KO1Q).

¹⁶O*(6.13) has also been studied extensively: |g| = 0.55 ± 0.04, τ_m = 26.6 ± 0.7 psec (1973BR31). A search for double positron-electron pair creation by the 6.13 MeV γ-ray was unsuccessful: the ratio of the cross section for production of such a double pair to the cross section for formation of a single pair is -(2 ± 5) × 10^-5 (1972WI09). See also (1971BE60, 1972VA1H, 1976KA1N). For γ-ray branching ratios and Γ_γ for these and other transitions see Table 16.15 (in PDF or PS). See also (1971AJ02) and ²⁰Ne in (1978AJ03).

See also (1973LI1F, 1974KRZE), (1971ST06, 1973GO1M, 1973GO1N, 1974LO1B) and (1974LE1H, 1975BU1H, 1975GO1T, 1975SW1B; applications). For reaction (b) see (1971DE1F).

86. ¹⁹F(³He, ⁶Li)¹⁶O Q_m = 4.095

Angular distributions have been measured at E(³He) = 22.4, 30 and 40.7 MeV (1972OH01; g.s.), 28 MeV (1970KL09; g.s. of ¹⁶O and various ⁶Li states) and 40.7 MeV (1971DE14; to ¹⁶O*(6.13, 6.92, 7.12, 8.87, 11.0, 12.5, 13)). See also (1972YO02).

87. ¹⁹F(α, ⁷Li)¹⁶O Q_m = -9.233

The ground state angular distribution has been measured at E_α = 42 MeV (1968MI05).

88. (a) ²⁰Ne(γ, α)¹⁶O Q_m = -4.7313
(b) ²⁰Ne(p, pα)¹⁶O Q_m = -4.7313

For reaction (a) see (1975SK06) and ²⁰Ne in (1978AJ03). See also (1973CL1E; astrophys.). For reaction (b) see (1967CH04).

89. ²⁰Ne(d, ⁶Li)¹⁶O Q_m = -3.2576

Angular distributions have been studied at E_d = 40 MeV (1973KI1C, 1974EP1B; to ¹⁶O*(0, 8.87)). See also (1975BE01: quote data at 36 MeV). At E_d = 55 MeV, θ = 16°, the spectrum is dominated by ¹⁶O*(0, 6.1, 6.9, 9.85). ¹⁶O*(8.87, 10.35) are also observed (1971MC04). See also (1975CO1N).

90. ²⁰Ne(³He, ⁷Be)¹⁶O Q_m = -3.145

At E(³He) = 30 MeV angular distributions involving ¹⁶O*(0, 6.1) and the first two states of ⁷Be are reported by (1970DO1H). See also (1971DE37: E(³He) = 41 MeV), (1975AU01) and (1973KL1B; theor.).

91. ²⁰Ne(α, 2α)¹⁶O Q_m = -4.7313

At E_α = 78.6 MeV the reaction goes predominantly to ¹⁶O_g.s. with a small yield to ¹⁶O*(7.1). Quasifree α-α scattering plays an important role in the reaction (1974EP01).

92. ²⁸Si(α, ¹⁶O)¹⁶O Q_m = -9.5928

See (1967VA18).