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GENERAL: See also Table 17.2 [Table of Energy Levels] (in PDF or PS).

Theory: (1956BA1J, 1956KA1C, 1956KI1C, 1956LE1C, 1956SC1E, 1956VI1A, 1957AM1B, 1957AM1C, 1957FA1B, 1957FE1A, 1957PE1D, 1957RA1B, 1957TA1C, 1958BA32, 1958NI1D).

1. 13C(α, n)16O

Qm = 2.203

Eb = 6.348

Observed resonances for E_α = 1 to 5 MeV are listed in Table 17.3 [Resonances in ¹³C(α, n)¹⁶O and ¹⁶O(n, α)¹³C] (in PDF or PS) (1953JO1A, 1954TR09, 1956BE98, 1956BO61, 1956RU1A, 1957WA46), together with those observed in ¹⁶O(n, α)¹³C. The observed cross section of ¹³C(α, n)¹⁶O is closely matched by that calculated from the inverse reaction, for E_α = 4.0 to 5.2 MeV (1957WA46). Assignments for J^π in the range ¹⁶O*(7.1 to 9.0 MeV) are derived from angular distributions (1956SC1C, 1957WA46). The existence of additional broad states underlying this region is indicated by the analysis (1956RU1A, 1957WA46). Reduced widths have been tabulated for a number of levels by (1957WA46); it is of interest that θ²_n and θ²_α generally differ by less than one order of magnitude (1957WA46). The implications of the present reaction for element synthesis in stars are discussed by (1955FO1C, 1957BU66, 1957SA1B). See also (1954NA1B, 1956BA1K).

2. 14C(α, n)17O	Qm = -1.825
	Q0 = -1.820 ± 0.002 (1956SA06).

3. 14N(α, p)17O

Qm = -1.197

Proton groups have been observed to the ground and first excited states of ¹⁷O (1951RO1D, 1953HJ1A, 1953HJ1B).

4. 15N(d, n)16O

Qm = 9.886

Eb = 14.032

The excitation function has been measured from 0.5 to 5.3 MeV. Above E_d = 1.0 MeV pronounced peaks are observed, presumably to be ascribed to numerous overlapping resonances. Angular distributions are generally well accounted for by the exchange stripping theory of (1957OW03), with an admixture of heavy-particle stripping which is almost constant for E_d > 1 MeV (1958WE31).

5. 15N(d, p)16N

Qm = 0.267

Eb = 14.032

The excitation curve has been obtained for E_d = 0.3 to 2.7 MeV. There is some resonance structure at E_d = 1.3 and 1.9 MeV corresponding to ¹⁷O*(15.2 and 15.8 MeV) (1957BO04). See also ¹⁶N.

6. 15N(d, α)13C

Qm = 7.683

Eb = 14.032

See (1940HO1A).

7. 15N(t, n)17O

Qm = 7.774

Not reported.

8. 15N(3He, p)17O

Qm = 8.539

Not reported.

9. 15N(α, d)17O

Qm = -9.812

Not reported.

10. 16O(n, γ)17O	Qm = 4.146
	σcapt. < 0.2 mb (1955HU1B).

11. 16O(n, n)16O

Eb = 4.146

The cross section is almost constant at 3.76 b from thermal energies to E_n = 0.3 MeV (1958HU18). Observed resonances are indicated in Table 17.4 [Resonances in ¹⁶O(n, n)¹⁶O] (in PDF or PS) (1952BA1D, 1955OK01, 1956BE98, 1957WA46, 1958HU18, 1958LA09, 1958ST28). (1958FO67) have measured angular distributions at six energies in the range E_n = 0.7 to 2.2 MeV and have derived the phase shifts up to 2.4 MeV. From measurements in the range E_n = 0.1 to 1.7 MeV, (1958LA09) find that the E_n = 1.65 MeV resonance is due to a 7/2^- state. Phase shifts for E_n = 0.2 to 1.4 MeV derived by (1958ST28) from total cross section measurements are in good agreement with those of (1958FO67) except for a 5° discrepancy in δ_3/2⁺ at E_n = 0.73 MeV. According to (1958ST28), the s-wave shifts from 0.2 to 2.3 MeV fit hard-sphere scattering with R = 5.6 × 10^-13 cm. (1958FO67) find that the s- and d-wave phase shifts and the locations of ¹⁷O(g.s.; d_5/2), ¹⁷O*(0.87; s_1/2) and ¹⁷O*(5.08; d_3/2) can be adequately described by a potential well 40 - 45 MeV deep, with a diffuse boundary. See also (1956VI1A).

The angular distribution has also been measured at E_n = 5 MeV (1958HI68). Polarization studies have been carried out for E_n = 0.25 to 0.6 MeV by (1954WI42, 1955OK01) and for E_n = 0.7 to 1.4 MeV by (1958ST28). Cross sections at E_n = 14 MeV are tabulated by (1958HU18). See also (1956BA1K, 1956FL1B, 1957MC1B) and (1955AJ61).

12. 16O(n, n')16O*

Eb = 4.146

The yield of γ-rays shows marked structure in the range E_n = 7 - 10 MeV (1958HU18). At E_n = 14.1 MeV, the inelastic scattering cross section is 0.5 b (1953CO67).

13. 16O(n, 2n)15O

Qm = -15.655

Eb = 4.146

See (1955AJ61).

14. 16O(n, p)16N

Qm = -9.619

Eb = 4.146

The cross section rises from threshold to a peak of 89 ± 30 mb at E_n = 14 MeV, falling to ≈ 60 mb at 18 MeV (1954MA97). See also (1955AJ61) and (1953KI1A, 1956FA1C, 1958HU18).

15. 16O(n, d)15N

Qm = -9.884

Eb = 4.146

See (1953KI1A, 1955HU1B).

16. 16O(n, α)13C

Qm = -2.203

Eb = 4.146

The cross section has been measured from threshold to 4.2 MeV by (1955SE1A) and from 4.0 to 5.2 MeV by (1957WA46). All of the ¹⁶O levels observed in ¹³C(α, n)¹⁶O from ¹⁷O*(7.92 to 8.96 MeV) are also observed in this reaction, with good agreement in level position: see Table 17.3 [Resonances in ¹³C(α, n)¹⁶O and ¹⁶O(n, α)¹³C] (in PDF or PS). Observed cross sections correspond closely to those calculated from the inverse reaction (1957WA46). At higher energies, using continuous fast neutrons, (1956KI1B) report 18 levels in ¹⁷O in the range E_x = 6.8 to 9.7 MeV, and (1953GI1B) reports 32 levels in the range E_x = 6.8 to 12.8 MeV. See also (1953KI1A, 1955HU1B, 1955HU1C, 1956BA1K).

17. 16O(d, p)17O	Qm = 1.919
	Q0 = 1.918 ± 0.004 (1957BR82);
	Q0 = 1.915 ± 0.010 (1954SP01);
	Q0 = 1.885 (1955KH35).

¹⁷O levels derived from observed proton groups are listed in Table 17.5 [States of ¹⁷O from ¹⁶O(d, p)¹⁷O and ¹⁹F(d, α)¹⁷O] (in PDF or PS) (1951BU1A, 1957BR82: see also (1953KH1A, 1954SP01, 1955KH35)), together with those from the α-groups from ¹⁹F(d, α)¹⁷O. The J^π assignments are derived from stripping analysis: see (1955AJ61, 1956GR37, 1958RI1A). It is noted that the relatively large capture probabilities corresponding to ¹⁷O*(0, 0.87, 3.8, 5.08) are consistent with the assumption that these are relatively pure single particle states formed from an ¹⁶O core with 1d, 2s, 1f and 1d neutrons, respectively. The states at E_x = 3.06 and 4.55 MeV must be presumed to arise from more complicated configurations (1956GR37).

An earlier report that the 871 keV level might be a close doublet (1956DO41) is not confirmed by (1957BR82, 1957MA1C, 1957MO1B). Q for this level is 1049.0 ± 2.2 keV (1957MO1B), 1048 ± 2 keV (1956DO41), 1047 ± 4 keV (1957BR82). The γ-ray energy is 870.5 ± 2.0 keV (1952TH24), 869 ± 3 keV (1955MA36); the internal conversion coefficient is consistent with E2 (1952TH24). The lifetime is τ_m = (2.5 ± 1) × 10^-10 sec (1953TH14): this value indicates a considerable enhancement of the single particle transition rate. Possible models are discussed by (1956BA1J, 1956KA1D, 1956SC1E, 1957AM1B, 1957AM1C, 1957FA1B, 1957RA1B, 1958BA32).

Observed widths and shapes of ¹⁷O*(4.55 and 5.08 MeV) are in good accord with ¹⁶O(n, n)¹⁶O results (1957BR82). The ratio of ground state reduced widths is 1.30 (1956CA1D). See also (1955AJ61, 1955AL1D, 1955KH31, 1956EL1A), (1956IV1A; theor.) and ¹⁸F.

18. 16O(t, d)17O

Qm = -2.113

Not reported.

19. 16O(α, 3He)17O

Qm = -16.436

Not reported.

20. 17N(β-)17O* → 16O + n

Qm = 4.57

The half-life is 4.14 ± 0.04 sec (1948KN24), 4.15 ± 0.1 sec (1951ST1E), 4.16 ± 0.15 sec (1956FA1C). E_β(max) = 3.7 ± 0.2 MeV (1949AL04): log ft = 3.8. The β-decay proceeds to an excited state or states of ¹⁷O which in turn decay to ¹⁶O by neutron emission: the neutron spectrum has a maximum at 0.92 ± 0.07 MeV (1949AL04, 1949HA55) and a half-width < 0.5 MeV. See also (1957JO1D; theor.).

21. 17O(p, p')17O*

See (1954WA1A).

22. 17F(β+)17O

Qm = 2.767

See ¹⁷F.

23. 18O(p, d)17O

Qm = -5.842

See (1956TS1A).

24. 18O(d, t)17O

Qm = -1.810

Not reported.

25. 18O(3He, α)17O

Qm = 12.509

Not reported.

26. 19F(n, t)17O

Qm = -7.548

Not reported.

27. 19F(p, 3He)17O

Qm = -8.313

Not reported.

28. 19F(d, α)17O

Qm = 10.038

Observed alpha groups are displayed in Table 17.5 [States of ¹⁷O from ¹⁶O(d, p)¹⁷O and ¹⁹F(d, α)¹⁷O] (in PDF or PS) (1951BU1A, 1952WA1A). At E_d = 1.2 MeV, two γ-rays are observed with E_γ = 2.2 MeV (3.06 → 0.87) and 3.81 MeV. The absence of the direct ground state decay of the 3.06 MeV state is consistent with J = 1/2 (1956GO1Q, 1957MU1A).

29. 20Ne(n, α)17O

Qm = -0.608

See ²¹Ne.