(See Energy Level Diagrams for 15O)
GENERAL: See also (1976AJ04) and Table 15.18 [Table of Energy Levels] (in PDF or PS) here.
Shell model: (1976LI16, 1976SA37, 1977EM01, 1977PO16).
Special states: (1976LI16, 1977RI08).
Electromagnetic transitions: (1976LI16, 1976SH04, 1977HO04, 1978KR19).
Astrophysical questions: (1977BA1V, 1977SI1D, 1978BU1B, 1979PE1E, 1979WO07).
Special reactions involving 15O: (1976AB04, 1976BU16, 1976HE1H, 1976HI05, 1976LE1F, 1977AR06, 1977SC1G, 1978AB08, 1978BO1W, 1979AL22).
Pion capture and pion reactions: (1975KA1G, 1977BA24, 1977BA2G, 1978MO01, 1979LI11, 1979OS1F).
Applied work: (1976BE1X, 1977ST1M, 1977SU1G, 1977TH1H, 1978BI1M, 1978HI1D, 1978TI1A, 1978WI1F, 1978WO1C, 1979AL1Q, 1979DE1H, 1979WI1G).
Other topics: (1976SA1H, 1977BA3P, 1977EM01, 1978SH1B, 1979BE1H, 1979KA13).
Ground state properties of 15O: (1976FU06, 1976SA1H, 1977KO28, 1977PO16, 1977YO1D, 1978AR1R, 1978SL1B, 1979NO05).
The half-life of 15O is 122.24 ± 0.14 sec based on the values listed in Table 15.19 (in PDF or PS) of (1970AJ04) and on τ1/2 = 122.23 ± 0.23 sec (1977AZ01). log f0t = 3.637 [calculated from tables of (1971GO40)]. The K/β+ ratio is (10.7 ± 0.6) × 10-4 (1972LE33). See also (1977BA48, 1978RA2A), (1978TA1U, 1979DA1D; astrophys.) and (1977AZ02, 1977RI08, 1977YO1E, 1979BA08, 1979OS1E, 1979TO1B; theor.).
Angular distributions have been measured at E(14N) = 73.9 MeV (1977MO1A; to g.s.) and 100 MeV (1975NA15; to 15O*(0, 5.18 + 5.24, 6.79 + 6.86)).
Elastic angular distributions have been studied at E(14N) = 41, 77 and 113 MeV (1971LI11). See also (1978MA1F).
Excitation functions and polarization measurements for these reactions have been measured over a wide range of energies: see Tables 15.20 in ((in PDF or PS) 1970AJ04, (in PDF or PS) 1976AJ04) and the text below. Observed resonances are displayed in Table 15.20 (in PDF or PS). For angular distributions see the write-ups of the residual nuclei in (1979AJ01, 1980AJ01) and in 13N, 14N and 14O. The 90° yield of γ0, measured for E(3He) = 5.24 to 13.95 MeV shows five resonances attributed to E1 transitions from Jπ = 1/2+ or 3/2+, T = 1/2 states in the GDR characterized by a considerable 3p-4h admixture: see Table 15.20 (in PDF or PS) (1978DE33; see also for ωγ). The yield of n0 (reaction (b)) shows resonances for E(3He) < 10 MeV and little structure above, to 30.6 MeV: see (1976AJ04) and (1978FE03; n0, 11.5 to 23.5 MeV; also n1 and n2+3+4, 14.5 to 26 MeV). The yield of protons (reaction (c)) shows some clear resonances below E(3He) = 4.5 MeV and some uncorrelated structures [see Fig. 3 in (1973SO04)] at higher energies (to E(3He) = 12 MeV), with the possible exception of states at Eres = 7.8, 9.2 - 9.6 and (10.5) MeV (1973SO04). For E(3He) = 16 to 30.6 MeV no appreciable structure is observed in the p0, p1 and p2 yields (1970SI15).
For reaction (d) see (1976AJ04) and (1976KA23; E(pol. 3He) = 33.3 MeV; polarization measurements; d0, d2+3). For reaction (e) see (1976AJ04). The elastic scattering (reaction (f)) shows some resonant structure near 3, 5 and 6 MeV and some largely uncorrelated structures in the range E(3He) = 16.5 to 24 MeV. There is some suggestion, however, of two resonances at E(3He) = 17 and 20 MeV (1972MC01). Polarization measurements have been carried out for E(pol. 3He) = 20.5 to 32.6 MeV for the groups to 12C*(0, 4.4). The elastic 66.8° data show a resonance-like behavior at E(pol. 3He) = 29 MeV (1977KA25). See also (1976AJ04). The yield of α-particles displays resonance structure below 8 MeV, and broad fluctuations for E(3He) = 12 to 18.6 MeV: see (1976AJ04). Polarization measurements are reported for E(pol. 3He) = 33.3 MeV for the α0 and α1 groups (1976KA23). For reaction (h) see (1976AJ04). For reaction (i) see (1976PA07; cross section in range 7 to 20 MeV). For π0 production see (1976WA10). See also (1976KR1C, 1976TOZM) and (1974LO1B, 1976RO1L, 1976WA1B).
Angular distributions of the n0 group have been measured for Eα = 18.4 to 23.1 MeV: see (1976AJ04).
States observed in this reaction are displayed in Table 15.21 (in PDF or PS) (1975BI06: E(6Li) = 59.8 MeV). Comparisons of angular distributions of the triton groups in this reaction and of the 3He groups to analog states in 15N have been made: analog correspondence is established for (10.48 - 10.80), (12.84 - 13.15(u)) and (15.05 - 15.49(u)) [Ex in 15O, Ex in 15N; u = unresolved] (1975BI06). See also (1976AJ04) for the earlier work on this reaction, (1977MA2G) and (1977FO1E).
At E(10B) = 100 MeV 15O*(12.89, 15.36) are very strongly populated (1973NA09). See also reaction 20 in 15N and (1977FO1E, 1979NA1G).
At E(11B) = 114 MeV, θlab = 7° the spectrum is dominated by 15O*(12.84, 15.05). 15O*(7.28, 10.48) are also populated (1974AN36).
At E(12C) = 187 MeV, θlab = 8° the spectrum is dominated by 15O*(12.84, 15.05) [assumed Jπ = 1/2-, 13/2+, respectively]. 15O*(7.28) [Jπ = 7/2+] is populated but 15O*(0, 6.79) are not observed (1974AN36). The situation is similar at E(12C) = 114 MeV but at E(12C) = 72 MeV (θlab = 11°) 15O*(0, 5.2, 7.28) are populated with comparable intensities (1974AN36). See also (1977FO1E, 1977PH1D, 1978HO1C, 1978MA1F).
For reaction (a) see (1976AJ04); for (b) see (1979PR07); for (c) see (1979OR01).
Observed groups are displayed in Table 15.22 (in PDF or PS).
At E(11B) = 114 MeV the states which are strongly populated are 15O*(5.24, 7.28, 11.2, 11.7) (1974AN36).
Observed resonances in the yield of γ-rays are listed in Table 15.23 (in PDF or PS). Branching ratios are displayed in Table 15.19 (in PDF or PS).
The cross section increases from (8.5 ± 3.7) × 10-12 b at 100 keV to (140 ± 30) × 10-12 b at 135 keV (1957LA13). Extrapolation from the Ep = 0.28 MeV resonance gives S(0) = 2.75 ± 0.50 keV · b, with zero slope to Ep = 0.05 MeV (1963HE11). Measurements of Eγ lead to Ex = 5183 ± 1, 5240.9 ± 0.4, 6175 ± 2, 6794 ± 2, 6858 ± 2, 8284.1 ± 0.8, 8922 ± 2 and 8978 ± 2 keV (1972KR14, 1972NE05, 1977DR02). See also Table 15.24 (in PDF or PS) in (1976AJ04). (1977DR02) find, on the basis of the analysis of (p, p) excitation curves and γγ correlation data, that the two states at Ex = 8922 keV are separated by ΔE = 0.5 ± 0.5 keV: for their parameters see Table 15.23 (in PDF or PS). This is in disagreement with the earlier work of (1972KR14) which assumed a larger ΔE, and suggests that the branching ratios for the 5/2+ and 1/2- states at Ex = 8.92 MeV shown in Table 15.19 (in PDF or PS) should be remeasured (1977DR02).
The 90° γ0 yield curve has been measured for Ep = 2.2 to 19.0 MeV: resonances are observed over most of the range in the γ0 yield. The (γ1 + γ2) yield is relatively weak (1970KU09). For Ep = 18 to 28 MeV the excitation function for γ0 decreases smoothly with energy: there is no evidence for structures (1975HA39). See also (1976AJ04).
Lifetime measurements are reported by (1977KE15): τm = 8.2 ± 1.0, > 3000, < 2.5, 16.0 ± 2.5 and 750 ± 200 fsec for 15O*(5.18, 5.24, 6.18, 6.86, 7.28), respectively. For questions related to astrophysics see (1974FO1F, 1975ZI1A, 1976AJ04, 1976BR1H, 1977CO1W). See also (1976TRZZ), (1974LO1B) and (1977YO1F, 1979RO12, 1979TR1G; applications).
The excitation function has been measured for Ep = 6.3 to 12 MeV (1964KU06). Observed resonances are displayed in Table 15.23 (in PDF or PS). See also (1978WA1D), (1977YO1G; applications) and 14O.
The yields of elastic and inelastic protons, and of γ-rays, have been studied at many energies: see (1959AJ76, 1970AJ04, 1976AJ04). Observed resonances are displayed in Table 15.23 (in PDF or PS). At higher energies excitation functions have been measured for the p0, p1 and p2 groups for Ep = 17 to 26.5 MeV: there is no evidence for resonant behavior but the p1 yield shows a large increase between Ep = 20 and 23 MeV (1972LU10). Total cross sections for the p0 → p9 groups have been measured at Ep = 8.6, 10.6, 12.6 and 14.6 MeV by (1973HA54). See also (1980FO05) and 14N.
Polarization measurements have been reported for Ep = 3.0 to 155 MeV: see Table 15.25 (in PDF or PS) in (1970AJ04), and (1976AJ04). A recent measurement of VAP for the p0 and p1 groups is reported at Ep-bar = 21 MeV (1979AO02). The depolarization parameter, D, has been determined for p0 at Ep = 16.15 MeV (1976CL1B; prelim.). See also (1978GO05) and (1976TH06; theor.).
See 12N in (1980AJ01).
Excitation functions for the ground state groups have been measured at Ep = 7 to 11 MeV: some resonant structure is indicated (see Table 15.23 (in PDF or PS)) (1970ME30). Total cross sections for the transitions to 12C*(0, 4.4) have been measured in the range Ep = 20.5 to 44.6 MeV (1974PI05). See also 12C in (1980AJ01).
Excitation functions and total cross section measurements have been carried out for the α0 group for Ep = 3.8 to 45 MeV: see (1976AJ04). Fairly sharp structures persist until Ep = 15 MeV (1974JA11): see Table 15.23 (in PDF or PS) for the parameters of observed resonances and in particular footnote e. Reaction (b), whose cross section has been measured to Ep = 52 MeV, displays a broad peak at ≈ 20 MeV (1974JA11, 1976IN04). For spallation studies see (1977MO1C, 1979RA20, 1979VD02, 1979WE06). See also (1975ZI1A; astrophys.).
Angular distributions have been studied at many energies in the range Ed = 0.9 to 11.8 MeV: see Table 15.27 (in PDF or PS) in (1970AJ04), and (1976AJ04). Observed states are displayed in Table 15.19 (in PDF or PS). Lifetimes have been measured for 15O*(5.24, 6.79, 7.28): τm = 3.2 ± 0.5 psec (1967BI11), < 28 fsec, 700 ± 150 fsec (1968GI11), respctively: see also Table 15.26 (in PDF or PS) in (1970AJ04). See also (1974LO1B), (1976LO1B; applied) and 16O in (1982AJ01).
Angular distributions have been obtained at E(3He) = 11 and 14 MeV: see (1976AJ04) and Table 15.24 (in PDF or PS).
Angular distributions of the t0 group have been studied at Eα = 56 MeV: see (1976AJ04).
Angular distributions have been measured for the n0 group at Ep = 3.95 to 18.5 MeV [and for the n2 group at Ep = 5.5 MeV]: see (1970AJ04) for a listing of the older references, and (1978CH09: n0; Ep = 11.98, 12.98, 14.58, 15.13, 15.28 MeV). See also (1980BY1A) and 16O in (1982AJ01).
Angular distributions for the t0, t1+2, t3, t4+5, t6 and t7 groups have been studied for E(3He) = 16.5 to 44.6 MeV: see (1976AJ04). See also Table 15.27 (in PDF or PS) in (1976AJ04).
The spectrum of photoneutrons has been investigated at many energies. Measurements over the giant dipole resonance region show the predominant strength is to the Jπ = 1/2- and 3/2- states Ex = 0 and 6.18 MeV, consistent with the basic validity of the single-particle, single-hole theory of photoexcitation in 16O. However, the positive parity states at Ex = 5.18, 5.24, 6.86 MeV are also populated suggesting some more complicated excitations in 16O: see (1970HO21) and the earlier references in (1970AJ04). See also (1979PH07) and 16O in (1982AJ01). The angular distributions of the ground state neutrons have been measured from threshold to Eγ = 28 MeV [see (1976AJ04)] and at Eγ = 57.8 and 80 MeV (1979GO1V). Polarization measurements are reported for Eγ = 21.6 to 25.7 MeV (1979NA1R). See also (1977CO1Y, 1977MA2H, 1978EL05, 1978SC11; theor.).
Reaction (a) goes primarily to 15O*(0, 6.18). Angular distributions have been reported at many energies for Ep = 18.5 to 155.6 MeV: see Table 15.30 (in PDF or PS) in (1970AJ04) and (1975RO27: Ep = 65 MeV; d0, d3). See (1975RO27) for a review of spectroscopic factors. See also (1978WH1A, 1979BO1A, 1979CA1A, 1979WH1A), 17F in (1982AJ01), (1976SI1A, 1980WH1A) and (1978HE02; theor.). For reaction (b) see (1976AJ04).
Angular distributions have been reported at a number of energies in the range Ed = 20 to 52 MeV [see (1970AJ04, 1976AJ04)] and at Ed-bar = 29 MeV (1978CO13; t0, t3). For determinations of C2S for 15O*(0, 6.2), and for a comparison of the results in the mirror reaction, see reaction 74 in 15N (1978CO13). See also 18F in (1978AJ03, 1983AJ01) and (1975FA06; theor.).
The p1/2 and p3/2 hole states at Ex = 0 and 6.18 MeV are strongly populated. Information on these and other states are displayed in Table 15.25 (in PDF or PS). Angular distributions have been measured at E(3He) = 5.2 to 36.6 MeV [see (1976AJ04) and Table 15.32 (in PDF or PS) of (1970AJ04)], at E(pol. 3He) = 33.3 MeV (1980LU03; α0, α3) and at 217 MeV (1974GE09, 1978VA05; α0, α3 and groups to higher, unresolved states). Branching ratios and multipole mixing ratios are displayed in Table 15.19 (in PDF or PS). (1978BE73) report τm of 15O*(5.24) = 3.25 ± 0.30 psec, |g| = 0.260 ± 0.028.
15O*(7.28) has an excitation energy of 7274.2 ± 1.4 keV (1967HE1A) (which is 23.2 keV below the Eb of 14N + p) and Jπ = 7/2+; thus it plays no significant role in determining the rate of the 14N(p, γ)15O reaction in stars (1967HE1A). See also (1978CH1P) and 16O in (1982AJ01).
At E(6Li) = 36 MeV angular distributions have been measured for the transitions 15Og.s. + 7Lig.s.,0.48 (1973SC26).
Angular distributions involing 15Og.s. have been investigated at E(10B) = 100 MeV (1975NA15).
See reaction 77 in 15N.
At Ep = 39.8 MeV angular distributions of t0 and t3 groups have been compared to those of the 3He groups to the analog states in 15N (1971OL04). At Ep = 45 MeV a state, assumed to be the Jπ = 5/2+, T = 3/2 analog of 15C*(0.74), is observed at Ex = 12.255 ± 0.013 MeV, Γcm = 135 ± 15 keV. The state decays by proton emission to the T = 1, 0+ state 14N*(2.31) (1978BE26; population of some T = 1/2 states is also reported).
Angular distributions are reported at E(3He) = 40.7 MeV involving (15Og.s. + 7Li*g.s.,0.48), (15O*5.19+5.24 + 7Li*g.s.,0.48) and (15O*6.18 + 7Lig.s.) (1971DE37, 1971DE04): see also the analog reaction 19F(3He, 7Be)15N [reaction 84 in 15N].