
^{18}F (1983AJ01)(See Energy Level Diagrams for ^{18}F) GENERAL: See also (1978AJ03) and Table 18.11 [Table of Energy Levels] (in PDF or PS). Shell model: (1977AN1P, 1977GR16, 1977SO1C, 1978CO08, 1978DA1N, 1978MA2H, 1979BU12, 1979DA15, 1980GO01, 1980KU05, 1980MA18, 1981EL1D, 1981ER03, 1981GR06, 1982KI02). Cluster, collective and deformed models: (1977BU22, 1978BU03, 1978PI1E, 1978SA15, 1978TA1A, 1979BU12, 1979SA31, 1980RO19, 1981CH24). Electromagnetic transitions: (1976MC1G, 1977BU22, 1977HA1Z, 1977HE1L, 1978BU03, 1978DE1K, 1978SA15, 1979SA31, 1980KO1L, 1980KU05, 1981CH24). Special states: (1977AN1P, 1977GR16, 1977HE18, 1977SH18, 1978AN1P, 1978BU03, 1978EN1D, 1978ER1C, 1978KO1W, 1978KR1G, 1978MA2H, 1978PI1E, 1978SA15, 1978TA1A, 1979BA35, 1979BU12, 1979DA15, 1979SA31, 1979WI1Q, 1979ZA07, 1980BR21, 1980GO01, 1980HA41, 1980MA18, 1980RO19, 1980SH1K, 1981AD1E, 1981AR1D, 1981BI03, 1981EL1D, 1981ER03, 1981SO03, 1982KI02, 1982NA03). Astrophysical questions: (1977SI1D, 1978WO1E, 1981WE1F). Applied topics: (1977FI13, 1978FR1R, 1978WI1F, 1978WO1C, 1979BA52, 1979KA07, 1979WI1G, 1980LA1K, 1980YA08). Complex reactions involving ^{18}F: (1977AS03, 1977SC1G, 1977YA1B, 1978SH18, 1979BO22, 1979VI09, 1980EV1A, 1980WI1K, 1980WI1L, 1980YA08, 1981GR08). Pion induced capture and reactions: (1977ST27, 1978SP07, 1981NI03). Other topics: (1977AN1P, 1977GR16, 1977SH18, 1977SO1C, 1978AN1P, 1978CO08, 1978DE1K, 1978EN1D, 1978GO1U, 1978JO1C, 1978KR1G, 1978MA2H, 1978SH1B, 1979BA35, 1979BE2L, 1979CO09, 1979DE18, 1979GO1W, 1979HW01, 1979KU04, 1979WI1Q, 1980BR21, 1980DE1F, 1980GO01, 1980TA1L, 1981AR1D, 1981BI03, 1981CH24, 1981EL1D, 1981ER03, 1981SO03, 1982FI1C, 1982KI02, 1982NA03). Ground and 1.12 MeV states of ^{18}F: (1976MC1G, 1977HA1Z, 1978ZA1D, 1980MA18, 1981AR1D).
Q_{1.12} = 0.13 ± 0.03 b (1974MI21); see also (1978LEZA).
The positron decay is entirely to the ground state of ^{18}O [J^{π} = 0^{+}, T = 1]; the halflife 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 ^{18}O_{g.s.} is allowed indicates J^{π} = 1^{+} for ^{18}F_{g.s.}. The ratio ε_{K}/β^{+} = 0.030 ± 0.002; see (1978AJ03). See also (1976BE1E, 1981BE2N, 1982PI1B) and (1980AF1A; theor.).
Crosssection measurements have been carried out in the range E(^{6}Li) = 1.9 to 36 MeV: see (1978AJ03) and (1976PO02; 4 to 13 MeV; ^{6}Li elastic), (1978SO01; 9 to 14 MeV and 20 MeV; α_{0}, α_{1}, α_{2}), (1980FU06; 20 to 36 MeV; ^{6}Li to ^{12}C*(0, 4.43)) and (1978CU03; 20 to 34 MeV; d to ^{16}O*(0, 6.13, 6.92, 7.12, 8.87, 10.36, 11.09, 16.3)). The cross section for the isospinforbidden α_{1} group [to ^{14}N*(2.31), 0^{+}, T = 1] is 1 to 2% of the cross section to the allowed α_{0} and α_{2} groups for E(^{6}Li) = 3.2 to 6 MeV (1981SC13) while for 9 to 14 MeV it varies from 0.4 to 1.8% (1978SO01). At 20 MeV, the α_{1} yield is 0.02% of the allowed yield (1978SO01). Structures are reported at E(^{6}Li) = 11.0 and 13.0 MeV in the α_{0} yield, at 11.5 and (13.0) MeV in the α_{1} yield and at ≈ 11.7 and 12.8 MeV in the α_{2} yield (1978SO01), while (1981SC13) report a resonance in the α_{1} yield at E(^{6}Li) = 4.2 MeV: E_{x} = 15.99 ± 0.02 MeV, Γ_{c.m.} = 290 ± 30 keV, J^{π} = 2^{+} (onelevel BW fit). It is suggested that this resonance is due to 2^{+} states with T = 0 and T = 1 which are unresolved (1981SC13). The excitation functions for the ^{6}Li ions to ^{12}C*(0, 4.43) shows a single isolated structure at E(^{6}Li) = 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 ^{18}F (1980FU06). At E(pol. ^{6}Li) = 20 MeV analyzing power measurements are reported for many deuteron and α groups and for elastically scattered ^{6}Li ions (1978MA13, 1979MA1T). Breakup processes have been studied by (1980NE05), cross sections at very high energies by (1980SK1A), fusion by (1981DE1H, 1981DE2K). See also ^{16}O, ^{17}O in (1982AJ01), and ^{14}N, ^{15}N in (1981AJ01) and ^{12}C in (1980AJ01). For a discussion of the earlier work see (1978AJ03). See also (1979TU1B, 1981KR1K), (1978FI1E, 1978HO1C) and (1978ME1J, 1978ME20, 1978ME14, 1979BE59, 1979SU1F, 1981ME1E, 1981ME1F, 1981OS1D; theor.).
See (1972AJ02).
Angular distributions are reported at E(^{9}Be) = 12 to 27 MeV to ^{18}F_{g.s.} and to the unresolved states at 1 MeV (1979JA22, 1981JA09).
See (1978AJ03). The work on reaction (b) displayed there has not been published.
See (1980KO02).
See (1978PI1E).
A number of resonances have been observed for E_{α} < 3 MeV: see Table 18.14 (in PDF or PS). Studies of these, principally by the Toronto and Queen's groups [see references in (1978AJ03) and (1977BE46, 1979KI12, 1980MA26)] in conjunction with work on ^{14}N(α, α), ^{16}O(^{3}He, p), ^{17}O(p, γ) and ^{17}O(p, α) [see Tables 18.16 (in PDF or PS), 18.17 (in PDF or PS), 18.18 (in PDF or PS)] have led to the determination of branching ratios, mixing ratios and widths (Table 18.12 (in PDF or PS)), lifetimes (Table 18.13 (in PDF or PS)) and the E_{x}, J^{π} and K^{π} assignments for ^{18}F 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 lowlying states of ^{18}F. The nonresonant Sfactor for this reaction, S ≈ 0.7 MeV · b (1972CO1C). See also (1978TA1U; astrophys.).
See (1978AJ03).
Observed resonances are displayed in Table 18.14 (in PDF or PS). See also (1978AJ03).
Observed anomalies in the elastic scattering are exhibited in Table 18.14 (in PDF or PS). Resonances in the α_{1} isospinforbidden yield are displayed in Table 18.14 (in PDF or PS) of (1978AJ03). In the α_{1} study, carried out for E_{α} = 7.6  16.9 MeV, a partialwave analysis involving a method of removing ambiguities and parametrizing Smatrix elements gives the level parameters of 151 isospin mixed, naturalparity states in ^{18}F with 10.4 < E_{x} < 17.5 MeV. Many of these states have also been reported in the ^{16}O(d, α_{1}) reaction [Table 18.16 (in PDF or PS) of (1978AJ03)]. The agreement is best for lowlying 2^{+} or 4^{+} states, and is quite good for 3^{} and 5^{} states, while for highJ states the greater centrifugal barrier for ^{16}O + d at the same E_{x} relatively suppresses highJ states in the ^{16}O + 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 (1976CH24).
The total cross section for formation of ^{10}B and ^{6}Li have been studied for E_{α} = 21 to 42 MeV by (1974JA11) who discuss the astrophysical importance of these processes. For spallation studies see (1979VI05, 1980RE1B, 1981GO1E). See also (1980BA2K; theor.).
Angular distributions have been measured for E(^{6}Li) = 5.3 to 6 MeV: see (1978AJ03).
At E(^{7}Li) = 15 MeV, triton groups are observed to the known T = 0 states with E_{x} < 7.4 MeV: the T = 1 states are not excited although such transitions are not forbidden in principle, suggesting a direct αtransfer mechanism. The transitions to ^{18}F*(1.70, 2.53, 3.36, 4.23, 5.30, 6.57) account for more than onehalf of the summed cross section at 15°. It is proposed that these states (which are only weakly excited in ^{16}O(^{3}He, p)^{18}F and ^{17}O(^{3}He, d)^{18}F) are predominantly of a 4p  2h nature and are excited by the transfer of four nucleons into the (2s, 1d) shell (1968MI09). At E(^{7}Li) = 36 MeV the K^{π} = 1^{+} band also appears to be selectively populated. States at E_{x} = 9.58 ± 0.02, 11.22 ± 0.03 and 14.18 ± 0.04 MeV are strongly populated. It is suggested that the first two are the 6^{+} and 7^{+} members of that band (1977CO09). [Angular distributions are reported for ^{18}F*(1.70, 2.10, 2.52, 3.36, 4.40, 5.30, 6.57, 9.58, 11.22, 14.18).] See also (1979SA31; theor.).
These reactions have been studied at E(^{11}B) = 115 MeV and E(^{13}C) = 105 MeV. Differential cross sections at three angles are reported for the transitions to ^{18}F*(9.58, 10.57 ± 0.07, 11.2) in reaction (a) and to ^{18}F*(5.30, 6.57, 9.58, 10.60 ± 0.08, 11.2) in reaction (b). In addition to these states ^{18}F*(14.18) is strongly excited in both reactions, and transitions to ^{18}F*(15.79 ± 0.10, 18.62 ± 0.12) are also reported (1979BR04).
See (1977VO08).
Excitation functions have been measured for E(^{3}He) = 2.5 to 16 MeV for the γ_{0} and γ_{1→4} yields. Resonances are observed corresponding to E_{x} = (19.00 ± 0.15) [γ_{1→4}], 20.1 ± 0.2 [γ_{0}, γ_{1→4}], 22.7 ± 0.2 [γ_{0}, γ_{1→4}] and (24.1 ± 0.2) MeV [γ_{1→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 γ_{0} yield is dominated by ^{18}F*(20.1) (1981WA1R) [see for (2J + 1)Γ_{3He}Γ_{γ} values]. It is suggested that the structures decaying by γ_{0} have J^{π} = 2^{} (and possibly T = 1) (1981WA1R, and J. Lowe, private communication).
See ^{17}O in (1982AJ01).
See (1978AJ03).
At E(^{6}Li) = 30 MeV preferential excitation of oddparity states of ^{18}F below E_{x} = 5 MeV is reported. Angular distributions of the tritons to ^{18}F*(0, 0.94, 2.10, 4.40) [J^{π} = 1^{+}, 3^{+}, 2^{}, 4^{}] are all strongly forward peaked (1972LI24).
These reactions have been studied with E(^{11}B) = E(^{12}C) = 115 MeV. Reaction (a) is dominated by the transitions to ^{18}F*(1.12) [presumably the J^{π} = 5^{+} state, although the group is unresolved] and to ^{18}F*(7.15, 9.45) [J^{π} = (7^{}) and (6^{})]. In reaction (b) no single state is strongly preferentially populated (1979RA10, 1981GO11). Differential cross sections for ^{18}F*(4.40, 6.10, 7.15, 9.45) [J^{π} = 4^{}, (5^{}), (7^{}), (6^{})], fitted by FRDWBA, are discussed by (1981GO11). See also (1977FO1E).
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. The results can be interpreted satisfactorily in terms of compound nucleus formation (1965OW01).
Excitation functions have been measured for the n_{0} and n_{1} groups from threshold to 17 MeV: see (1978AJ03). Some structure is observed: that which is attributed to states of ^{18}F is displayed in Table 18.15 (in PDF or PS). Polarization measurements are reported for E_{d} = 3 to 15 MeV: see (1978AJ03) and at E_{dbar} = 5 to 15 MeV (1981LI23; pol. n_{0+1}). See also ^{17}F in (1982AJ01), (1980HU1J, 1980HU1D) and (1981NO1B).
Excitation functions and polarization studies have been reported for several proton groups for E_{d} = 0.3 to 17 MeV: see (1978AJ03) and (1978RO1M; E_{dbar} = 14 to 17 MeV). Some of the maxima in the yield measurements are interpreted in terms of resonances: these are shown in Table 18.15 (in PDF or PS). See also ^{17}O in (1982AJ01).
The yield of elastically scattered deuterons and elastic polarization measurements have been reported for E_{d} = 0.65 to 56 MeV: see (1978AJ03) and (1982AOZZ; E_{d} = 13.8 to 16.5 MeV), (1981FR1C; TAP; E_{dbar} = 20 MeV), (1981CL1C; VAP; E_{dbar} = 20.5 MeV; also to ^{16}O*(6.13)), (1980MA10; VAP; E_{dbar} = 52 MeV), (1980HA14; VAP; E_{dbar} = 56 MeV). For total cross sections at high energies see (1979DE31). See also ^{16}O in (1982AJ01), (1978RO1M) and (1979NI1B, 1980AY01, 1981AO01, 1982YA1A; theor.).
Vector analyzing powers have been studied at E_{dbar} = 29 MeV (1978CO13: to ^{15}N*(0, 6.32) and ^{15}O*(0, 6.18)) and 52 MeV (1977BE70: to ^{15}N*(0, 6.32, 9.94, 10.71)). See also (1978AJ03) and (1981MA14).
The yields of various groups of αparticles have been measured for E_{d} ≤ 20 MeV: see (1978AJ03) and (1979MA2Q; 0.65 to 1.1 MeV; α_{0}), (1978RI05; 6.7 to 12.5 MeV; α_{3}) and (1982AOZZ; 13.8 to 16.5 MeV; α_{0}). The yield curves have been fitted in terms of a large number of states in ^{18}F: see Tables 18.15 (in PDF or PS) here and 18.16 (in PDF or PS) in (1978AJ03). A detailed study by (1973JO13) of the isospinforbidden α_{1} yield, analyzed by Smatrix theory, identifies a large number of isospin mixed states in ^{18}F, 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 Fermigas model (1973JO13). See also (1981JO1D). [For mixed isospin states observed in ^{14}N(α, α_{1}) see Table 18.14 (in PDF or PS) in (1978AJ03)]. Polarization measurements are reported for E_{d} = 6.8 to 16 MeV: see (1978AJ03). The T_{21} analyzing power of the transition to ^{14}N*(4.91) [0^{}] has been measured at E_{d} = 8.06 MeV (θ = 45°) to 0.5% (1981KA21). See also (1979TO1A, 1980PR1A, 1981TO1G), (1979MA2Q: applications), (1978SE01, 1979SE04; theor.) and ^{14}N in (1981AJ01).
See (1978AJ03).
See (1978AJ03). See also (1976HE1N) and (1980KU1H; applied).
Excitation energies derived from measurements of γrays are displayed in Table 18.16 (in PDF or PS), together with lassignments obtained from distortedwave analyses, and J^{π}; T and K^{π} assignments from branching ratios, radiative widths, linear polarization, γray angular distributions and τ_{m} measurements [see also Tables 18.12 (in PDF or PS) and 18.13 (in PDF or PS)]. Studies of this reaction, together with the work on ^{14}N(α, γ) and ^{17}O(p, γ), have defined the lowlying states of ^{18}F. The gfactor of ^{18}F*(0.94) [J^{π} = 3^{+}] is +0.54 ± 0.06 (1981ST21), 0.58 ± 0.07 (1978GO1T). τ_{m} of ^{18}F*(1.04) = 2.7 ± 0.7 fsec. The weighted mean "best" value [see Table 18.12 (in PDF or PS)] is 2.7 ± 0.4 fsec. This leads to M^{2} = 10.3 ± 1.5 W.u., and using the E1 strength of the ^{18}F*(1.08 → g.s.) decay leads to a value for the circular polarization of the 1.08 → g.s. γray [P_{γ}] [0^{}; T = 0 to 1^{+}; 0] = ± (5.8 ± 0.4) keV^{1}< 1.04V^{PNC}1.08 > (1981KE04). The experimental value for P_{γ} = (0.7 ± 2.0) × 10^{3} (1978BA08). (1981AD1E) reports a best value of P_{γ} = (0.1 ± 1.2) × 10^{3}. The importance of the decays of ^{18}F*(1.04, 1.08) [J^{π} = 0^{+}, T = 1; J^{π} = 0^{}, T = 1, respectively] lies in testing the parity nonconserving (PNC) component of nuclear forces: see also (1980BI11), (1981HA1H) and (1980HA41; theor.). The magnetic moment of ^{18}F*(1.13) = +2.855 ± 0.030 nm, in agreement with shellmodel predictions for a (1d^{2}_{5/2})_{5+} state: see (1978AJ03). See also (1979HA1M), (1977FI13, 1980HE06; applied) and ^{19}Ne.
Angular distributions of the deuteron groups to ^{18}F*(1.12) [J^{π} = 5^{+}] have been studied at E_{α} = 28.0 to 33.6 MeV (1978CO10, 1979CO1P). See also ^{20}Ne and (1972AJ02).
Angular distributions for α_{0} are reported at E(^{6}Li) = 5.5 to 13.3 and 26 MeV: see (1978AJ03). At E(^{6}Li) = 34 MeV angular distributions are reported to ^{18}F*(0, 0.94, 1.1 [unres.]) and forward angle data has been obtained for ^{18}F*(2.10, 3.72, 3.79, 3.84). The angular distributions for the first three groups are forward peaked and show little structure at back angles. ^{18}F*(1.04, 3.06) are not observed, as expected from isospin conservation. States at E_{x} = 4.12, 4.23, 4.4, 5.61, 6.11, 6.20, 6.53, 6.80 and 6.88 were populated (1976MO24). See also (1981MA26; theor.).
Forward angle differential cross sections are reported at E(^{11}B) = 115 MeV to ^{18}F*(1.1) [J^{π} = 3^{+} + 5^{+}] and to ^{18}F*(4.65) [J^{π} = 4^{+}] (1980PR09). See also (1979RA10).
Forward angle differential cross sections are reported at E(^{13}C) = 105 MeV ^{18}F*(1.12, 4.65) (1980PR09). For reaction (a) see (1978AJ03).
Angular distributions are reported at E(^{14}N) = 76.2 MeV to ^{18}F_{g.s.} (1977MO1A).
See (1978AJ03).
Gammaray measurements lead to the very accurate E_{x} determinations for ^{18}F states below 6.2 MeV: see Table 18.17 (in PDF or PS). Observed resonances are displayed in Table 18.18 (in PDF or PS); branching ratios, radiative widths and multipole mixing ratios are shown in Table 18.12 (in PDF or PS); and τ_{m} in Table 18.13 (in PDF or PS). The direct capture cross section has been studied for E_{p} = 0.3 to 1.9 MeV: ^{18}F*(5.603, 5.605, 5.668, 5.786) have J^{π} = 1^{+}, 1^{}, 1^{} and 2^{}. The 1^{} states have mixed isospin. Astrophysical considerations are discussed in (1978AJ03) and (1975ZI1A, 1977RO1H, 1978RO1D).
Observed resonances are displayed in Table 18.18 (in PDF or PS). See also (1978AJ03).
The elastic scattering has been studied for E_{p} = 0.5 to 13 MeV [see (1978AJ03)] and 1.4 to 3.0 MeV (1977SE12, 1978SE08): observed anomalies are displayed in Table 18.18 (in PDF or PS).
See (1978AJ03).
The yield of α_{0} shows a number of resonances for E_{p} = 0.49 to 3.0 MeV: see Table 18.18 (in PDF or PS). The Rmatrix 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 ^{17}O is burned up in the (p, γ) rather than in the (p, α) reaction for a wide range of stellar temperatures (1979KI13). See also (1977RO1H, 1978RO1D; astrophys.).
See (1972AJ02).
At E(^{3}He) = 15 MeV, DWBA analysis of angular distributions of deuteron groups corresponding to the ground state of ^{18}F [l = 2] and to the excited states at 0.94 [l = 0 + 2], 1.04 [2], 1.12 [2], 2.53 [0 + 2], 3.06 [0 + 2], 3.84 [0 + 2], 4.12 [0 + 2], 4.66 [2] and 4.96 [l = 0 + 2] have been obtained by (1969PO11) who also report spectroscopic information. Thus all these states have even parity and ^{18}F*(4.11) may be assigned J^{π} = (2^{+}) or 3^{+}. Since l = 2 for ^{18}F*(4.65), J^{π} ≤ 5^{+}, with 4^{+} most likely (1969PO11). See also (1979SA31; theor.).
Forward angle differential cross sections are reported for the transition to ^{18}F*(1.12) at E(^{12}C) = 115 MeV (1980PR09).
Angular distributions of a number of neutron groups are reported for E_{p} = 5.5 to 13.5 MeV: see (1978AJ03). The τ_{m} of ^{18}F*(1.04) [J^{π} = 0^{+}; T = 1] is 2.7^{+0.6}_{0.4} fsec (1980KE05): see Table 18.13 (in PDF or PS). See also ^{19}F.
At E(^{3}He) = 16 MeV, the triton spectrum is dominated by strong groups to the ground and 0.94 MeV excited states and to the 0^{+} and 2^{+}, T = 1 states at E_{x} = 1.04 and 3.06 MeV. Angular distributions have been measured and analyzed by DWBA for the tritons corresponding to these states and to ^{18}F*(1.08, 1.12, 1.70, 2.10, 3.13, 3.36, 3.72, 3.79, 3.84, 4.12, 4.23, 4.36, 4.40, 4.65, 4.75). The angular distributions are consistent with the J^{π} assignments shown in Table 18.11 (in PDF or PS), except for the distribution to ^{18}F*(1.04) (1970DU08). At E(^{3}He) = 17.3 MeV, angular distributions to ^{18}F states with E_{x} < 4 MeV have been analyzed using DWBA and a twobody interaction between the incident and target nucleons. An exact coupledchannel calculation was also made for the transition to ^{18}F*(1.04) (1968HA30). At E(pol. ^{3}He) = 33 MeV the analyzing power angular distribution for t_{0} has been measured by (1981BA1G).
At E(^{6}Li) = 34 MeV angular distributions have been obtained for the transitions to ^{18}F*(0, 0.94): there appears to be a sizeable contribution due to twostep processes: see (1978AJ03).
The halflife of ^{18}Ne is 1672 ± 4 msec (see ^{18}Ne). The decay is to ^{18}F*(0, 1.04, 1.08, 1.70): see Table 18.19 (in PDF or PS) for the branching ratios and log ft values.
Cross sections to 30 MeV for the transitions to ^{18}F*(0.94, 1.04, 1.08, 3.06, 3.13, 4.75) are reported by (1979TH05). See also (1978AJ03), (1980YA08; applied) and ^{19}F.
See (1978CO18, 1980CO1U). See also ^{20}F and (1978AJ03).
Angular distributions of the d_{0} group have been measured at E_{p} = 16 to 155.6 MeV: l_{n} = 0: see (1972AJ02) and (1977GU14: 17.7 MeV). At E_{p} = 19.3 MeV angular distributions are also reported to excited states of ^{18}F: see Table 18.20 (in PDF or PS). The angular distributions associated with 0h  2p states in ^{18}F are only qualitatively accounted for by DWBA. Those corresponding to 1h  3p negativeparity states generally cannot be accounted for by a singlestep mechanism, while the distributions to states arising from 2p  4h configurations do not show the features associated with direct interaction (1980DE05). See also (1982MA1H) and (1978AJ03).
Angular distributions of triton groups have been reported at E_{d} = 8.9 (t_{0}, t_{1}, t_{3}) and 14.8 MeV (t_{0}): see (1972AJ02). See also (1978AJ03).
Many αparticle groups have been observed [see Table 18.21 (in PDF or PS) in (1978AJ03)].
See (1972AJ02).
At E_{p} = 45 MeV, ^{18}F*(0, 1.04, 1.70, 3.06, 6.27) are populated: see (1978AJ03).
At E_{d} = 11 MeV αgroups are observed to many states of ^{18}F with E_{x} < 7 MeV. Weak or absent (each ≤ 0.3% of the total yield at 30°) are the groups corresponding to ^{18}F*(1.04, 3.06, 4.66, 4.74, 4.96): T = 1 for these states (1969PO11). Angular distributions at E_{d} = 6.66, 7.29, 7.93 and 12.95 MeV have been obtained for the αgroups to ^{18}F*(2.10 [not 12.95 MeV], 2.52, 3.06 [2^{+}; 1], 3.13, 3.36, 4.12). The ratio of the total cross section for the isospinforbidden transition to ^{18}F*(3.06) to the total cross section of four T = 0 states ranges from 6% to 40%. The average is 21% suggesting isospin mixing in the compound nucleus: the yield curves show strong structures particularly in the range 5 to 9 MeV (1973HR03). Angular distributions have also been measured at E_{d} = 2 to 14.7 MeV: see (1978AJ03). Measurements of the tensor analyzing power for E_{dbar} = 10.25 to 12.0 MeV leads to assignments of unnatural parity for ^{18}F*(0, 0.94, 1.08 + 1.12, 1.70, 2.10, 3.36, 3.72, 4.12, 4.23, 4.36, 4.40, 5.603 + 5.605 + 5.67, 5.79, 6.10 + 6.10, 6.14 + 6.16, 6.31, 6.48) and to natural parity for ^{18}F*(3.79, 3.84, 4.86): assignments of J^{π} = 2^{}, 1^{+}, 0^{+}, 1^{}, 1^{+}, 3^{+}, 3^{+} are made for ^{18}F*(4.23, 4.36, 4.75, 4.86, 5.603, 6.16, 6.48) [all T = 0 except ^{18}F*(4.75)] (1978DA02).
See (1979LE1R, 1980LE21; theor.).
See (1978NO02).
