
^{17}F (1982AJ01)(See Energy Level Diagrams for ^{17}F) GENERAL: See (1977AJ02) and Table 17.18 [Table of Energy Levels] (in PDF or PS). Shell and cluster models: (1977DU04, 1977HA1Z, 1977PO16, 1978TH1A). Special states: (1977HE18, 1978EN1D, 1980CH35, 1981TA09). Electromagnetic transitions: (1976MC1G, 1977BR03, 1977HA1Z, 1977HO04, 1980CH35). Complex reactions involving ^{17}F: ( 1977AR06). Astrophysical questions: (1977SI1D, 1979WO07). Reactions involving pions: (1981OS04, 1981PU1A). Other topics: (1976SA1H, 1977BA3P, 1978EN1D, 1978SH1B, 1978SL1B, 1979BE1H, 1981TA09). Ground state of ^{17}F: (1976JO1B, 1976MC1G, 1976SA1H, 1977AN12, 1977BR03, 1977DU04, 1977HA1Z, 1977KO28, 1977PO16, 1977SH13, 1978AR1R, 1978SL1B, 1980CH35, 1981TA09).
Q = 0.10 ± 0.02 b (1974MI21).
Two recent measurements of the halflife of ^{17}F are 64.31 ± 0.09 sec (1977AZ01) and 64.80 ± 0.12 sec (1977AL20): the weighted mean of these is 64.49 ± 0.16 sec; log ft = 3.36. Earlier values are listed in (1971AJ02, 1977AJ02). The upper limit for the β^{+} decay to ^{17}O*(0.87) is < 3.4 × 10^{4} per decay (1969GA05) [log ft > 5.6]. See also (1978RA2A) and (1977AZ02, 1978BR1R, 1979BA08, 1979OS1E, 1979TO1B; theor.).
See (1971AJ02).
Angular distributions are reported to ^{17}F*(0, 0.50) at E(^{14}N) = 53 MeV (1976ZE04) and 78.8 MeV (1977MO1A; unresolved).
See (1979OR01).
Excitation functions for γ_{0}, γ_{1}, γ_{2} and γ_{3} have been studied for E(^{3}He) = 3 to 19 MeV: observed resonances are displayed in Table 17.19 (in PDF or PS) (1981WA1R). [The earlier work by (1972MO39), who studied the γ_{0+1} yield at 90°, indicated several sharp resonances].
Excitation functions for protons have been measured for E(^{3}He) = 2.5 to 18 MeV [see (1977AJ02)]: some large structures are observed. The polarization of the p_{0} group has been studied at E(^{3}He) = 9.8 MeV. The elastic scattering of ^{3}He (reaction (d)) and the yield of αparticles (reaction (e)), studied in the ranges E(^{3}He) = 4 to 7 MeV and 2.5 to 8.5 MeV, respectively, show some evidence of structures (1970KN01, 1972MO39): see the disucssion in (1977AJ02). See also ^{16}O and ^{16}F here, and ^{13}N, ^{14}N and ^{15}O in (1981AJ01).
See ^{18}F in (1978AJ03).
At E(^{6}Li) = 18 MeV ^{17}F*(3.86, 5.22 ± 0.01, 5.67 + 5.68) are strongly excited. J^{π} = 9/2^{} is suggested for ^{17}F*(5.22) (1973BI01). See also (1977MA2G).
See (1977AJ02).
Angular distributions have been reported to most of the states of ^{17}F with E_{x} < 8.1 MeV at E(^{3}He) = 3.8 and 4.8 MeV: see (1977AJ02). Neutron groups have also been reported to ^{17}F states at E_{x} = 11.195 ± 0.007, 12.540 ± 0.010 and 13.059 MeV, with Γ < 20, < 25 and < 25 keV, respectively. Angular distributions at E(^{3}He) = 10.36 and 11.88 MeV lead to J^{π} = 1/2^{} for ^{17}F*(11.20) [L = 0], 3/2^{} or 5/2^{} for ^{17}F*(12.54) and (3/2^{}, 5/2^{}) for ^{17}F*(13.06). These three states are probably the first three T = 3/2 states in ^{17}F (1969AD02). The branching ratios for transitions to ^{16}O*(0, 6.05, 6.13) for ^{17}F*(11.20) and for the analog T = 3/2 state in ^{17}O are displayed in Table 17.11 (in PDF or PS): the ratios of the reduced widths are quite different in the two mirror nuclei (1970MC02, 1973AD02).
At E(^{11}B) = 115 MeV ^{17}F*(0, 5.22) are strongly populated (1979RA10).
At low energies the direct capture to ^{17}F*(0, 0.50) is observed: see (1971AJ02, 1977AJ02). Extrapolation of crosssection data leads to S(0) ≈ 8 keV · b: see (1977AJ02). In addition to two T = 1/2 resonances, five resonances corresponding to T = 3/2 states are observed in the γ_{1} and γ_{0} + γ_{1} yields: see Table 17.20 (in PDF or PS) for the reported parameters. The lowest T = 3/2 states of even parity at E_{x} = 13.27 and 14.02 MeV [J^{π} = (1/2^{+}) and 5/2^{+}] (see Table 17.21 (in PDF or PS)) are not observed here: Γ_{γ} ≤ 7 and ≤ 11.8 eV, respectively (1975HA06). The (E1) values for the T = 3/2 states are in good agreement with shell model 2p1h calculations using realistic KuoBrown interaction matrix elements (1975HA06). The (γ_{0} + γ_{1}) yield at 90° has been studied for E_{p} = 15.75 to 31.66 MeV: it shows the giant dipole resonance centered at E_{x} = 22 MeV with a width of ≈ 5 MeV and a pigmy resonance centered at 17.5 MeV. The integrated strength of the, mainly T = 1/2, giant resonance is 10 MeV · mb: the observed strength distribution is on good agreement with odd parity 2p1h, 1p excitation calculations. The pigmy resonance is due to f_{7/2} → d_{5/2}: the main f_{7/2} strength lies in two states at E_{x} = 16.9 and 18.0 MeV (1975HA07). See also (1979BL1F), (1981CA1D), (1975ZI1A; astrophys.) and (1977AL18; theor.).
Yield curves for elastic protons, protons scattered to ^{16}O*(6.05, 6.13, 6.92, 7.12, 8.87) and for γrays from ^{16}O*(6.13, 6.92) have been studied at many energies up to E_{p} = 46 MeV: see Table 17.19 (in PDF or PS) in (1971AJ02) and (1977AJ02) for the earlier work and (1981KR1B; E_{pbar} = 8.5 to 10.6 MeV; p_{0}), (1979DA11; E_{pbar} ≈ 14.4 MeV; p_{0}). The observed resonances are displayed in Table 17.21 (in PDF or PS). Polarization results have been reported at E_{p} = 3.47 to 49.4 MeV [see (1977AJ02)] and at E_{p} = 40 MeV (1978MO14; p_{5}), 42.5, 44.0 and 49.3 MeV (1977PE09; p_{5}), 65 MeV (1979SA38, 1981SA1F; p_{0}), 135 MeV (1980KE14; p_{2}, p_{4}), 800 MeV (1979AD03, 1979GL1C; p_{0}, p_{1+2}, p_{3}, p_{4}, p_{5}) and 1 GeV (1978AL1G, 1978AL1X, 1980AL09). For total reaction cross sections see (1979DE31, 1981DY03). See also (1977AJ02). Polarization in quasielastic scattering (reaction (b)) has been studied at E_{p} = 200 MeV by (1976KI10, 1980KI06) and 635 MeV (1977NA29, 1978NA18). For reactions (c) and (d) see (1977AJ02). For reaction (d) see (1981DY03). For spallation measurements see (1976IN04, 1977MO1C) and (1979VD02). For antiproton scattering see (1981AU01; theor.). See also ^{16}O and (1978GO05, 1978SA33, 1979WI1N, 1979WIZX, 1980LE28), (1979RA1C; astrophys.), (1977PL1A, 1979DE1P, 1979VO08, 1980MC1C, 1980WH1A, 1981RA1B) and (1976JE1A, 1976LE26, 1977KO2G, 1977PH02, 1978AB08, 1978AL07, 1978BI1L, 1978BR28, 1978GR1D, 1978PH01, 1978RE1G, 1978SC14, 1978WU03, 1979BI1C, 1979CH2C, 1979ER02, 1979KO01, 1979MA48, 1979PH05, 1979RA27, 1980AU09, 1980AY01, 1980DE2F, 1980DM1A, 1980MA28, 1980MA06, 1980RA1B, 1981DE2J; theor.).
For analyzing power measurements see ( 1981MA1J, 1981MAZW; E_{pol. p} = 135 MeV). See also ^{16}F.
The excitation function for d_{0} (θ = 70°) has been measured for E_{p} = 21 to 38.5 MeV. A strong resonance is observed at E_{p} = 24 MeV: see Table 17.21 (in PDF or PS). Polarization measurements are reported at E_{p} = 65 MeV (1981HO1L; d_{0}), 30.3 MeV [see (1977AJ02)] and E_{pol. p} = 200 MeV (1981LI1B). See also ^{15}O in (1981AJ01) and (1979CA1A).
The excitation function (θ = 70°) for tritons has been measured for E_{p} = 32 to 39.5 MeV: no structure is observed [see (1977AJ02)]. Differential cross sections and analyzing powers have been studied at E_{p} = 43.8 MeV for the transitions to ^{14}O*(0, 5.17, 6.29, 6.59, 7.78, 9.72) and ^{14}N*(0, 2.31, 3.95, 5.11, 7.03, 9.17): attemts to fit the analyzing powers with zerorange DWBA were only successful for the first pair of analog states [^{14}O_{g.s.}, ^{14}N*(2.31)] (1974MA12). For other polarization measurements see (1977AJ02). See also ^{14}N and ^{14}O in (1981AJ01) and (1977HA1P).
Excitation functions of various αgroups and activation functions have been measured from threshold to E_{p} = 44 MeV: see Table 17.19 (in PDF or PS) in (1971AJ02) and (1977AJ02) for the earlier work and (1977GR17; 6.6 to 10.4 MeV; σ_{t}). Observed resonances are displayed in Table 17.21 (in PDF or PS). Some broad structures have been reported above E_{p} ≈ 15 MeV; particularly strong peaks appear at E_{p} ≈ 22 and 25.5 MeV: see (1977AJ02). This reaction is involved in explosive burning in stars: see (1977AJ02) for earlier work and (1977GR17; S_{0} = 4 ± 3 b at E_{p}(cm) = 6.5 MeV). See also (1977CL1F).
Slow neutron thresholds have been observed corresponding to the ground and first excited states of ^{17}F: see (1971AJ02). The E_{x} of ^{17}F*(0.50) is 495.33 ± 0.10 keV (1966AL10; from γmeasurement); τ_{m} = 407 ± 9 psec (1964BE15). Neutron groups have been observed corresponding to ^{17}F*(0, 0.50, 3.10, 3.86, 4.70). Angular measurements have been obtained for the n_{0} and n_{1} groups (l_{p} = 2 and 0, respectively: J^{π} = 5/2^{+} and 1/2^{+}) for E_{d} ≤ 12 MeV: see Table 17.21 (in PDF or PS) in (1971AJ02) and (1972AN21; E_{d} = 3.10, 3.40 and 3.66 MeV). For polarization measurements see ^{18}F in (1983AJ01). See also (1980HU1J) and (1977AJ02).
At E(^{3}He) = 18 MeV, angular distributions of the deuterons to ^{17}F*(0, 0.50, 3.104 ± 0.003, 3.857 ± 0.004) have been measured. The spectroscopic factors for ^{17}F*(0, 0.50) are 0.94 and 0.83. Twostep processes appear to be involved in the excitation of ^{17}F*(3.10, 3.86) (1975FO16). Angular distributions have also been measured at E(^{3}He) = 30 MeV (1977KO2H; to ^{17}F*(5.1, 5.7) and at E(pol. ^{3}He) = 33 MeV (1980LU03, 1981RO1H; d_{0}, d_{1}). See also ^{19}Ne in (1983AJ01) and (1977COZZ; theor.).
The angular distribution involving ^{17}F_{g.s.} has been measured at E(^{7}Li) = 36 MeV (1973SC26).
Angular distributions have been measured at E(^{10}B) = 100 MeV for the transitions to ^{17}F*(0 + 0.50, 5.1, 8.1), (1975NA15), and at E(^{11}B) = 115 MeV for the transition to ^{17}F_{g.s.} (1979RA10).
Angular distributions have been measured at E(^{12}C) = 76.8 MeV (1977MO1A, 1979MO14; ^{17}F*(0, 0.5)) and at E(^{13}C) = 105 MeV (1979RA10; ^{17}F_{g.s.}).
Angular distributions involving ^{17}F*(0, 0.5) have been measured at E(^{14}N) = 76.2 MeV (1977MO1A, 1979MO14) and 155 MeV (1975NA15, 1976NA09).
Angular distributions involving ^{17}F*(0 + 0.5) have been measured at E(^{16}O) = 95.2 MeV (1977MO1A, 1979MO14).
Angular distributions of the n_{0} and n_{1} groups have been obtained for E_{p} = 6.95 to 13.50 MeV (n_{0}) and 6.95 to 12.45 MeV (n_{1}). There appears to be collective enhancement in the L = 2 transition to ^{17}F*(0.5). A large spinflip term in the effective twobody force is necessary to account for the strength of the ground state transition (1969AN06). See also ^{18}F in (1983AJ01).
Angular distributions have been studied for t_{0} and t_{1} at E(^{3}He) = 17.3 MeV [see (1977AJ02)] and for t_{0} at E(pol. ^{3}He) = 33 MeV (1981BA1G).
See ^{17}Ne.
See ^{19}F in (1983AJ01).
Angular distributions have been measured for the t_{0} → t_{3} groups at E_{p} = 22.8, 42.4 and 45 MeV: see (1977AJ02).
See (1977GR17, 1980KO1Q) and (1977AJ02).
At E(^{3}He) = 75 and 88 MeV ^{17}F*(0, 0.5) have been populated in both reactions (1978KE06).
