(See Energy Level Diagrams for 17F)
Complex reactions involving 17F: ( 1977AR06).
Q = 0.10 ± 0.02 b (1974MI21).
Two recent measurements of the half-life of 17F 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 17O*(0.87) is < 3.4 × 10-4 per decay (1969GA05) [log ft > 5.6]. See also (1978RA2A) and (1977AZ02, 1978BR1R, 1979BA08, 1979OS1E, 1979TO1B; theor.).
Excitation functions for γ0, γ1, γ2 and γ3 have been studied for E(3He) = 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 γ0+1 yield at 90°, indicated several sharp resonances].
Excitation functions for protons have been measured for E(3He) = 2.5 to 18 MeV [see (1977AJ02)]: some large structures are observed. The polarization of the p0 group has been studied at E(3He) = 9.8 MeV. The elastic scattering of 3He (reaction (d)) and the yield of α-particles (reaction (e)), studied in the ranges E(3He) = 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 16O and 16F here, and 13N, 14N and 15O in (1981AJ01).
See 18F in (1978AJ03).
Angular distributions have been reported to most of the states of 17F with Ex < 8.1 MeV at E(3He) = 3.8 and 4.8 MeV: see (1977AJ02). Neutron groups have also been reported to 17F states at Ex = 11.195 ± 0.007, 12.540 ± 0.010 and 13.059 MeV, with Γ < 20, < 25 and < 25 keV, respectively. Angular distributions at E(3He) = 10.36 and 11.88 MeV lead to Jπ = 1/2- for 17F*(11.20) [L = 0], 3/2- or 5/2- for 17F*(12.54) and (3/2-, 5/2-) for 17F*(13.06). These three states are probably the first three T = 3/2 states in 17F (1969AD02). The branching ratios for transitions to 16O*(0, 6.05, 6.13) for 17F*(11.20) and for the analog T = 3/2 state in 17O 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(11B) = 115 MeV 17F*(0, 5.22) are strongly populated (1979RA10).
At low energies the direct capture to 17F*(0, 0.50) is observed: see (1971AJ02, 1977AJ02). Extrapolation of cross-section 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 γ1 and γ0 + γ1 yields: see Table 17.20 (in PDF or PS) for the reported parameters. The lowest T = 3/2 states of even parity at Ex = 13.27 and 14.02 MeV [Jπ = (1/2+) and 5/2+] (see Table 17.21 (in PDF or PS)) are not observed here: Γγ ≤ 7 and ≤ 11.8 eV, respectively (1975HA06). The (E1) values for the T = 3/2 states are in good agreement with shell model 2p-1h calculations using realistic Kuo-Brown interaction matrix elements (1975HA06).
The (γ0 + γ1) yield at 90° has been studied for Ep = 15.75 to 31.66 MeV: it shows the giant dipole resonance centered at Ex = 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 2p-1h, 1p excitation calculations. The pigmy resonance is due to f7/2 → d5/2: the main f7/2 strength lies in two states at Ex = 16.9 and 18.0 MeV (1975HA07). See also (1979BL1F), (1981CA1D), (1975ZI1A; astrophys.) and (1977AL18; theor.).
Yield curves for elastic protons, protons scattered to 16O*(6.05, 6.13, 6.92, 7.12, 8.87) and for γ-rays from 16O*(6.13, 6.92) have been studied at many energies up to Ep = 46 MeV: see Table 17.19 (in PDF or PS) in (1971AJ02) and (1977AJ02) for the earlier work and (1981KR1B; Ep-bar = 8.5 to 10.6 MeV; p0), (1979DA11; Ep-bar ≈ 14.4 MeV; p0). The observed resonances are displayed in Table 17.21 (in PDF or PS).
Polarization results have been reported at Ep = 3.47 to 49.4 MeV [see (1977AJ02)] and at Ep = 40 MeV (1978MO14; p5), 42.5, 44.0 and 49.3 MeV (1977PE09; p5), 65 MeV (1979SA38, 1981SA1F; p0), 135 MeV (1980KE14; p2, p4), 800 MeV (1979AD03, 1979GL1C; p0, p1+2, p3, p4, p5) and 1 GeV (1978AL1G, 1978AL1X, 1980AL09). For total reaction cross sections see (1979DE31, 1981DY03). See also (1977AJ02).
Polarization in quasi-elastic scattering (reaction (b)) has been studied at Ep = 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 16O 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.).
The excitation function for d0 (θ = 70°) has been measured for Ep = 21 to 38.5 MeV. A strong resonance is observed at Ep = 24 MeV: see Table 17.21 (in PDF or PS). Polarization measurements are reported at Ep = 65 MeV (1981HO1L; d0), 30.3 MeV [see (1977AJ02)] and Epol. p = 200 MeV (1981LI1B). See also 15O in (1981AJ01) and (1979CA1A).
The excitation function (θ = 70°) for tritons has been measured for Ep = 32 to 39.5 MeV: no structure is observed [see (1977AJ02)]. Differential cross sections and analyzing powers have been studied at Ep = 43.8 MeV for the transitions to 14O*(0, 5.17, 6.29, 6.59, 7.78, 9.72) and 14N*(0, 2.31, 3.95, 5.11, 7.03, 9.17): attemts to fit the analyzing powers with zero-range DWBA were only successful for the first pair of analog states [14Og.s., 14N*(2.31)] (1974MA12). For other polarization measurements see (1977AJ02). See also 14N and 14O in (1981AJ01) and (1977HA1P).
Excitation functions of various α-groups and activation functions have been measured from threshold to Ep = 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; σt). Observed resonances are displayed in Table 17.21 (in PDF or PS). Some broad structures have been reported above Ep ≈ 15 MeV; particularly strong peaks appear at Ep ≈ 22 and 25.5 MeV: see (1977AJ02).
Slow neutron thresholds have been observed corresponding to the ground and first excited states of 17F: see (1971AJ02). The Ex of 17F*(0.50) is 495.33 ± 0.10 keV (1966AL10; from γ-measurement); τm = 407 ± 9 psec (1964BE15). Neutron groups have been observed corresponding to 17F*(0, 0.50, 3.10, 3.86, 4.70). Angular measurements have been obtained for the n0 and n1 groups (lp = 2 and 0, respectively: Jπ = 5/2+ and 1/2+) for Ed ≤ 12 MeV: see Table 17.21 (in PDF or PS) in (1971AJ02) and (1972AN21; Ed = 3.10, 3.40 and 3.66 MeV). For polarization measurements see 18F in (1983AJ01). See also (1980HU1J) and (1977AJ02).
At E(3He) = 18 MeV, angular distributions of the deuterons to 17F*(0, 0.50, 3.104 ± 0.003, 3.857 ± 0.004) have been measured. The spectroscopic factors for 17F*(0, 0.50) are 0.94 and 0.83. Two-step processes appear to be involved in the excitation of 17F*(3.10, 3.86) (1975FO16). Angular distributions have also been measured at E(3He) = 30 MeV (1977KO2H; to 17F*(5.1, 5.7) and at E(pol. 3He) = 33 MeV (1980LU03, 1981RO1H; d0, d1). See also 19Ne in (1983AJ01) and (1977COZZ; theor.).
The angular distribution involving 17Fg.s. has been measured at E(7Li) = 36 MeV (1973SC26).
Angular distributions of the n0 and n1 groups have been obtained for Ep = 6.95 to 13.50 MeV (n0) and 6.95 to 12.45 MeV (n1). There appears to be collective enhancement in the L = 2 transition to 17F*(0.5). A large spin-flip term in the effective two-body force is necessary to account for the strength of the ground state transition (1969AN06). See also 18F in (1983AJ01).
See 19F in (1983AJ01).
Angular distributions have been measured for the t0 → t3 groups at Ep = 22.8, 42.4 and 45 MeV: see (1977AJ02).
At E(3He) = 75 and 88 MeV 17F*(0, 0.5) have been populated in both reactions (1978KE06).