
^{15}N (1991AJ01)(See Energy Level Diagrams for ^{15}N) GENERAL: See also (1986AJ01), 2 [Electromagnetic Transitions in A = 1315] (in PDF or PS), 15.4 [Table of Energy Levels] (in PDF or PS) and 15.5 [Radiative decays in ^{15}N] (in PDF or PS). Nuclear models:(1985KW02, 1985PH01, 1987KA09, 1987KI1C, 1987ME1D, 1987ST05, 1988WO04, 1989WO1E, 1990VA01). Special states:(1985AR1H, 1985GO1A, 1985PH01, 1985SH24, 1987KI1C, 1987ST05, 1988KW02, 1988ZH1B, 1989OR02). Electromagnetic transitions and giant resonances:(1985BL20, 1985GO1A, 1986ER1A, 1987KI1C, 1987ST05, 1989ASZZ). Astrophysical questions:(1982BU1A, 1982CA1A, 1982WO1A, 1985PR1D, 1986FR1G, 1987AR1C, 1987AU1A, 1987LE1J, 1987ZI1C, 1988FE1A, 1988KR1G, 1988PI1C, 1988WA1I, 1989CH1X, 1989GU1Q, 1989GU1J, 1989GU1L, 1989JI1A, 1989KA1K, 1989KE1D, 1989ME1C, 1989NO1A, 1989WY1A, 1989YO1H, 1990HA1W, 1990RA1O). Complex reactions involving ^{15}N:(1985AR1H, 1985BE40, 1985HA1N, 1985PO11, 1985SI19, 1985UT01, 1986AI1A, 1986CH2G, 1986CO1Q, 1986GR1A, 1986HA1B, 1986MA13, 1986MA19, 1986ME06, 1986PO06, 1986PO15, 1986SA30, 1986SC28, 1986SO10, 1986TO10, 1986UT01, 1986VA23, 1987BA38, 1987BE1I, 1987BU07, 1987FE1A, 1987MI27, 1987NA01, 1987OL1A, 1987RI03, 1987ST01, 1987VI02, 1988AR1D, 1988GO11, 1988JO1B, 1988SA19, 1988UT02, 1989BA92, 1989GE11, 1989GRZQ, 1989KI13, 1989PA06, 1989SA10, 1989TE02, 1989YO02, 1990DA03, 1990GL01, 1990WE14). Applied work:(1986AM1B, 1986CO1Q, 1986EN1A, 1986HE1F, 1986LE1L, 1986NO1C, 1986SA41, 1986ST1K, 1987SI1D, 1988GR1A, 1988PI12, 1988PR1D, 1988VI1A, 1989KU1P, 1989TA1Y, 1989YO1H, 1990AM1F). Pion capture and reactions (See also reactions 1915, 43, and 46.): (1985LE1E, 1985MA1K, 1986BA1C, 1986SI11, 1987KA09, 1987LE1B, 1988LI23, 1988MI1K, 1988RO1M, 1988TA21, 1989CH31, 1989GE10, 1989JO07, 1989LE1L, 1990ER03, 1990OD1A, 1990TA1K). Reactions involving other mesons and hyperons:(1985IA01, 1986FE1A, 1989DO1K). Antiproton reactions:(1985BA51). Hypernuclei:(1984BO1H, 1985IA01, 1986AN1R, 1986DA1G, 1986DA1B, 1986FE1A, 1986GA1H, 1986KO1A, 1986YA1F, 1987MA2A, 1987MI38, 1987PO1H, 1987WU05, 1988MO1L, 1989BA92, 1989BA93, 1989DO1K, 1989KO1H, 1989MI30, 1989TA17). Other topics:(1985AN28, 1985PH01, 1985SH24, 1986AN07, 1986WI03, 1987CH02, 1988KW02, 1989OR02, 1989PO1K, 1990MU10). Groundstate properties of ^{15}N:(1985AN28, 1985AR11, 1985BL20, 1985GO1A, 1986BA04, 1986BA49, 1986MC13, 1986WI03, 1986WUZX, 1987DE03, 1987FU06, 1987IC02, 1987KI1C, 1987MI27, 1988AR1B, 1988AR1I, 1988CH1T, 1988DE09, 1988FU04, 1988KE1B, 1988NI05, 1988SH07, 1988VA03, 1988WA08, 1988WO04, 1989CH24, 1989FU05, 1989GOZQ, 1989NE02, 1990SA10, 1989WO1E, 1990VA1G, 1990VA01).
μ = 0.283188842 (45) nm (see (1989RA17)) Natural abundance:(0.366 ± 0.009)% (1984DE53). ^{15}N*(5.27):μ = +(2.35 ± 0.18) nm (see (1989RA17)).
Thick target neutron yields are reported at E(^{6}Li) = 40 MeV (1987SC11). The yield of p_{0} and p_{1} (reaction (b)) for E(^{6}Li) = 3.84 to 6.40 MeV shows some broad structure: analysis in terms of Ericson fluctuation theory gives a value of ≈ 0.4 MeV for the average level width at E_{x} = 28 MeV in ^{15}N. The excitation functions for t_{0} (reaction (c)), α_{0}, α_{1} and α_{2} (reaction (d)) show broad structures for E(^{6}Li) = 4 to 14 MeV. See (1976AJ04) for the references.
See (1985MC1C; applied).
See (1988GO1H; E(^{12}C) = 65 MeV; prelim.).
At E(^{6}Li) = 4.9 MeV, thirty proton groups are observed corresponding to ^{15}N states with E_{x} < 16.8 MeV. Angular distributions have been measured for the proton groups corresponding to ^{15}N*(5.27 + 5.30, 6.32, 7.16 + 7.30, 7.57, 8.31, 8.57, 9.05 + 9.15): see (1976AJ04).
At E(^{7}Li) = 24 MeV angular distributions have been studied to many of the ^{15}N states with E_{x} < 15.5 MeV: see (1981AJ01).
The 90° differential cross section for γ_{0} production has been measured for E_{α} = 5.74 to 18.0 MeV: see (1981AJ01, 1986AJ01). For the observed resonances see 15.6 (in PDF or PS). See also (1988WAZY; prelim.).
Reported resonances are displayed in 15.7 (in PDF or PS). Nine resonances have been observed in the total cross section for reaction (a) in the range E_{α} = 0.55 to 2.40 MeV (1988WAZY; prelim.) [astrophysical reaction rates will be derived]. For thick target neutron yields for E_{α} = 1.0 to 9.8 MeV, see the review in (1989HE04). See also (1987EL1B; applied). The total cross section for reaction (b) has been measured for E_{α} = 0.9 to 1.7 MeV: resonance information is deduced by (1987TU01). At higher energies (to 25 MeV) the p_{0} excitation functions show broad features: see (1981AJ01).
The yield of d_{0} has been measured for E_{α} = 13.5 to 25 MeV. The excitation functions for t_{0} and t_{1} (to 25 MeV) show strong uncorrelated structures: see (1976AJ04, 1981AJ01). See also (1989VA07).
Observed resonances are shown in 15.7 (in PDF or PS).
At E(^{6}Li) = 34 MeV angular distributions are reported to the states with 5.3 < E_{x} < 16.3 MeV: this reaction appears to be less selective than reaction 11. The most strongly populated states are ^{15}N*(9.2, 10.5, 10.7, 13.1, 14.8, 15.5). See (1981AJ01). See also (1990AZZZ).
At E(^{7}Li) = 24 and 34 MeV, angular distributions to states with 5.3 < E_{x} < 15.6 MeV have been measured: ^{15}N*(9.8, 10.5, 10.7, 15.4, 15.5) are particularly strongly populated at 34 MeV. J^{π} = 9/2^{+}, 9/2, 11/2, 9/2, 11/2, 13/2, 15/2 are suggested for ^{15}N*(10.69, 12.56, 13.03, 13.19, 13.84, 14.11, 15.37). Only ^{15}N*(15.52) appears to have a large cluster component corresponding to ^{11}B + α. See (1981AJ01). For a study of the γdecay, see (1981AJ01). At E(^{7}Li) = 34, 40, 45 and 55 MeV states at E_{x} = 13.88, 17.10, 18.67, 18.81, 19.70, 19.93 and 22.86 MeV are reported to be strongly populated (1990AZZZ; prelim.). See also (1990DA03).
Gammaray cross sections involving ^{15}N*(5.3, 6.32, 7.16, 7.30, 7.57, 8.57) are reported at E_{c.m.} = 1.92, 2.30 and 2.46 MeV (1986CU02). See (1984DA17) for cross sections and Sfactors.
Angular distributions have been measured at E(^{16}O) = 27 to 60 MeV involving the two protonhole states of ^{15}N[^{15}N*(0, 6.32); J^{π} = 1/2^{}, 3/2^{}] and ^{12}C*(0, 4.4, 9.6): see (1976AJ04). See also (1989KA1N; theor.).
The 90° excitation function for γ_{0} in the range 1.0 to 6.5 MeV [see (1981AJ01, 1986AJ01)] shows one very strong resonance (at peak, 4.4 ± 0.5 μb/sr) corresponding to ^{15}N*(16.7) as well as two other strong (unresolved and/or broad) resonances at E_{t} ≈ 3.3 and 6 MeV: 15.8 (in PDF or PS) shows the derived parameters. 15.8 (in PDF or PS) also displays the structures observed in reactions (b) → (e). At E_{pol. t} = 17 MeV the polarization and analyzing power for the transition to ^{14}C_{g.s.} (reaction (c)) are shown to be the same, as required by the conservation of parity. The VAP for the elastic scattering (reaction (d)) has been measured at E_{t} = 9 and 11 MeV: see (1985AJ01). See (1981AJ01) for the earlier work. See also (1985SA31, 1990HA46; theor.).
Individual states have not been resolved in this reaction. The cross section over the bound states of ^{15}N is < 0.03 nb at E_{π+} = 5 MeV and 0.8 ± 0.2 nb at E_{π+} ≈ 60 MeV [E(^{3}He) = 170.2 and 236.3 MeV, respectively] (1988HO15). For the earlier work see (1984BI08, 1986SC23).
Angular distributions have been measured at many energies for E_{α} = 13.4 to 96.8 MeV: see (1976AJ04, 1981AJ01, 1986AJ01). See also (1987MIZY, 1988BRZY; E_{α} = 48 MeV; prelim.), (1987BI1C; E_{α} = 218 MeV; prelim.) and (1989BR1J).
Observed ^{3}He groups are displayed in 15.9 (in PDF or PS) of (1981AJ01). Comparisons of the angular distributions obtained in this reaction at E(^{6}Li) = 60.1 MeV and in the (^{6}Li, t) reaction shows analog correspondence for the following pairs of levels: 5.27  5.24, 7.16  6.86, 7.57  7.28, 8.57  8.28, 10.80  10.48, 13.15(u)  12.84, 15.49(u)  15.05 [first listed is E_{x} in ^{15}Nsecond in ^{15}O]. [E_{x} are nominal; u = unresolved.] For γdecay measurements see 15.5 (in PDF or PS). See also (1990AZZZ).
Observed αgroups are shown in 15.9 (in PDF or PS). Angular distributions have been measured to E(^{7}Li) = 48 MeV. Comparison of spectra from this reaction (E(^{7}Li) = 34.9 MeV) with those from ^{13}C(^{6}Li, α) (reaction 26) lead to configurations of (d)^{3} for ^{15}N*(10.7, 12.57, 13.20, 15.42) and suggest that ^{15}N*(12.57, 13.20) have lower J than ^{15}N*(10.7, 15.5), probably J ≤ 7/2. ^{15}N*(13.02) is shown to be p(d)^{2} in aggreement with J^{π} = 11/2^{}: see (1981AJ01). ^{15}N*(9.155) [J = 5/2] decays to ^{15}N*(5.30) [J = 1/2^{+}] by an E2 transition; therefore its parity is positive. It has a large triton cluster parentage. This is not true of ^{15}N*(9.152): see (1981AJ01). For γdecay measurements see 15.5 (in PDF or PS). See also (1985SA31; theor.).
For reaction (a) see (1981AJ01) and (1988MA07). For reaction (b) see (1989VO1D). For reaction (c) see (1984RA07).
The 90°  95° yields of γ_{0} have been measured for E_{d} = 1 to 10 MeV: observed resonances are displayed in 15.10 (in PDF or PS). The γray angular distributions are consistent with the emission of predominantly E1 radiation except for evidence of M1/E2 transitions in the region E_{x} = 20  21.5 MeV: see (1981AJ01). See also (1990HA46).
Observed resonsnces are displayed in 15.10 (in PDF or PS). Polarization measurements have been carried out at E_{pol. d} = 12.3 MeV (reaction (a)) and 13 and 56 MeV (reaction (b)): see (1986AJ01). See also (1987AB04). For VAP measurements (reaction (c)) at E_{pol. d} = 70 MeV to ^{13}B_{g.s.} see (1986MO27).
Excitation functions for elastically scattered deuterons have been measured in the range E_{d} = 0.4 to 5.7 MeV: see (1976AJ04). Polarization studies have been reported for E_{d} = 12.5 to 15 MeV and at E_{pol. d} = 56 MeV: see (1981AJ01, 1986AJ01).
Observed resonances are listed in 15.10 (in PDF or PS). For polarization measurements to E_{pol. d} = 29 MeV [reactions (a), (b)] see (1981AJ01).
Observed proton groups and γrays are listed in 15.11 (in PDF or PS) of (1981AJ01). Angular distributions have been reported for E(^{3}He) = 4.37 to 20 MeV: see (1981AJ01).
At E_{α} = 34.9 MeV a ZRDWBA analysis has been made of the angular distributions to ^{15}N*(5.27, 5.30, 7.16, 7.30, 7.56, 8.31, 8.57, 9.05, 9.15, 10.07, 10.53, 10.69, 11.43, 11.94, 12.10, 12.33, 12.49, 12.56, 13.00, 13.83, 14.08). L = 0 for the group(s) to ^{15}N*(9.15, 10.69); L = 2 for ^{15}N*(12.56); L = 3 for ^{15}N*(5.27, 7.16, 7.56); L = 4 for ^{15}N*(11.94, 13.00); L = 1 for the remaining transitions (1984YA03). See also 15.11 (in PDF or PS) of (1976AJ04).
Angular distributions have been measured at E(^{6}Li) = 32 MeV to ^{15}N*(0, 5.30, 6.32, 7.16, 7.30, 7.57, 8.31, 8.57, 9.15, 9.23, 9.83, 10.07, 10.70, 11.94, 13.00): the results are consistent with the previously known J^{π}, with (odd) parity for ^{15}N*(9.83) and with J^{π} = 9/2^{} for ^{15}N*(11.94): see (1981AJ01).
For reaction (a) see (1988MA07). For reaction (b) see (1981AJ01).
Observed resonances are displayed in 15.11 (in PDF or PS); the branching ratios are shown in 15.5 (in PDF or PS). Narrow anamolies (in the γ_{0} yield for E_{p} = 2.8 to 30 MeV) are reported at E_{p} = 10.0, 11.0, 12.35, 13.6, 16.4 MeV. A good fit to the total cross section (E_{pol. p} = 7.5 to 19 MeV) is obtained with the GDR split into peaks at E_{x} = 21.0 and 25.5 MeV with Γ = 6 and 2 MeV, respectively. The integrated E2 cross section for E_{x} = 19.5 to 27.0 MeV is (6.8 ± 1.4)% of the isoscalar sum rule. The reaction thus shows no sign of a collective E2 resonance in that E_{x} region. [Another study shows no appreciable E2 strength concentration for E_{x} = 14.3 to 23.3 MeV.] Above the GDR region the 90° γ_{0} cross section decreases smoothly with energy except for a small peak which would correspond to ^{15}N*(37.0). See (1981AJ01, 1986AJ01) for the references. See also (1985CA41, 1988CA26, 1990GO25; astrophysics) and (1990HA46; theor.).
Observed resonances are displayed in 15.11 (in PDF or PS). Cross sections have recently been measured for E_{p} = 0.67 to 1.20 MeV (1989KEZZ; prelim.). Polarization measurements are reported at E_{pol. p} = 160 MeV (1984TA07, 1987RA15; A_{y}; D_{NN}(0°); n to ^{14}N*(0, 2.31, 3.95, 13.72)). Forwardangle differential cross sections have been measured at E_{p} = 200, 300, (400), 450 MeV (1986AL18, 1989AL04; n_{1} + n_{2}) and at 492 MeV (1989RA09; n_{1}, n_{2}). See (1986AJ01) for the earlier work. See also (1985TA23), (1986TA1E, 1987TA22, 1989SU1J), (1985CA41, 1988CA26; astrophysics) and (1987BE1D, 1987LO1D; theor.).
Observed resonances and anomalies are displayed in 15.11 (in PDF or PS). For polarization measurements see (1981AJ01, 1986AJ01). See also (1989AM01; theor.).
Angular distributions have been measured for E_{d} = 1.3 to 6.5 MeV: see (1976AJ04).
Angular distributions have been studied at E(^{3}He) = 23 MeV to ^{15}N*(0, 5.27 + 5.30, 6.32, 7.16, 7.30): see (1981AJ01). See also (1976AJ04).
See (1988AL1G); E(^{7}Li) = 27 MeV; prelim.).
The thermal cross section is 79.8 ± 1.4 mb (1990IS05). See also (1988MCZT). Observed γrays from thermal neutron capture are displayed in 15.12 (in PDF or PS). See also 15.5 (in PDF or PS). The 90° γ_{0} yield and angular distributions have been measured for E_{n} = 5.6 to 15.3 MeV. The cross section shows two prominent dips at E_{x} = 16.7 and 18.1 MeV [compare with ^{14}N(p, γ); reaction 9 in ^{15}O] and broad structures at E_{x} ≈ 17 and 19 MeV. The angular distribution data are consistent with essentially pure E1 radiation in the region E_{x} = 17 to 24 MeV (1982WE01). See also (1989WO1C) and (1989GU1J; astrophys.).
The scattering amplitude (bound) a = 9.37 ± 0.03 fm, σ_{free} = 10.05 ± 0.12 b, σ^{spin}_{inc} (bound nucleus) = 0.49 ± 0.11 b (1979KO26). Observed resonances are displayed in 15.13 (in PDF or PS): for a discussion of the evidence leading to J^{π} assignments see (1959AJ76). Cross section curves and a listing of references can be found in (1988MCZT). Recent measurements are reported at E_{n} = 0.14, 1.3 and 2.1 MeV (1988KO18; σ_{t}), 7.67 to 13.50 MeV (1986CH2F; el and inel; prelim.). 10.96, 13.96 and 16.95 MeV (1985TE01; elastic). The (n, n'γ) cross section has been measured for E_{n} = 2.5 to 3.5 MeV (1989STZW; prelim.; applied). Analyzing powers for the n_{0} group have been measured for E_{pol. n} = 10 to 17 MeV (1989LI26). See also ^{14}N, (1988BA55, 1986LI1M) and (1988MA1H).
Cross sections have been measured for E_{n} = 10 to 37 MeV [see (1988MCZT)] and at E_{n} = 13.40 to 14.87 MeV (1989KA1S). See also (1989KA2B).
(1989KO11), using the "white" neutron source LANSCE, have measured the (n, p) cross section from 61 meV to 34.6 keV. Their results support the role of this reaction as a "poison" during sprocess nucleosynthesis. [See (1989KO11) for a discussion of other measurements.] See also (1988BR17, 1989KEZZ). For a display of the measured cross sections for (a) and (c), see (1988MCZT). See also (1988SUZY; E_{n} = 5.0 to 10.6 MeV; σ = 11 to 30 mb; prelim.) for reaction (c) and (1988MA1H). For resonances in reactions (a) and (e), see 15.13 (in PDF or PS). (1986SU15) report doubledifferential cross sections at E_{n} = 27.4, 39.7 and 60.7 MeV for all five reactions. See also (1989CH2E).
At E_{pol. p} = 200 MeV, angular distributions and A_{y} have been measured for the transitions to ^{15}N*(0, 6.32, 8.31) as well as for a number of unresolved transitions. A sharp group at E_{x} = 21.5 MeV is suggested to correspond to a 15/2^{} state (1988AZ1D, 1987AZZZ; Ph.D. thesis and abstract).
Proton groups (and γrays) from this reaction are displayed in 15.15 (in PDF or PS) of (1981AJ01). The results include E_{x} = 7567.1 ± 1.0 keV for ^{15}N*(7.57). Newer values, derived from measurements of proton groups in a spectrograph, are 5270.2 ± 1.3, 6324.0 ± 1.0, 7154.85 ± 0.17, 7300.80 ± 0.09, 7563.25 ± 0.19, 8312.79 ± 0.12, 8571.53 ± 0.25, 9050.24 ± 0.33, 10064.34 ± 0.31 and 11235.5 ± 0.5 keV (1990PI05). Angular distributions have been meausred for E_{d} = 0.32 to 52 MeV and lead to l_{n}, J^{π} and spectroscopic factors: see 15.15 (in PDF or PS) in (1981AJ01). Branching ratios and multipolarities are shown in 15.15 (in PDF or PS). See also (1985LI1H, 1985ME1E, 1987SI1D, 1988LI1E, 1988VI1A, 1989VI1E; appliactions).
See (1981AJ01) and (1988DA12; theor.).
See reaction 1 in ^{15}C and 15.14 (in PDF or PS).
The total photoneutron cross section from threshold to 38 MeV shows a very broad GDR which extends from ≈ 16 to 30 MeV. Maxima are observed at E_{γ} ≈ 23.5 and 25.5 MeV (σ ≈ 11 mb): see (1988DI02) [based on (1982JU03; monoenergetic photons)]. However, (1989BA25) report a sharper single peak at E_{γ} = 25.5 MeV in the (γ, Sn) reaction with a cross section of ≈ 16 mb. See (1989BA25) for a discussion of the T_{<} and T_{>} components of the GDR. The (γ, n_{0}) cross section for E_{x} = 13 to 24 MeV shows a broad structure centered at E_{x} ≈ 14.5 MeV and a resonance at E_{x} = 17.3 ± 0.1 MeV. A large fraction of the photoabsorption strength leading to ^{14}N_{g.s.} is due to the formation of 3/2^{+}, T = 1/2 states in ^{15}N which decay by dwave emission. The absorption is essentially pure E1 (1983WA03). See also (1981AJ01). The (γ, 2n) reaction has been studied from threshold to 38 MeV [see (1988DI02)] and more recently from 20 to 28 MeV by (1988MC01). The cross section remains near zero for 3 MeV above threshold and then rises sharply at about 24 MeV to a maximum value of 1.7 mb (1988MC01) [see, however, (1982JU03)]. For discussions of the results in terms of the density of T_{>} states in ^{14}N, see (1988MC01, 1989BA25 (p.511)). For discussions of the (γ, p) reaction see (1981AJ01) and (1989BA25). The latter show a curve for the total absorption cross section [(γ, n) + (γ, p)] from 10 and 27 MeV dominated by a peak (see above) at E_{γ} ≈ 25 MeV with σ ≈ 23 mb. A study at E_{e} = 18.8, 20.8, 25.7 and 29.7 MeV (reaction (d)) shows a "pigmy" resonance at E_{x} = 14.8 MeV, a shoulder at 15.6 MeV, a peak at 16.7 MeV [probably 1/2^{+} but 3/2^{+} is not ruled out], and the giant dipole resonance, which exhibits a great deal of structure, centered at 22 MeV. The data on the pigmy resonance are consistent with an admixture of ≈ 1% 3/2^{} (E2) or 1/2^{} (M1) to a predominantly 1/2^{+} (E1) state. The experiment shows that for 14 < E_{x} < 28 MeV the reaction goes predominantly via 1/2^{+} or 3/2^{+} (E1) states in ^{15}N; the T = 3/2 strength is concentrated above 18 MeV: see (1981AJ01). The cross section for for d_{0} [reaction (e)] is reported at 90° for E_{γ} ≈ 20.5 to 28.5 MeV: a resonance is observed at E_{x} ≈ 21.9 MeV. The (γ, t_{0}) cross section (reaction (f)) at 90° decreases from a value of 30 μb/sr at 20 MeV to 5 μb/sr at 22 MeV and remains flat out to 25 MeV. Comparison of this cross section, and those of the other photonuclear reactions, suggest an isospin splitting of ≈ 6 MeV with the T = 1/2 strength concentrated between 16 and 21 MeV and the T = 3/2 strength between 21 and 28 MeV. ^{15}N*(21.9) is not observed. See (1981AJ01) for references. For reaction (g) [to ^{15}O_{g.s.}] see (1988LI23, 1989KO28). See also (1985GO1A, 1987KI1C; theor.).
See 15.15 (in PDF or PS) and (1981AJ01). See also (1987MO03).
The charge r.m.s. radius of ^{15}N is 2.612 ± 0.009 fm. The C0 elastic scattering form factor of ^{15}N has been measured over q = 0.4  3.2 fm^{1} (1988DE09). Inelastic groups are displayed in 15.15 (in PDF or PS). The giant resonance is split into two main peaks at E_{x} = 22 and 25.5 MeV with some structure around 20 MeV. Γ_{γ0}(C1) = (1.1 ± 0.3) × 10^{3} eV (14  18.5 MeV), Γ_{γ0}(C2) = 12.5 ± 2.0 eV assuming the states responsible are 3/2^{+} and 3/2^{}, respectively. For E_{x} = 18.5 to 30 MeV, Γ_{γ0}(C1) = (1.96 ± 0.04) × 10^{4} eV while Γ_{γ0} < 0.1 eV for any C2 strength. See (1981AJ01, 1986AJ01) for references. See also (1988MUZV; (e, e'γ); prelim) (1986PA1C, 1987DE43, 1988LI23, 1988PA1S, 1989KO28, 1990PA1H) and (1986JE1B, 1987DO12, 1988FU04, 1988GOZM, 1988SH07, 1989FU05, 1989WO1E, 1990BL09, 1990FU04; theor.).
At E_{π±} = 164 MeV angular distributions have been studied to states at E_{x} = 10.68 ± 0.03, 12.52 ± 0.02, 14.04 ± 0.03 and 17.19 ± 0.03 MeV: J^{π} = 9/2^{+}, 9/2^{+}, (9/2^{+}, 7/2^{+}) and (9/2^{+}, 7/2^{+}), respectively, as well as to the ^{15}N_{g.s.}. Additional π^{+} cross sections were measured at 120 and 260 MeV: peaks were observed at E_{x} = 20.11 ± 0.06 and 23.19 ± 0.06 MeV [both are probably T = 3/2 states]. ^{15}N*(5.27, 6.32, 7.57) were also populated (1985SE06). At E_{π+} = 164 MeV, elastic scattering has been studied from ^{15}pol. N: A_{y} for θ = 60°  100° is consistent with zero (1989TA21, 1990TA1L). See also (1990TAZS) and (1988GOZM; theor.).
See ^{16}N in (1986AJ04). See also (1989FU1J).
Angular distributions of elastically scattered protons have been measured at E_{p} to 44.2 MeV: see (1981AJ01, 1986AJ01). For measurements of K^{y'}_{y} at E_{pol. p} = 65 MeV see (1990NA15). See also ^{16}O in (1986AJ04) and (1990DU01; theor.).
Angular distributions of elastically scattered deuterons have been measured at E_{d} = 5  6 MeV. Elastic and inelastic ^{3}He distributions have been studied for E(^{3}He) = 11 to 39.8 MeV: see (1976AJ04). Elastic distributions and A_{y} have also been measured at E(pol. ^{3}He) = 33 MeV (1986DR03).
At E_{α} = 40.5 MeV, a number of particle groups have been observed and angular distributions have been measured: see 15.17 (in PDF or PS) of (1976AJ04). At E_{α} = 48.7 and 54.1 MeV elastic angular distributions have been reported by (1987AB03). See also (1981AJ01) for additional information and (1985SH1D; theor.).
The elastic scattering has been studied at E(^{7}Li) = 28.8 MeV: see (1986AJ01).
Angular distributions of elastic scattering have been measured at E(^{15}N) = 31.5 to 47 MeV [reaction (a)] and E(^{13}C) = 105 MeV [reaction (b)]: see (1981AJ01, 1986AJ01) [also for yield measurements]. See also (1986HA1F, 1989BEZC) and (1985HU04, 1986BA69, 1986HA13; theor.).
Elastic angular distributions have been measured at E(^{16}O) = 35.1 and 42.6 MeV: see (1986AJ01). For fusion cross sections and yields see (1976AJ04, 1986AJ01) and (1985NO1C, 1986HA1F). See also (1985HU04; theor.).
Elastic distributions have been measured in the range E(^{15}N) = 32.8 to 69.8 MeV [reaction (a)] and at 44 MeV [reaction (b)]: see (1981AJ01, 1986AJ01). See also (1988SN1A).
See ^{15}O.
Over the giant resonance region in ^{16}O, the decay takes place to the oddparity states ^{15}N*(0, 6.32) and less strongly to the evenparity states ^{15}N*(5.27, 5.30, 8.31, 9.05) and to ^{15}N*(9.22): see (1970AJ04, 1976AJ04). At E_{e} = 500 MeV most of the 1p hole strength is concentrated in the groups to ^{15}N*(0, 6.32). The 1s state shows up as a very wide asymmetric structure centered at E_{x} ≈ 41 MeV: see (1981AJ01). See also (1990LE1P). In the range E_{γ} = 101.5 to 382 MeV differential cross sections are reported for the p_{0}, (p_{1+2}) and p_{3} groups at θ = 45°, 90° and 135° (1985LE07). Differential cross sections have also been measured at E_{γ} = 196, 257, 312, 316 MeV for the p_{0} and p_{1} → 3 groups [the latter not at 316 MeV] (1988AD07, 1985TU02). ^{15}N*(0, 6.3, 10.8) have been populated at E_{e} = 500 MeV (1982BE02). See also (1986AJ01), (1987VOZR, 1988LEZW, 1989LEZY; prelim.), (1987MA1K) and (1985CA17, 1985GO1B, 1986CH05, 1986LU1A, 1986PO14, 1987RY03, 1988CA10, 1988DUZX, 1988HO10, 1988YA08, 1988LO07, 1988MC03, 1988RY03, 1989RY01, 1990BRZY, 1990FL1A, 1990OWZZ; theor.).
Gamma rays from the decay of one of the states at 5.3 MeV and from ^{15}N*(6.3) are reported by (1983VA1E).
Angular distributions of the d_{0} group have been reported at E_{n} = 14 and 14.4 MeV: see (1976AJ04). See also (1988YOZX; E_{n} = 60 MeV; prelim.) and (1990MC04; applied).
At E_{π±} = 240 MeV, the spectra are dominated by ^{15}N*(0, ≈ 6.5). The π^{+}/π^{} ratio has been measured for the groundstate transitions (1984KY01). At E_{π+} = 2.0 GeV/c differential cross sections have been determined for the transition to ^{15}N*(6.3) (1983KI01). At E_{p} = 505 MeV the summed proton spectrum shows two peaks corresponding to the knockout of p_{1/2} and p_{3/2} protons with binding energies of 12.12 and 18.44 MeV [^{15}N*(0, 6.32)]. Differential cross sections and (p, 2p)/(p, pn) ratios are also reported (1986MC10). For work at 1 GeV involving the knockout of s_{1/2} protons see (1985BE30). For γray production (^{15}N*(5.27)) at E_{p} = 30  40 MeV see (1988LE08). See also (1985KI1A, 1986CH1J, 1987VD1A), (1987LA11, 1988LE08; astrophys.) and (1986BO1A; theor.). For earlier work see (1976AJ04).
Angular distributions of ^{3}He groups have been measured for E_{d} = 20 to 82 MeV: see (1976AJ04, 1981AJ01). The spectra are dominated by the transitions to ^{15}N*(0, 6.32). A ZRDWBA analysis leads to C^{2}S = 2.25 and 3.25 for these two states [and to 2.37 and 3.31 for the analog states in ^{15}O studied with the (d, t) reaction]. J^{π} = 3/2^{} for both ^{15}N*(9.93, 10.70): see (1981AJ01). See also (1987MO03) for a reanalysis of C^{2}S.
At E_{α} = 139.2 MeV the absolute spectroscopic factors S = 5.4 and 6.9 for ^{15}N*(0, 6.32) (1987SA01).
For reaction (a) see (1986GL1E). For reaction (b) see (1988MA07) and for (c) see (1988AU03). For other heavyion reactions see (1981AJ01, 1986AJ01).
At E_{p} = 39.8 MeV angular distributions of the groups to ^{15}N*(0, 6.32) have been compared with those to the analog states in ^{15}O reached in the (p, t) reaction: see (1976AJ04).
Angular distributions of α_{0} have been measured for E_{p} = 0.125 to 42.2 MeV: see (1976AJ04, 1981AJ01) and ^{19}F in (1987AJ02). At E_{p} = 40.9 MeV angular distributions have also been studied to ^{15}N*(0, 5.27 + 5.30, 6.32, 7.57, 9.15[u], 9.83[u], 10.7[u], 11.24[u], 11.44, 12.52[u] (1987CA15; see for C^{2}S). For ^{15}N*(5.27), τ_{m} = 2.49 ± 0.24 ps, g = 0.94 ± 0.07 (1983BI10). See also (1986CO1F, 1988FI1C, 1989NW1A, 1990MI15; applied) and (1986BA89, 1988CA26; astrophys.).
Angular distributions involving ^{15}N*(0, 5.3, 6.3) have been measured in the range E_{d} = 9.0 to 28 MeV [see (1976AJ04, 1981AJ01)].
See (1976AJ04) and (1986HA1E; theor.).
