(See Energy Level Diagrams for 13C)
Shell model: (1970CO1H, 1970HS02, 1970TA1J, 1971AR1R, 1971GR02, 1971NO02, 1972DE1H, 1972EL1C, 1972GU05, 1972LE1L, 1973DE13, 1973HA49, 1973KU03, 1973MA1X, 1973MA1K, 1973MU18, 1973SA30, 1974PH1D, 1975ME24, 1975MI12).
Collective and deformed models: (1971AR1R).
Electromagnetic transitions: (1971DI1G, 1971GR02, 1971JA13, 1972GU05, 1972NA05, 1973HA49, 1973HA1Q, 1973SA25, 1973SA30, 1974AD1B, 1974CH46, 1974HA1C, 1974MU13, 1974RO1R, 1974RO1T, 1975FO1L, 1975KU21, 1975ME24).
Astrophsyical questions: (1972CL1A, 1972UL1A, 1973AR1E, 1973AU1B, 1973AU1D, 1973AU1C, 1973BO1R, 1973CO1B, 1973DA1L, 1973SA1J, 1973SC1T, 1973SM1A, 1973TA1D, 1973TR1B, 1973UL1B, 1974BE1R, 1974BO2K, 1974DA1N, 1974LA1J, 1974LA1K, 1974SC1F, 1974TO1C, 1975AR1E, 1975AU1D, 1975BR1J, 1975DE1F, 1975DE1H, 1975EN1A, 1975KI1D, 1975NO1D, 1975SC1H, 1975SN1A, 1975TO1B, 1975TR1A).
Pion capture and reactions (See also reaction 37.): (1970BJ1A, 1970DO04, 1970WE1D, 1971DA10, 1971IN1A, 1971KA62, 1973AL1D, 1973AU06, 1973DI08, 1973EI01, 1973MI1H, 1973NA1H, 1973NA14, 1973RO10, 1974HO13, 1974KA07, 1974LE25, 1974LI15, 1974MI06, 1974MI11, 1974RE1E, 1974UL02, 1975AL1K, 1975EI1D, 1975GI1B, 1975HU1D, 1975KA1R, 1975KI1E, 1975RE01, 1975TO01, 1976GI01, 1976SH01).
Other topics: (1969WA1C, 1970CO1H, 1970PE18, 1970SH1C, 1970SU1B, 1971AR03, 1971AU1G, 1971BA2Y, 1971GR16, 1971JA13, 1971SE1C, 1971NG01, 1972AN05, 1972CA37, 1972CH16, 1972HA57, 1972LE1L, 1973DE13, 1973GO1H, 1973JU2A, 1973KO1J, 1973KU03, 1973MA48, 1973RA1E, 1973SA25, 1973WI15, 1974CA1H, 1974MU13, 1974SI04, 1974ZU1A, 1975GR03, 1975KU01, 1975MO1M, 1976MA04, 1976PA03).
Ground state: (1969LE1B, 1971TA1A, 1972GL06, 1972GU05, 1972LE1L, 1972LE1N, 1972VA36, 1973MA1K, 1973SA25, 1973SA30, 1973SU1C, 1974DE1E, 1974HA27, 1974MU13, 1974NE1B, 1975AL19, 1975BE31, 1975ME24, 1976PA03).
Mass of 13C:
μ = +0.702381 ± 0.000002 nm (1964LI14);
μ = 0.7020 ± 0.0004 nm (1973CO1P).
See also Table 13.5 (in PDF or PS): Lifetimes of low-lying states of 13C, and Table 13.6 (in PDF or PS): Summary of results on the total radiation widths of the low-lying levels of 13C - 13N.
The yield curves for d0 (E(6Li) = 4 to 14 MeV), t0 (E(7Li) = 5 to 14 MeV) and α0 (E(6Li) = 4 to 14 MeV) show broad, uncorrelated structures. Energy-averaged differential cross sections are also reported for a number of 12B, 11B and 10B states (1971WY01). Total cross section measurements have been measured for E(7Li) = 3.8 to 6.0 MeV for p0 → p2, p3+4, p5; d0 → d3, d4+5, d6; t0 → t2; and α0: the total cross sections generally increase smoothly with energy without showing any structure (1967KI03). The 11C yield has been measured for E(6Li) = 1.2 to 3.6 MeV by (1961NO05). See also 9Be and 10B in (1974AJ01), 11B and 12B in (1975AJ02), (1969KA1E) and (1972GA1E).
Earlier reports of the excitation of the first T = 3/2 state in this reaction have not been published: see (1970AJ04).
Resonances for n0 and n1, for γ-rays from 12C*(4.4, 12.7, 15.1) and resonances in the total neutron cross section are given in Table 13.8 (in PDF or PS). The yield of neutrons to 12C*(7.66, 9.64) has been measured for Eα = 2.9 to 6.4 MeV and 5.9 to 6.4 MeV, respectively (1972OB01). The n0 and n1 yields for Eα = 1.5 to 7.5 MeV and the n2 yield for Eα = 3.8 to 7.5 MeV are reported by (1970VA23).
Polarization measurements have been reported at En = 1.75 and 1.96 MeV (1969KL09; n0), 2.55 MeV (1970ST15, 1970ST16; n0), 2.6 MeV (1971KL04; n0), 4.5 to 5.85 MeV (1973DE14†; n0, n1) and 22.9 MeV (1973OK06; n0, n1). For earlier measurements see (1970AJ04). See also (1970TA06). For astrophysical implications see (1968DA1D, 1972OB01, 1975FO19). See also (1971AN1L, 1975KA26), (1971WA1D) and (1971EL1B; applied). Reaction (b) has been studied at a number of energies in the range Eα = 17 to 44 MeV (1970KR09).
† The n0 cross section and polarization are described for En = 4 to 6 MeV in terms of five broad states: see Table 13.8 (in PDF or PS).
Excitation curves have been measured for Eα = 26.5 to 27.5 MeV for the d0 → d3, d4+5 and d6 groups: no structure is observed (1975PU01). See also 11B in (1975AJ02). At Eα = 26.0 to 27.5 MeV yield curves have been obtained for the t0, t1 and t3 groups: the t2 group to 10B*(1.74) is not populated at θ = 25° and 45°; the yield curves do not display structure (1974KE06).
A number of excitation functions have been measured for elastically scattered alpha particles (reaction (a)) for Eα = 1.4 to 20 MeV: these show considerable resonance structure with the variations being most prominent below 10 MeV but persisting up to 20 MeV (1965TA04, 1970GO1G, 1973GO15, 1974SA16). The parameters resulting from a best-fit of the excitation functions are displayed in Table 13.9 (in PDF or PS): see footnotes to that table for a summary of the most important caveats (1973GO15). For reactions (a) and (b) see 9Be in (1974AJ01). For reaction (b) see (1973WE03). For a spallation study see (1974RA11).
At E(6Li) = 23.8 MeV angular distributions are reported to 13C*(0, 3.1, 3.6, 6.9, 7.5, 9.9, 10.8, 12.0, 13.3). There is some indication of the population of 13C*(9.5, 13.9, 14.5, 15.2, 16.7, 18.5) (1971GO24). See also (1970OG1A, 1973OG1A).
At E(7Li) = 5.6 to 6.2 MeV, angular distributions are reported for t0, t1, t2+3, t4 (1969SN02). The t0 angular distribution has been measured for E(7Li) = 1.7 to 1.9 MeV (1969KA1C). Many of the states populated in reaction 9 are also strongly populated in this reaction (1971GO24: E(7Li) = 30.3 MeV). See also (1970OG1A, 1972GA1E).
Angular distributions have been measured at E(12C) = 12 and 15 MeV involving the transitions to 13C*(0, 3.09, 3.85): the extracted neutron spectroscopic factors for these three states are 0.80, 1.02 and 0.89, respectively (1970BA49, 1971BA68).
The p0 and p1 yields from reaction (a), the d0 yield from reaction (b) and the α0 yield from reaction (c) have been determined for Et = 0.8 to 2.0 MeV. There is no evidence of resonance behavior (1963HO19).
Proton groups have been observed to the first four states of 13C: see (1959AJ76) and (1975WI04). Angular distributions of ground state protons have been measured at many energies up to Eα = 30.4 MeV: see (1970AJ04) and 14N.
The τm of 13C*(3.85) is 9.0+2.5-1.5 psec (1968RI16), 10.7 ± 1 psec (1969HE22), 9.9 ± 0.9 psec (1970GA01). The intensity ratio for the transitions (3.85 → 3.68)/(3.85 → 0) is 0.55 ± 0.03. The cascade decay via 13C*(3.09), relative to the g.s. decay, is (2.5 ± 0.5) × 10-2. Eγ = 3854 ± 1 keV (1969LI07). Studies of this reaction lead to Jπ = 3/2- and 5/2+ for 13C*(3.68, 3.85): see (1970AJ04) for a summary of the evidence and (1971HIZF). See also (1967SP09) and (1971BU1K; theor.).
Comparisons of the relative intensities of the 3He groups in this reaction and of the triton groups in the mirror reaction (see reaction 11 in 13N) at E(6Li) = 18 MeV suggest that the following states are analogs: 6.86 - 6.36, 7.49 - 7.16, 9.50 - 9.00, 9.90 - 9.48, (10.82 + 10.75) - (10.36 + 10.36) [the first (set of) Ex is in 13C, the second in 13N]. An angular distribution is also reported for 13C*(9.50) and the widths for 13C*(7.55, 7.68, 9.50) are determined to be < 30, 60 ± 30 and < 30 keV, respectively (1974HO06).
Angular distributions have been measured at E(7Li) = 5.20 MeV for the α0, α1, α2+3 and α4 groups (1966MC05).
The 90° γ0 excitation curve measured for Ed = 1.0 to 4.2 MeV shows a resonance at Ed = 2.0 ± 0.1 MeV (13C*(20.4)) with Γlab ≈ 0.6 MeV: the peak cross section is ≈ 1.1 μb/sr. The angular distributions of γ0 are isotropic to within 10% on and off (Ed = 3.6 MeV) resonance, consistent with E1 radiation (1973WE12).
The yield of neutrons and γ-rays has been measured for Ed = 0.2 to 11 MeV; observed resonances are displayed in Table 13.10 (in PDF or PS) (1958KA31, 1964KU09, 1965AL17, 1967DI01, 1972TH14). The yields of 4.4 and 15.1 MeV γ-rays have been measured by (1972TH14) for Ed = 2.7 to 5.0 and 4.0 to 4.8 MeV, respectively. Angular correlations for these two γ-rays are reported at Ed = 4.0, 4.5 and 4.8 MeV (1972TH14). For a listing of polarization measurements, see Table 13.11 (in PDF or PS): measurements at Ed = 11.8 MeV show that the transition to 12C*(4.4) predominantly involves j = 1/2 for the transferred proton (1971HI09). See also (1970AJ04), (1970MI1G, 1975SE07; theor.) and 12C in (1975AJ02).
Some measurements show that the thin-target yield rises smoothly from Ed = 0.3 to 3.1 MeV with no evidence of resonance: see (1970AJ04). However, (1964BR1A) and (1968CH05) report a resonance in the yields of p0, p1 and p2, and of γ1 and γ2: see Table 13.10 (in PDF or PS). Polarization measurements at Ed = 10 and 12 MeV show that pj = 1/2 for both the p0 and p1 transitions are 0.85 ± 0.15 (1970FI07, 1972FI1E, 1973FI1C). See also (1970VO09, 1974DA13, 1975HU1H) and 12B in (1975AJ02).
At low energies the excitation functions for α0 and α1 increase monotonically: see (1970AJ04). Then at Ed = 1.85 MeV a pronounced resonance is observed in the α0, α1, α2 and α3 yields (1969FR03). Some gross structure is also observed in these yields for Ed = 1.0 to 3.2 MeV (1964BR1A, 1969FR03). See also 9Be in (1974AJ01).
Levels derived from proton groups are displayed in Table 13.12 (in PDF or PS). The gamma, neutron and α-widths of the first T = 3/2 state at Ex = 15.11 MeV are displayed in Table 13.7 (in PDF or PS) where they are compared with corresponding quantities for 13N*(15.07) (1973AD02, 1975MA21). The particle decays of the T = 3/2 states show strong charge asymmetries indicating that the isovector and isotensor mixing amplitudes have similar magnitudes (1973AD02). See (1970AJ04) for the earlier work on this state.
Angular distributions have been measured at many energies, see (1970AJ04) for the earlier work and (1970ME1N, 1970ME24, 1971ME01: E(3He) = 3 MeV; Table 13.12 (in PDF or PS)) and (1973WU01, 1971WU1A: E(3He) = 4, 6, 8, 10, 12 MeV; most states below Ex = 10 MeV). For 13C*(7.49, 7.55) Γγ/Γ = 0.3 ± 0.1%, < 0.1% (1971HIZF). See also (1970MA38, 1974GU1D; theor.).
Angular distributions are reported at E(6Li) = 4.72 MeV for α0, α1, α2+3, α4 and α5+6+7 (1966MC05).
The thermal capture cross section is 3.4 ± 0.3 mb (1973MU14). Reported γ-transitions are displayed in Table 13.13 (in PDF or PS). See also (1967MO05, 1967RA24, 1975LA1K, 1975SH18), (1970CL1C, 1973CL1E; astrophys.) and (1974MA10; theor.). At En = 14 MeV, there is some indication that γ0 peaks backwards (1975AR19).
The coherent scattering length acoh = 6.6572 ± 0.0013 fm (1971KO1F, 1975KO29). (1973MU14) had adopted 6.65 ± 0.01 fm. A listing of recent σt measurements is displayed in Table 13.14 (in PDF or PS), and the recent polarization measurements are shown in Table 13.15 (in PDF or PS). See also (1972BU20, 1973FA06) and (1970GA1A) for a review of earlier angular distributions.
See also (1969BE1F, 1969FA1B, 1970AH1B, 1971CR06, 1974HE1E, 1976HO1B), (1971PL1C, 1972LA1F, 1973BR1C, 1975HA2C, 1975LA1K, 1975RO1G), (1970CO1J, 1970ER1A, 1970GN1A, 1970SH14, 1970YO1C, 1971CH01, 1971DO15, 1971GR48, 1971MI07, 1971WE08, 1972AD02, 1972FR09, 1972JO11, 1972PE11, 1972PE1H, 1972RO07, 1972RO08, 1973AD01, 1973CO27, 1973LE02, 1973MO1F, 1973WE06, 1974OL1D, 1974PH03, 1974ZA04, 1975CA05, 1976AH02; theor.), 12C in (1975AJ02) and (1970AJ04).
From threshold to En = 19 MeV, twelve resonances are observed in the yield of 4.4 MeV γ-rays: see Table 13.17 (in PDF or PS) (1959HA13, 1968BO34). Cross sections for production of 4.4 MeV γ-rays have been reported at En = 5.8 to 7.5 MeV (1970DR11) and for the n0 and n1 groups at En = 8 to 14.5 MeV (1975HA1Z, 1975HA2D). Other inelastic cross sections to individual 12C states have been measured by (1973VE03: En = 7.7, 8.2, 9.0 MeV) and by (1969GR30: En = 14.1 MeV). Earlier work is displayed in (1959AJ76, 1970AJ04). For reaction (b) see 12C in (1975AJ02) and (1969GR30, 1975AN01). See also (1969RO1F, 1973VE03, 1974ROXP, 1975HA2C, 1975LA1K), (1970CA13; theor.) and (1974CR1E; applied).
The cross section exhibits a weak resonance corresponding to Ex ≈ 20.5 MeV (1968RI02, 1972BO73) and stronger structures at Ex ≈ 21.5 MeV (1968RI02, 1970BA1L), 22.8 and 23.6 MeV (1970BA1L; abstract). See also (1971CU1B, 1972ED01, 1975LA1K, 1975MC19) and (1974OL03; theor.).
At Ep = 185 MeV, angular distributions have been observed for the π+ groups to the ground state of 13C and to Ex = 3.08 ± 0.09, 3.80 ± 0.12, 6.87 ± 0.18, 7.57 ± 0.16 and 9.51 ± 0.22 MeV. The shape of the distributions and the differential cross sections to the various states are quite different: several kinds of reaction processes appear to be involved (1973DA24). See also (1972RH1A, 1973EI1B), (1973KE02, 1974GR1Q, 1975EI1B, 1975NO05, 1976LE02; theor.) and "Pion capture and reactions" section in the "GENERAL" section here.
Measurements on the proton groups are summarized in Table 13.18 (in PDF or PS). Angular distributions have been studied at many energies: recent experiments are listed in Table 13.19 (in PDF or PS). For earlier work see (1959AJ76, 1970AJ04). Observed γ-rays are listed in Table 13.16 (in PDF or PS) of (1970AJ04): ground state decays have been observed for 13C*(3.09, 3.68, 3.85). 13C*(3.68) decays via 13C*(3.09) with a 1.6 ± 0.3% branch (1975TR07). 13C*(3.85) also decays via 13C*(3.68) with a 37 ± 4% branch (1966GO15), 36.0 ± 0.7% (1975TR07), with Eγ = 169.25 ± 0.04 keV (1969AL17) and via 13C*(3.09) with a 0.6 ± 0.2% branch (1975TR07). Mixing ratios are given in (1970AJ04). Lifetimes of the first three excited states are displayed in Table 13.5 (in PDF or PS). Recent measurements give τm = 12.4 ± 0.8 psec (1974BE48), 13.0 ± 0.4 psec (1975RA29) for 13C*(3.85): its nuclear g-factor is 0.59 ± 0.05 (1974BE48).
See also (1967SP09, 1970BO20, 1970HO37, 1973MU1H, 1975ZA06, 1976SC1G), (1974FO1J), (1969ST1D, 1970DO10, 1970EL01, 1970KU1B, 1970OH06, 1970OH1C, 1970PE1B, 1971BR1H, 1971BU02, 1971PE10, 1972DZ06, 1972GO27, 1973CO23, 1973CO27, 1973DO02, 1974GO02, 1974OR1A, 1975GR12, 1975HU01, 1975IS03; theor.) and 14N.
The angular distributions for the transitions to 13C*(0, 3.85) have been studied at E(3He) = 40 MeV (1971ST21). The proton decay of various 14N states to 13Cg.s. has been studied by (1974NO01): see 14N. See also (1970AJ04).
Angular distributions of the 3He particles have been measured at Eα = 56 MeV (1969GA11: to 13C*(0, 3.68 + 3.85)), 104 MeV (1972HA08: to 13C(0)) and 139 MeV (1973SM03: to 13C*(0, 3.85)). A detailed comparison has been made between the angular distributions of the ground state 3He particles and of the tritons from the mirror reaction 12C(α, t)13N (1969GA11, 1972HA08). See also (1974HA32; theor.).
Angular distributions have been reported at E(14N) = 78 MeV (1970VO02; transitions to both g.s., and also 13N(0) + 13C*(3.85)), 100 MeV (1974DE03: to 13C*(0, 3.09, 3.68 + 3.85, 7.3 ± 0.3 [may be due to 6.86 + 7.50 + 7.55 + 7.68]) and 154.8 MeV (1975NA15, 1975VO05, 1976NAZZ: to g.s. and 3.85). The ratio of the differential cross section to 13Cg.s. and that to 13Ng.s. (observed via 12C(14N, 13C)13N), as a function of θ, is approximately 1 as expected if mirror symmetry holds (1969VO01, 1970VO02, 1975VO05). See also (1970JA1B, 1973BR1C, 1973SC1J, 1973VO1E, 1974AN36, 1974SC1M, 1975HA1P) and (1970AN1D, 1973DE02, 1973DE35, 1974BR18, 1974BR37, 1975RE04; theor.).
The cross section exhibits structure at 13.3 ± 1 [Γ = 5 ± 1 MeV] and at ≈ 22 MeV [Γ ≈ 7 MeV] (1957CO57, 1975PA09, 1976MC1L). Indications of structures at other Ex are reported by (1965BE1A, 1970FU09, 1976JU1A, 1976MC1L). 12C*(15.11) [Jπ = 1+; T = 1] is populated to a large extent by neutrons emitted from the T = 3/2 component of the giant resonance in 13C (1971MU11). 12C*(4.4) is populated most strongly at 13C*(13.3) (1975PA09). See also (1973AR1L), (1974KI03, 1974MA10; theor.) and (1973FR1F; applied). For reaction (b) see (1975PA09, 1976MC1L).
(1964DE12) report structures at Eγ = 18.5, 20.0, 23.5, 26.0 and 29.0 MeV. The main part of the cross section is in the 23.5 MeV peak which has Γ ≈ 3 MeV. A broad maximum near 25.5 MeV has been reported by (1956CO72, 1957CO57). The cross section to 12B*(0.95) shows a broad maximum at Eγ = 25 MeV (1975PA09). See also (1974KI03; theor.).
The radius of 13C, rrms = 2.452 ± 0.047 [relative to rrms of 12C = 2.462 ± 0.022 fm] (1973FE13). See also (1967CR1C, 1970HE24, 1971BE25, 1971YA02) and (1970BR1C). The rms radius of the magnetization distribution of 13C = 3.3 ± 0.3 fm (1975LA23). The elastic scattering has been studied for Ee = 120 to 750 MeV (1970HE24). A number of inelastic groups are seen: see Tables 13.20 (in PDF or PS) and 13.21 (in PDF or PS) (1970WI04, 1971BE51, 1971YA02). A distinct splitting of the giant resonance into two large peaks near Ex = 20.5 and 24.5 MeV, with widths of ≈ 3 and ≈ 4 MeV, respectively, is observed. It is suggested that these are groupings of narrower peaks [see Table 13.21 (in PDF or PS)]. The Ex = 20.5 and 24.5 MeV resonances are probably T = 1/2 and T = 3/2, although the 4 MeV splitting is somewhat smaller than expected (1971BE51). See also reactions 50 and 51. See also (1970BR1C, 1972THZF, 1974DE1E, 1975BE1T, 1975SI1H) and (1970BE1G, 1970TI1C, 1973GA19, 1974BE10; theor.).
Angular distributions have been studied at Ep = 1.37 to 2.38 MeV (1966GE03; p0), 6.36 and 6.48 MeV (1971VA29; p1), 7 MeV (1969GU02) and 30.4 MeV (1972GR02; p0, p1). Angular distributions of the 3.09 MeV γ-rays are isotropic for Ep up to 5 MeV consistent with the assignment J = 1/2 for the ground state (1960BA35). For τm measurements see (1968RI16) and Table 13.5 (in PDF or PS). See also (1970OH1C, 1973KA04, 1974GU1D; theor.).
Reaction (b) has been studied at Ep = 7.9 to 12 MeV (1970OT1A, 1971OT02) and at Ep = 46 MeV (1974MI05). One or more 13C states at Ex = 7.5 MeV seem to be involved in the sequential decay (1971OT02). See also (1974AV02; theor.), 13N and 14N.
Angular distributions have been measured at Ed = 0.71 MeV (1971PU01; d0), 4.7, 5.0 and 5.3 MeV (1968CO04; d0), 12.8 MeV (1973VA07; d1), 13.7 MeV (1970GU01; d0, d1, d2+3) and 15 MeV (1974BU06). See also (1970LI1E), (1974GU1D; theor.) and 15N.
Angular distributions of elastically scattered 3He have been studied at E(3He) = 12, 15 and 18 MeV (1966KE08), 14 MeV (1970NU02), 35.7 MeV (1969AR08) and at 40 MeV (1969BA06). Angular distributions at E(3He) = 40 MeV have also been reported to 13C states at Ex = 3.09, 3.68, 3.85, 6.86, 7.55 ± 0.03, 8.86 ± 0.03 and 11.84 ± 0.03 MeV. 3He groups to 13C*(9.50 ± 0.03) and (15.11) are also reported: the latter is weak (1969BA06). See also (1974CH58; theor.).
Elastic angular distributions have been measured at Eα = 15, 18 and 20 MeV (1971CO14), 18 to 24 MeV (1973KU18), 18.3 MeV (1973LE28), 24 MeV (1974FE08), 26.6 MeV (1972KU19), 28.4 MeV (1965KO1A), 33.4 MeV (1967AR17) and 40.5 MeV (1966HA19). In addition, (1967AR17) report distributions to 13C*(3.68, 7.5), (1966HA19) to 13C*(3.09, 3.68 + 3.85, 7.5) and (1965KO1A, 1974FE08) to 13C*(3.09, 3.68 + 3.85, 6.85, 7.5). See also (1974CH58, 1974KU15; theor.).
Angular distributions of elastically scattered Li ions have been studied at E(Li) = 4.5, 5.8, 9.0 and 13 MeV (1976PO02; 6Li and 7Li [not 4.5]), 20 MeV (1969BE90; 6Li and 7Li), 28 MeV (1972BA52; 6Li) and 34 MeV (1973SC26; 6Li and 7Li). The inelastic scattering to 13C*(3.09) in reaction (a) has also been studied (1973SC26). See also (1971BA2V, 1972WA31; theor.).
Angular distributions for reaction (a) have been studied at E(12C) = 10 to 30 MeV (1968GO1H; elastic), 15 and 19 MeV (1971BO52, 1972BO68; elastic), 20 to 36 MeV (1973CH1L: to 13C*(0, 3.09, 3.68 + 3.85)) and 87 MeV (1971LI11; elastic). See also (1971WI1J, 1972CH1H, 1974CR03), (1970GO1B, 1973BR1C, 1973SC1B, 1974GO1L), (1970VO1D, 1973BA2K, 1973DE35, 1973MC1J, 1973SA1K, 1973VO04, 1974GA1L, 1974IM1B, 1975DE09, 1975VO1B; theor.) and 12C in (1975AJ02).
For reaction (b), elastic angular distributions have been measured at E(13C) = 15 to 24 MeV (1973HE12), while for reaction (c) the elastic distribution has been measured at E(13C) = 15 MeV (1972BO68). See also (1972HA2B), (1974GO1L) and (1973MC1J, 1973VO04, 1975DE09, 1975VO1B; theor.).
Elastic angular distributions have been measured for reaction (a) at E(16O) = 10 to 30 MeV (1968GO1H) and 14, 17 and 20 MeV (1970BA49) and at E(13C) = 36 MeV (1975WE1D, 1975RA33), and, for reaction (c), at E(18O) = 15, 20 and 24 MeV (1971KN05). See also (1974CH1Q). For reaction (b) see (1974CH1Q). See also (1974BE1J; theor.).
Angular distributions have been measured at Ep = 12 MeV (1966GL01; d0), 14.5 MeV (1971CU01; d0, partial d2), 18.5 MeV (1963LE03; d1, d2, d3) and 27 MeV (1975CE04; d0 → d3). The spectroscopic factors for 13C*(0, 3.09, 3.68, 3.85) are 1.4, 0.02, 1.8 and 0.13, respectively (1975CE04).
Angular distributions have been studied at Ed = 12 MeV (1966GL01; t0 → t3) and 14 MeV (1976WE01; t0 → t3; polarized deuterons). The spectroscopic factors for 13C*(0, 3.09, 3.68, 3.85) are 1.00, 0.06, 1.0 and 0.08, respectively (1976WE01). See also 16N in (1977AJ02).
See (1972KU1H; theor.).
For Ebs = 15.5 to 29.5 MeV a large fraction of the neutron yield appears to be associated with sequential decay to 12C via 13C*(7.75, 8.86, 11.80) (1970SH06, 1972GE11). Angular distributions measured in the giant resonance region of 14N are consistent with the proton decay of (p1/2)-1 (2s1d) giant dipole states to 13Cg.s. and of (p3/2)-1 (2s1d) states to 13C*(3.68) (1974BA37). The population of 13C*(3.09, 3.85) has also been reported (1970TH01: Ebs = 29 MeV). See also 14N and (1973KI05; theor.).
Angular distributions of d0 have been determined at En = 14.1 to 14.7 MeV: see (1970AJ04). See also (1971MI12). Gamma rays with energies of 3.686 and 3.853 MeV are reported by (1971NY03: ± 3 keV). Differential cross sections for formation of 13C*(3.09, 3.68) have been measured for En = 10.1 to 11.0 MeV by (1970DI1A). See also 15N and (1970BO1K; theor.).
For reaction (a) see (1969BA1F). At Ep = 46 MeV, the summed proton spectrum shows transitions to 13C*(0, 3.68, 7.5, 11.9) (1970WE09, 1970WE1J). At Ep = 460 MeV 13C*(0, 7.8, 12.3) are populated: the two excited states are formed by ejection of p3/2 protons. There is also some indication of other structure (1966TY01). See also (1972CH21, 1973DE1T; theor.).
At Ed = 52 MeV, angular distributions have been measured for the 3He particles to 13C*(0, 3.09, 3.68, 6.86, 7.5, 8.86, 9.50, 11.9 ± 0.15) and analyzed by DWBA: Jπ = 5/2-, 1/2-, 3/2- and 3/2-, respectively, are assigned to 13C*(7.5, 8.86, 9.50, 11.9) (1968HI01). As expected, angular distributions of 3He and of tritons (from 14N(d, t)13N) to analog states are closely the same: this has been shown for the ground state 3He and triton groups (1966DE1C, 1968GA13: Ed = 28.5 MeV; (1974LU06): Ed = 15 MeV) and for the groups to 13C*(8.9 + 9.5) and 13N*(9.2) (1968HI01: Ed = 52 MeV). See also 16O in (1977AJ02) and (1974DA1D; theor.).
This sequential reaction has been studied at Eα = 22.9 MeV (1969BA17).
An angular distribution has been obtained at E(6Li) = 32 MeV for the transition to 13Cg.s. and 7Be*(0, 0.43) [for the mirror reaction see reaction 38 in 13N]: the relative cross sections show a deviation from isospin symmetry which is attributed to Coulomb effects. 13C*(3.09) was also populated (1971GR44, 1971ZE1C).
At Ep = 43.7 MeV, 3He groups have been observed to eleven states of 13C: see Table 13.22 (in PDF or PS) (1966CE02, 1968FL03). Angular distributions of the 3He particles to these states are generally found to be in agreement with DWBA predictions, using intermediate coupling wave functions to obtain the two-nucleon structure factors (1968FL03). Detailed comparisons are made with the results of the mirror reaction 15N(p, t)13N: the (p, t) transitions are generally stronger than expected relative to the mirror (p, 3He) transitions. This may arise from interference effect terms due to a spin-orbit interaction in the optical potential, or to interference terms between direct-reaction and core excitation (1968FL02, 1968FL03). A study of both angular distributions and analyzing powers in this reaction and in the mirror (p, t) reaction shows that DWBA generally fails to predict the analyzing powers (1974MA12: Ep = 43.8 MeV; pol. protons). Angular distributions have also been measured for the 3He groups to 13C*(0, 3.68, 7.55) at several energies in the range Ep = 24.0 to 43.5 MeV (1974PI05, 1975MI01). See also (1969TE1A, 1972HA1X) and 16O in (1977AJ02).
Alpha-particle groups have been observed to excited states at Ex = 3.083 and 3.677 MeV (1951MA08: ± 5 keV) and 8.80 ± 0.04 MeV (1957WA01: other states were excited but their Ex were not determined). Angular distributions of α0 have been measured at Ed ≈ 1 MeV and ≈ 21 MeV: see (1970AJ04). See also (1967SP09).
At Eα = 42 MeV, the angular distribution of the 6Li particles to 13Cg.s. has been measured (1968MI05).
See (1972KU1H; theor.).
Angular distributions have been measured at many energies. The earlier results are listed in (1970AJ04). Recent measurements have been carried out at En = 4.9 MeV (1972KI12; α0), 13.9 MeV (1971BR33; α0, α1, α2+3) and 14.1 MeV (1970AJ03; α1+2+3; (1973BO26); α0, α1+2+3). Excitation energies derived from γ-ray measurements are 3685 ± 3 and 3854 ± 3 keV (1971NY03). See also (1970DI1C) and 17O in (1977AJ02).
At Eα = 42 MeV the angular distribution of the reaction involving 13C(0) and 7Be*(0 + 0.43) has been measured by (1972RU03).