
^{13}C (1991AJ01)(See 13.4 [Table of Energy Levels] (in PDF or PS) and Energy Level Diagrams for ^{13}C) GENERAL: See also (1986AJ01), 2 [Electromagnetic Transitions in A = 1315] (in PDF or PS), 13.5 [Total radiation widths of lowlying levels of ^{13}C^{13}N] (in PDF or PS) and 13.6 [Parameters of the first T = 3/2 states in ^{13}C and ^{13}N] (in PDF or PS). Nuclear models:(1985KW02, 1987KI1C, 1988MI1J, 1988WO04, 1989AM02, 1989PO1K, 1989WO1E, 1990FE01, 1990HO01, 1990VA01). Special states:(1984KO40, 1985GO1A, 1985RO1J, 1985SH24, 1986AN07, 1986XU02, 1987KI1C, 1988KW02, 1988MI1J, 1988RO1R, 1988ZH1B, 1989AM02, 1989OR02, 1989RO03, 1990HO01). Electromagnetic transitions and giant resonances:(1984VA06, 1985GO1A, 1986AD1B, 1986ER1A, 1987KI1C, 1989AM02). Astrophysical questions:(1982BU1A, 1982CA1A, 1982GR1A, 1982WO1A, 1985BR1E, 1985HA1R, 1985HE1F, 1985MI1E, 1985PR1D, 1985RI1B, 1986DO1L, 1986FR1G, 1986GO1Q, 1986LA1C, 1986MA2E, 1986SN1C, 1986SN1D, 1986WI1H, 1987AR1C, 1987AU1A, 1987BE1H, 1987BO1B, 1987BR1P, 1987DO1A, 1987HA1C, 1987HA1U, 1987KR1M, 1987MA1C, 1987MA2G, 1987PI1E, 1987PR1A, 1987SO1F, 1987WA1L, 1987WA1F, 1987ZI1C, 1988AP1A, 1988AR1H, 1988AS1D, 1988CR1A, 1988DE1I, 1988JA1B, 1988JU1C, 1988PI1C, 1988SC1A, 1988TR1H, 1989AB1J, 1989BA2I, 1989BA2K, 1989BO1S, 1989BR1I, 1989BR1M, 1989CH1X, 1989CH1Z, 1989FR1J, 1989GI1E, 1989GU1L, 1989HA1O, 1989HO1F, 1989JI1A, 1989KA1K, 1989LO1C, 1989LO1D, 1989ME1C, 1989NO1A, 1989SM1A, 1989ST1K, 1989WE1G, 1989WH1B, 1989WY1A, 1990CA1O, 1990FU03, 1990HO1I, 1990MO1I, 1990PI1F, 1990TU1A, 1990WE1I). Applied work:(1986BR1Q, 1986BU1H, 1986DO1M, 1986DR1E, 1986EN1A, 1986FO1D, 1986FR1H, 1986GE1C, 1986HE1F, 1986KI1J, 1986KN1E, 1986KR1F, 1986MA2D, 1986MA2G, 1986NI1C, 1986NO1C, 1986SR1B, 1986ST1K, 1986XU1C, 1987BO1U, 1987DU1A, 1987KI1I, 1987NA1O, 1987ST1C, 1988AR1G, 1988BU1C, 1988DO1D, 1988FA1A, 1988GO1J, 1988MA1A, 1988PU1A, 1988SC1C, 1989CE1D, 1989GR1F, 1989KU1P, 1989MU1A, 1989RA1M, 1990DO1C, 1990FR1F). Complex reactions involving ^{13}C:(1984BO1H, 1985KI1E, 1985KW03, 1985PO11, 1985PO14, 1985UT01, 1986AV1B, 1986GR1A, 1986HA1B, 1986HO1K, 1986MA19, 1986MA1O, 1986ME06, 1986MO15, 1986PO06, 1986SA30, 1986SO10, 1986UT01, 1986XU02, 1986XU1B, 1987AR19, 1987BA38, 1987BE1I, 1987BU07, 1987GA17, 1987GE1B, 1987LY04, 1987NA01, 1987PE1B, 1987PO23, 1987RI03, 1987SI1C, 1987SN01, 1987ST01, 1987VI02, 1987YA16, 1988BE56, 1988CA06, 1988GA11, 1988HA03, 1988JO1B, 1988KI06, 1988RU01, 1988SA19, 1989AJ1A, 1989BA92, 1989CH1U, 1989GIZV, 1989GRZQ, 1989HO16, 1989KI13, 1989POZT, 1989PR02, 1989SA10, 1989SE03, 1989TE02, 1990CH09). Muon and neutrino capture and reactions:(1985DE42, 1985KO39, 1985MI21, 1986IS02, 1986MI09, 1986MI1M, 1987SU06, 1990CH13, 1990FU03, 1990LU1D, 1990MI1J). Pion capture and reactions involving pions and ρmesons (See also reactions 27 and 41, and reaction 23 in ^{13}N): (1983MA16, 1984BO1H, 1984CH1K, 1985SA06, 1986BO1N, 1986CE04, 1986DO01, 1986ER1A, 1986KO26, 1986LI1N, 1986LI1P, 1986MI1M, 1986SI07, 1986SI13, 1986SI22, 1986SU18, 1987DU08, 1987GI1C, 1987MI08, 1987PI1B, 1988BU1I, 1988CH24, 1988CH1L, 1988CHZU, 1988GIZU, 1988HA12, 1988KIZW, 1988PE1F, 1988PE1H, 1988PO1H, 1988POZV, 1988US01, 1989CH31, 1989GE10, 1989IT04, 1989JE02, 1989JO07, 1989KI25, 1989MO09, 1989PI11, 1990BE12, 1990CH12, 1990ER03, 1990ER1E, 1990FE01, 1990KO19, 1990TA1K, 1990TI1B). Kaon capture and reactions:(1984BO1H, 1985GA1C, 1986DO01, 1986FE1A, 1986GA33, 1986MA1C, 1986MA1W, 1987FA1A, 1987PI1B, 1987PO1H, 1988FA1B, 1988PE1F, 1988PE1H, 1988PO1H, 1988ZH1H, 1989CH52, 1989DO1K, 1989PI11, 1990FE01). Hypernuclei:(1984BO1H, 1984ZH1B, 1985BA1F, 1985BA2D, 1985GA1C, 1985KO1W, 1985KO2B, 1985YA1C, 1986AN1R, 1986BA1H, 1986DA1G, 1986DA1B, 1986DO01, 1986ER1A, 1986FE1A, 1986GA33, 1986KO1A, 1986LA1R, 1986MA1C, 1986MA1W, 1986ME1F, 1986WU1C, 1986WU1D, 1986YA1F, 1987CO1E, 1987FA1A, 1987MA08, 1987MI38, 1987PI1C, 1987PO1H, 1988CH48, 1988FA1B, 1988GA1A, 1988GA1I, 1988IT02, 1988MA1G, 1988MA58, 1988MO1L, 1988PE1H, 1988PO1H, 1988TA29, 1988WA1B, 1988ZH1H, 1989BA92, 1989BA93, 1989CH52, 1989DO1K, 1989DO1N, 1989FE07, 1989IT04, 1989KI25, 1989KO1H, 1989KO37, 1989KO48, 1989LA1H, 1989LA1I, 1989MA30, 1989MI30, 1989PI11, 1990FE01, 1990IT1A, 1990OS1A). Other topics:(1985AN28, 1985SH24, 1986AN07, 1988KW02, 1989FU05, 1989OR02, 1990MU10). Ground state of ^{13}C:(1985AN28, 1985GO1A, 1986GL1A, 1986SI22, 1987AB03, 1987FU06, 1987GI1C, 1987KI1C, 1987SA15, 1988AR1I, 1988KE1B, 1988VA03, 1988WA08, 1988WO04, 1989AM02, 1989AN12, 1989FU05, 1989GOZQ, 1989WO1E, 1990VA01).
< r^{2} > ^{1/2} = 2.4628(39) fm (1985DE42) [charge radius, from muonic ^{13}C] [The neutron r.m.s. radius is 2.35 (3) fm (1979JO08).] Natural abundance:(1.10 ± 0.03)% (1984DE53) ^{13}C*(3.85): g = 0.558 ± 0.015 (1981RU04). From the γray due to the transition ^{13}C*(3.85 → 3.68), ΔE_{x} = 169.356 ± 0.020 keV: see (1986AJ01). See also (1989RA17).
The yield curves for d_{0} (E(^{6}Li) = 4 to 14 MeV), T_{0} (E(^{7}Li) = 5 to 14 MeV) and α_{0} (E(^{6}Li) = 4 to 14 MeV) show broad, uncorrelated structures. Energyaveraged differential cross sections are also reported for a number of ^{12}B, ^{11}B and ^{10}B states. Total cross sections have been measured for E(^{7}Li) = 3.8 to 6.0 MeV for p_{0} → p_{2}, p_{3+4}, p_{5}; d_{0} → d_{3}, d_{4+5}, d_{6}; t_{0} → t_{2}; and α_{0}: the total cross sections generally increase smoothly with energy without showing any structure: see (1981AJ01). For reaction (b) see (1987SC11).
Resonances for n_{0} and n_{1}, for γrays from ^{12}C*(4.4, 12.7, 15.1) and resonances in the total neutron cross section are given in 13.7 (in PDF or PS). In addition the yield of neutrons to ^{12}C*(7.65, 9.64) has been measured in the range E_{α} = 2.9  6.4 MeV. The n_{0} and n_{1} excitation functions exhibit weak resonance anomalies at E_{α} = 6.44 MeV corresponding to the J^{π} = 3/2^{}, T = 3/2 state at E_{x} = 15.11 MeV: see 13.6 (in PDF or PS) and 13.7 (in PDF or PS) (1978HI06). For thick target yields see (1982WE16). See also (1989HE04). For polarization measurements (E_{α} to 100 MeV) see (1981AJ01). Reaction (b) has been studied at a number of energies for E_{α} = 17 to 44 MeV: see (1981AJ01, 1986AJ01). See also ^{12}C in (1990AJ01), (1987EL1B, 1989CR07; applied) and (1985CA41; astrophysics).
Excitation curves have been measured for E_{α} = 15 to 27.5 MeV for reaction (a) [involving d_{0}, d_{1} and at the higher energies d_{2}, d_{3}, d_{4+5}, d_{6}] and at 26.0 to 27.5 MeV for reaction (b) [t_{0}, t_{1}, t_{3}]: no structures are observed: see (1981AJ01). See also ^{11}B in (1990AJ01) and (^{10}B in 1988AJ01).
A number of excitation functions have been measured for elastically scattered αparticles for E_{α} = 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. The parameters resulting from a bestfit of the excitation functions are displayed in 13.8 (in PDF or PS): see the footnotes to that table for a summary of the most important caveats. A weak resonance is observed in the α_{0} yield at E_{α} = 6.44 MeV corresponding to the excitation of the first T = 3/2 state at E_{x} = 15.11 MeV: see 13.6 (in PDF or PS) for the parameters of that state. For a measurement of the total reaction cross section at E_{α} = 100 MeV see (1986DU15). See also (1987BU27) and (1986SA30; theor.).
Angular distributions have been studied at E(^{6}Li) = 32 MeV to ^{13}C*(0, 3.09, 3.68 + 3.85, 6.86, 7.5, 9.5, 9.9, 10.75, 13.42). The spectra are dominated by the deuteron group to a state (or states) at E_{x} = 10.75 ± 0.018 MeV, with Γ = 130 keV [suggesting that both ^{13}C*(10.75, 10.82) are populated]. Two states, consistent with ^{13}C*(11.35, 12.13) are also populated, as is a broad group at 14.13 MeV (1989AS01; see for spectroscopic factors).
Angular distributions for t_{0}, t_{1}, t_{2+3}, T_{4} are reported at E(^{7}Li) = 5.6 to 6.2 MeV: see (1976AJ04).
Cross sections for gamma rays from the decay of ^{13}C*(3.09, 3.68, 3.84) are reported by (1988LA25) for E(^{9}Be) = 2.8 to 6 MeV.
Angular distributions have been measured for E(^{12}C) = 10.5 to 15 MeV and at E(^{9}Be) = 20 MeV: (see 1981AJ01, 1986AJ01).
Yields have been measured for E_{t} = 0.5 to 2.0 MeV. There is no evidence of resonance behavior: see (1981AJ01). In the range E_{t} = 3.0 to 7.3 MeV a broad structure is reported in the activation cross section (reaction (a)) at E_{t} ≈ 5.5 MeV, Γ ≈ 2.7 MeV (1985AB10). See also ^{9}Be in (1988AJ01).
At E(^{3}He) = 260 and 280 MeV, ^{13}C_{g.s.} and an unresolved group at E_{x} ≈ 3.6 MeV are observed: see (1986AJ01).
Angular distributions have been measured at many energies up to E_{α} = 31.2 MeV: see (1970AJ04, 1986AJ01). For γdecay measurements see 13.6 (in PDF or PS). At E_{α} = 218 MeV, ^{13}C*(0, 3.09, 3.7, 6.9, 7.6, 9.9) are populated (1987BI1C; prelim.). For a study of high E_{x} states see (1987BRZV, 1987MIZY, 1988BRZY; prelim.). See also ^{14}N, (1989BR1J) and (1986BA58; axion search).
Comparisons of the relative intensities of the ^{3}He groups in this reaction and of the triton groups in the mirror reaction (see reaction 6 in ^{13}N) at E(^{6}Li) = 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) E_{x} is in ^{13}C, the second in ^{13}N]: see (1981AJ01).
Angular distributions have been measured at E(^{7}Li) = 5.20 MeV for the α_{0}, α_{1}, α_{2+3} and α_{4} groups: see (1981AJ01).
At E(^{10}B) = 100 MeV angular distributions are reported for the transitions to ^{13}C*(0, 3.7, 7.5, 11.8): see (1981AJ01).
The 90° γ_{0} excitation curve measured for E_{d} = 1.0 to 12.0 MeV shows resonant structure at E_{d} = 2.0 ± 0.1 and 4.0 ± 0.1 MeV, Γ ≈ 0.6 and ≈ 1 MeV, corresponding to states at E_{x} = 20.4 and 22.1 MeV: see 13.9 (in PDF or PS) and (1986AJ01). More recently (1985AU10) have studied the 90° γ_{0} differential cross sections at E_{pol. d} = 1.65 to 3.5 MeV, angular distributions at 1.6, 1.8, 2.0 and 4.0 MeV, and analyzing powers at E_{pol. d} = 2.0 and 4.0 MeV (90°) and 1.6 and 1.8 MeV (125°). The data are interpreted in terms of two doorway states at E_{x} = 20.57 ± 0.84 and 20.20 ± 0.07 MeV with Γ_{c.m.} = 5.64 ± 0.43 and 0.56 ± 0.09 MeV, respectively (1985AU10). See also reaction 22 and (1990HO06).
The yields of neutron and 15.1 MeV γrays have been measured in the range E_{d} = 0.2 to 11 MeV: see 13.9 (in PDF or PS). At E_{pol. d} = 79 MeV, VAP measurements are reported for ^{12}C*(0, 4.4, 9.6, 12.7, 15.1) (1987FO22, 1986FO08). See also (1981AJ01). The thicktarget yield in reaction (b) has been measured for E_{d} = 7.00 to 16.01 MeV: see (1986AJ01). See also ^{12}C in (1990AJ01).
For reaction (a) see also (1981AJ01, 1986AJ01). For E_{d} = 2.99 to 6.99 MeV the activation cross section does not show any evidence of structure (1985AB10). For reaction (b) see (1981AJ01). See also ^{12}B in (1990AJ01).
At low energies the excitation functions for α_{0} and α_{1} increase monotonically: see (1970AJ04). Then at E_{d} = 1.85 MeV a pronounced resonance is observed in the α_{0}, α_{1}, α_{2} and α_{3} yields: see 13.9 (in PDF or PS). Some gross structure is also observed in these yields for E_{d} = 1.0 to 3.2 MeV: see (1981AJ01). See also ^{9}Be in (1988AJ01).
Levels derived from proton groups are displayed in 13.11 (in PDF or PS) of (1981AJ01). [The only level parameters included in the values of 13.4 (in PDF or PS) are E_{x} = 7500 ± 12 keV and Γ_{c.m.} < 5, 70 ± 10 and 150 ± 30 keV for ^{13}C*(7.49, 7.69, 8.86).] The neutron decays of ^{13}C*(6.86, 9.90, 11.75) are to ^{12}C_{g.s.} (99 ± 9)% and (100 ± 20)% for the first two states, and to ^{12}C*(0, 4.4) (67 ± 16)% and (33 ± 8)% for the third (1973AD02). The decay parameters for the first T = 3/2 state, ^{13}C*(15.11), are shown in 13.6 (in PDF or PS). See also (1986AJ01).
Angular distributions have been measured at E_{α} = 15.1 to 31.2 MeV: see (1981AJ01, 1986AJ01). See also (1987BRZV) and (1984BE23; theor.).
For reaction (a) see (1981AJ01). For reaction (b) see ^{5}He in (1988AJ01) and ( 1990DA03).
The thermal capture cross section is 3.53 ± 0.07 mb. The capture is (67.47 ± 0.92)%, (0.16 ± 0.01)% and (32.36 ± 0.44)% via ^{13}C*(0, 3.09, 3.68): see (1986AJ01) for references and additional information. Based on unpublished measurements quoted in (1986AJ01), the energies of the γrays involved in C → 0, C → 3.68 and 3.68 → 0 are 4946.362 ± 0.021, 1261.855 ± 0.006 and 3684.507 ± 0.019 keV. The branching ratios for the decay of ^{13}C*(3.68) to ^{13}C*(0, 3.09) are (99.3 ± 2.0)% and (0.74 ± 0.05)%, respectively: see (1986AJ01). (1990WA22) proposes 3683.915 ± 0.015 keV for E_{γ}[3.68 → 0]. Differential cross sections for γ_{0} (90°) have been studied for E_{n} = 6.5 to 18.5 MeV (1987AU02), 7.0 to 19.5 MeV (1986BE17) and at 7.8, 9.3 and 10.8 MeV (1990HA19). Broad structures are seen at ≈ 9 and 17.2 MeV (^{13}C*(13.2, 20.8)) [the latter has Γ ≈ 2.5 MeV]. It should be noted that the cross sections reported by (1987AU02) are substantially higher than those reported in the other two references. The variation of the cross section with energy is similar to that from the ^{13}C(γ, n_{0}) reaction but the magnitudes of the cross section are smaller: see, for instance, (1990HA19). Angular distributions and analyzing powers of γ_{0} for E_{n} = 12.0 to 18.8 MeV suggest two doorway states at E_{x} = 21.1 ± 0.6 and 20.52 ± 0.07 MeV with Γ = 4.2 ± 0.4 and 0.51 ± 0.07 MeV, respectively (1984WO05). See also (1989HU15). For work to 50 MeV see (in 1988DO1E; prelim.). See also (1986MU1B, 1986RA1B, 1986WE1D, 1988MCZT), (1988MA1U, 1989GU1J; astrophysics) and (1987HO23, 1987LY01: theor.).
The coherent scattering length (thermal, bound) a_{coh} = 6.6535 ± 0.0014 fm; σ_{scatt} = 4.7456 ± 0.0020 (1979KO26). Total cross sections have been measured in the range E_{n} = 1 keV to 273 GeV/c [see (1981AJ01, 1986AJ01)] and at 0.14, 1.3 and 2.1 MeV (1988KO18) and 160 to 575 MeV (1988FR23): see the compilation of (1988MCZT). See also (1986BA40). Various elastic, inelastic and nonelastic cross sections have been reported over a wide range of energies: [see (1986AJ01, 1988MCZT)], most recently at 6.23 to 13.75 MeV (1986BO1M; prelim.; elastic and inelastic scattering cross sections), from 16.5 to 22.0 MeV (1989OL02, 1989OL1C; σ_{t}, σ_{el} and σ to ^{12}C*(4.4, 7.7, 9.6)) and from threshold to 25 MeV (1988WE06; prelim.; cross section for scattering to ^{12}C*(4.4)). Polarization measurements have been reported for E_{n} = 1.5 to 16.3 MeV [see (1976AJ04, 1981AJ01, 1986AJ01)] and at E_{n} = 15.55 to 17.35 MeV (1987TO03, 1987TO07) and 18.2 MeV (1988TO01). See also (1986BE2D, 1987BEYP). Observed resonances are displayed in 13.10 (in PDF or PS) here, and in 13.13 (in PDF or PS) in (1981AJ01) [the latter for (n, n'γ_{4.4})]. In 13.10 (in PDF or PS) the assignment of the broad states above E_{x} = 11.7 MeV are from phaseshift analyses (σ(θ) and A_{y}) referred to here and in (1986AJ01). Five weak anomalies in the total cross section are thought to be due to T = 3/2 states (1987HI03). For reactions (c) and (d) see reactions 23 and 24 in (1986AJ01) and (1988MCZT). For pion production see (1988BU16). See also ^{12}C in (1990AJ01) and (1984BE1L, 1985FI09, 1985KU1F, 1985ME16, 1985RA1E, 1986BAYL, 1986DR10, 1986ROZW, 1987NEZY, 1988AN1F, 1989SA1J), (1986AL1N, 1986WE1B, 1986WI1B, 1989OL1C; applied), (1988FR1M; astrophys.), (1987BR06, 1988MA1H) and (1985KO1U, 1985TI07, 1986BE2F, 1986LI16, 1988BA1P, 1988RU1C, 1989MI20, 1990LE1Q; theor.).
The cross section exhibits a weak resonance corresponding to E_{x} ≈ 20.5 MeV and a stronger structure at E_{x} ≈ 21.5 MeV: see (1976AJ04). See also the compilation of (1988MCZT). The excitation function for E_{n} = 30 to 150 MeV is being studied (1988RAZX; prelim.). For proton production for E_{n} = 300 to 580 MeV see (1987FR16). See also ^{12}B in (1990AJ01) and (1985AZ1A, 1986FO1E, 1989BE2P, 1989SOZY), (1986RO1F; applied), (1988FR1M; astrophysics), (1988MA1H) and (1986KO26, 1988PE01; theor.).
For deuteron and triton emission at E_{n} = 300 to 580 MeV, see (1987FR16). See also (1986RO1F; applied), (1988FR1M; astrophysics), (1988MA1H) and (1986KO26; theor.).
The cross section for the α_{0} group shows a broad structure at E_{n} ≈ 8 MeV: see (1981AJ01). For other work see (1986AJ01, 1988MCZT). See also (1988CA1I), (1986RO1F, 1986WI1B; applied) and (1988MA1H).
Angular distributions have previously been reported for E_{p} = 147 to 250 MeV: see (1986AJ01). ^{13}C*(0, 3.09, 3.68, 3.85, 6.86, 9.50) have been populated. In the more recent work at E_{p} = 354 MeV it is found that at 21° the π^{+} spectrum is dominated by the group to the (2p1h) 9/2^{+} state at 9.50 MeV. Angular distributions have been measured to ^{13}C*(0, 3.09 + 3.68 + 3.85, 9.50) (1987HU08) [see also for a discussion of the energy dependence of the total cross section, and of the influence of the Δresonance]. (1987HO21) report a measurement of groundstate differential cross sections at E_{p} = 186 MeV. At E_{pol. p} = 200 MeV angular distributions and A_{y} measurements have been reported to ^{13}C*(0, 3.09, 3.7[u], 6.86, 7.5[u], 9.5, 21.4) (1989KO21). For the strongly populated group to ^{13}C*(21.4) A_{y} ≈ 0 at all angles. The results are suggestive of those for a 7/2^{+}; T = 3/2 state, but other explanations are also possible (1987KO01, 1989KO21). See also (1990JAZZ). For inclusive differential cross sections and A_{y} at E_{ pol. p} = 400 and 450 MeV see (1986FA03). For other polarization measurements see (1986AJ01). For total cross sections at E_{p} = 180 and 201 MeV see (1985BI04). See also (1981AJ01), the "General" section, (1987SEZY, 1988SEZT), (1986JA1H) and (1985IQ01, 1986MI09, 1987KU06; theor.).
Measurements of proton groups and γrays are summarized in 13.11 (in PDF or PS). Angular distributions have been studied at many energies to E_{d} = 80.2 MeV [see (1981AJ01, 1986AJ01)] as well as at E_{pol. d} = 12 MeV (1988LA03; to ^{13}C*(0, 3.09, 3.68, 3.85, 6.86, 7.50, 7.55, 7.69)) and at E_{d} = 30 MeV (1986OH01; to all evenparity states below E_{x} = 10 MeV and to ^{13}C*(0, 3.68, 7.55, 10.75, 11.08)). See also (1989BE2K, 1989IE01, 1989NA1R). For τ_{m} measurements see 13.5 (in PDF or PS) and for γdecay see 13.6 (in PDF or PS). For work at very high energies see (1987AZ1C, 1989AV02). See also ^{14}N, (1985LI1H, 1988VI1A, 1989VI1E, 1990CH1J; applied), (1986SI1D; computer program) and (1984BL21, 1986IS1F; theor.).
At E_{t} = 38 MeV angular distributions have been measured to ^{13}C*(0, 3.09, 3.68, 3.85, 6.86, 7.5, 7.69, 8.2, 9.5, 10.7) (1988SI08). See also (1981AJ01).
At E(^{3}pol. He) = 33 MeV ^{13}C*(3.85) is strongly populated. ^{13}C*(0, 8.0 (broad), 9.5) have also been studied (1986KA44). See also (1981AJ01) and ^{15}O.
Angular distributions of the ^{3}He particles to the first three states of ^{13}C have been measured in the range E_{α} = 56 to 139 MeV. The groundstate distributions in this, and in the mirror reaction ^{12}C(α, t)^{13}N, have also been compared: see (1981AJ01). See also (1989KU1E; E_{α} = 94 MeV; g.s.; prelim.) and (1989GA1H).
At E(^{7}Li) = 34 MeV angular distributions have been studied to ^{13}C*(0, 3.09, 3.85). The analysis by FRDWBA leads to S = 0.65 ± 0.06, 0.75 ± 0.08 and 0.68 ± 0.10, respectively (1986CO02). See also (1988KE07; theor.). For the earlier work at E(^{7}Li) = 21.1 and E(^{7}Li) = 48 MeV see (1981AJ01, 1986AJ01).
At E(^{8}Li) = 14.3 MeV, an angular distribution is reported involving ^{13}C_{g.s.} (1989BE28): at θ_{lab} = 15°, the differential cross section is ≈ 15 mb/sr.
Angular distributions have been reported at E(^{12}C) = 72.5 and 93.8 MeV [see (1981AJ01, 1986AJ01)], at 240 MeV (1985BO39; ^{13}C*(0, 3.85)) and at 300, 420 and 600 MeV (1988WI09, 1989WI07; ^{13}C_{g.s.}). See also ^{11}C in (1990AJ01) and (1989SA44; theor.).
Angular distributions have been reported in the range E(^{14}N) = 28 to 154.8 MeV involving ^{13}C*(0, 3.09, 3.85, 7.3 ± 0.3): see (1981AJ01). See also 1986AJ01) and (1987OS1E, 1988KA27; theor.).
Angular distributions involving ^{16}O_{g.s.} + ^{13}C_{g.s.} are reported at E(^{17}O) = 40 to 70 MeV (1986FR04). For the earlier work see (1981AJ01). For reaction (b) see ^{18}O in (1987AJ02).
See ^{13}B and 13.2 (in PDF or PS).
The main features of the cross sections are a sharp peak corresponding to the T = 3/2 state ^{13}C*(15.11) [Γ_{γ0} = 19.7 ± 2.0 eV], the broad pigmy resonance at E_{x} = 13 MeV [on which peaks are superimposed at E_{x} = 11.0, 13.8, 16.5 and 17.8 MeV] and the giant resonance at E_{x} = 24 MeV (σ_{max} = 9.5 mb) [surrounded by shoulder resonances at E_{x} = 20.8 and ≈ 30 MeV, both of which appear to decay substantially to highly excited states of ^{12}C]. There is also some evidence for a weak resonance at ≈ 37 MeV superimposed on the highenergy tail of the GDR. A study of the angular distributions of n_{0} suggests states at E_{x} = 7.70 (3/2^{+}), 7.95 (3/2^{+}), 8.95((1/2^{})), 10.0 ((3/2^{})), 11.0 ((1/2^{+})) and 12.05 MeV ((3/2^{+})). See (1981AJ01) for references and for additional information. See also the atlas in (1988DI02), (1985PY01, 1988BE1T, 1988HA12) and (1985GO1A, 1987KI1C; theor.). For comparisons with ^{12}C(n, γ) see reaction 22 and (1985AU10, 1986BE17).
The integrated cross section (reaction (a)) from E_{γ} = 17.5 (threshold) to 28 MeV is 36 ± 5 MeV · mb. Resonances are observed at E_{x} = 18.6, (19.7), 20.7, (22), 23.5, 24.5 and (26) MeV. [σ_{max} at E_{x} ≈ 23 MeV is 8 mb]. Below ≈ 18 MeV the cross section is dominated by transitions involving T_{<} states. The states at 18.6 and 20.7 MeV have a significant T_{>} component. The two isospin components of the GDR appear to be split by 6.8 MeV (1983ZU02). For the earlier work see (1981AJ01). See also (1988HA12) and (1987KI1C; theor.). For the cross section of reaction (b) from detailed balance calculations from ^{11}B(d, γ) see reaction 15 and (1985AU10).
The elastic scattering has been studied for E_{e} = 80 to 750 MeV [see (1981AJ01, 1986AJ01)] and (1987HI09, 1989MI01). The form factor for M1 elastic scattering is enhanced above q ≈ 2.5 fm^{1} (1982HI07, 1987HI09). See also (1987DE43). A number of inelastic groups have been seen: see 13.12 (in PDF or PS) and 13.13 (in PDF or PS) (1970WI04, 1986HI06, 1987HI09, 1989MI01). A distinct splitting of the giant resonance into two large peaks near E_{x} = 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. The E_{x} = 20.5 and 24.5 MeV groups are probably T = 1/2 and T = 3/2, although the 4 MeV splitting is somewhat smaller than expected: see (1981AJ01). See also (1984CH1K, 1988SA06, 1986CH2E, 1986DO11, 1987HO23, 1988MI1J, 1989AM02, 1989WO1E, 1990JE1B; theor.).
Angular distributions have been measured at E_{π} = 20 to 180 MeV [see (1981AJ01) and 13.13 (in PDF or PS) in (1986AJ01)], at 65 MeV (1988MI02; several states up to E_{x} = 11.8 MeV) and at E_{π} = 30 and 50 MeV (1990SE04; elastic). Enhanced in π^{} scattering are ^{13}C*(0, 3.09, 3.85, 9.50, 21.60 ± 0.05), the latter very strongly but with a large uncertainty. Enhanced in π^{+} scattering are ^{13}C*(3.68, 7.55, 8.86, 11.82, 16.05 ± 0.05, 17.92 ± 0.05, 21.37 ± 0.05). The data for ^{13}C*(9.50, 21.60, 16.05, 21.37) indicate pure neutron particlehole excitations for the first two states and pure proton excitation for the latter two, however with large uncertainties except for ^{13}C*(9.5). Spin assignments are 9/2^{+} for ^{13}C*(9.50); 7/2^{+} or 9/2^{+} for ^{13}C*(16.05, 17.92, 21.37, 21.60); 5/2^{+} and/or 7/2^{+} for ^{13}C(11.82) [unresolved doublet?]. The π^{}/π^{+} asymmetry near 21.5 MeV suggests that there is isospin mixing between T = 1/2 and 3/2 states of J^{π} = 7/2^{+} and/or 9/2^{+} (1982SE04, 1983SE15). Analyzing powers for elastic scattering on pol. ^{13}C have been studied at E_{π±} = 100 MeV (1990SM1B) and 114 to 226 MeV (1990YE1C) [both preliminary]. See also the "General" section and (1986AMZX; theor.).
Angular distributions have been measured at E_{n} = 4.5 to 17.92 MeV [see (1986AJ01)], at 4.55 to 10.99 MeV (1989RE01, n_{0} → n_{3}) and at 24 MeV (1985PE10; n_{0}). At E_{n} = 8.1 to 11 MeV ^{13}C*(7.55) [J^{π} = 5/2^{}] is involved in the sequential decay to ^{12}C_{g.s.} (1987RE01). See also ^{14}C, (1988RE09; computer) and (1986AL1L; theor.).
Angular distributions have been studied at E_{p} = 1.37 MeV to 1 GeV [see (1981AJ01, 1986AJ01)] and at 30.95 MeV (1988BA30); p_{0}), 35 MeV (1986OH03: p_{0} → p_{3}), 71.8 MeV (1989VO05, 1990VO02; p_{0}; polarized protons), 135 MeV (1988CO05, to 33 states below E_{x} = 23 MeV), 500 MeV (1990HO06; p_{0}; polarized protons), 0.8 GeV (1985BL22; p_{0}) and 1 GeV (1985AL16; p_{0}). (1988CO05) assign 7/2^{+} for ^{13}C*(11.85) [in agreement with the (e, e) work]. (5/2^{+}) for ^{13}C*(11.95, 14.98), ≤ 5/2 for ^{13}C*(12.11, 12.19), (7/2, 9/2)^{+} for ^{13}C*(14.58, 21.47), (7/2^{+}) for ^{13}C*(16.08), (3/2, 5/2) for ^{13}C*(17.70), (3/2, 5/2)^{+} for ^{13}C*(18.70), (7/2, 9/2)^{+} for ^{13}C*(21.47), ≥ 5/2 for ^{13}C*(21.81) and ≤ 5/2 for ^{13}C*(22.2, 23). The widths of ^{13}C*(12.19 ± 0.01, 22.2 ± 0.1) are 110 ± 50 keV and 1100 ± 500 keV, respectively. [The widths for ^{13}C*(11.95, 12.11, 12.19) are appreciably smaller than those reported in 13.10. (in PDF or PS)] A state at E_{x} = 20.93 ± 0.1 MeV with Γ = 240 ± 100 keV is suggested (1988CO05, S. Collins, Ph.D. thesis, and B. Spicer, private communication). See also ^{14}N, (1985PE10) and (1986AMZX, 1986RA05, 1987BE1M, 1987BE1P, 1988GOZH, 1988RA08, 1989AM02, 1989AM05, 1989BEXT, 1989GO14, 1989KU14, 1989KU32, 1989RA1O, 1990DU01; theor.).
Angular distributions (reaction (a)) have been measured at E_{d} = 0.71 to 56 MeV: see (1981AJ01, 1986AJ01). See also ^{15}N. Angular distributions for the tritons to ^{13}C*(0, 3.09, 3.68, 3.85, 7.55) have been studied at E_{t} = 38 MeV (1988SI08). See also (1981AJ01).
Angular distributions of elastically scattered ^{3}He ions have been studied at E(^{3}He) = 12 to 41 MeV [see (1981AJ01)] and at 39.6 MeV (1987BUZR; prelim.) as well as at E(^{3}He) = 33 MeV (1986DR03). Angular distributions have also been reported at E(^{3}He) = 43.6 MeV for the ^{3}He ions to ^{13}C*(3.09, 3.68, 3.85, 6.86, 7.49 + 7.55, 7.69, 8.86, 9.50, 9.90, 10.75 + 10.82, 11.08, 11.85, 15.11, 16.0) [and these have been compared to the analog states reached in the ^{13}C(^{3}He, t)^{13}N reaction] (1981PE08). See also (1989DE1Q) and (1986ZE04, 1987RA36; theor.).
Angular distributions have been studied at E_{α} = 15 to 40.5 MeV [see (1981AJ01)], at E_{α} = 35.5 MeV (1981PE08; to ^{13}C*(3.09, 3.68, 3.85, 6.86, 7.49 + 7.55, 7.69, 8.86, 9.50, 11.08, 11.85)) as well as at E_{α} = 48.7 and 54.1 MeV (1987AB03; α_{0}). For ^{13}C*(7.69), E_{x} = 7686 ± 6 keV, Γ_{c.m.} = 70 ± 5 keV (1980FU04; also line shapes). An angular correlation study at E_{α} = 24.35 MeV of the (α, αn) reaction to ^{12}C_{g.s.} has determined the substate population of ^{13}C*(6.86), J^{π} = 5/2^{+} (1984DE44). Γ_{γ}/Γ ≤ 3 × 10^{4} for ^{13}C*(6.86). The evidence for states near 7.5 MeV is less clear cut (1985DE11). See also (1987BU27) and (1985SH1D; theor.).
Angular distributions of elastically scattered Li ions have been studied at E(Li) = 4.5 to 40 MeV [see (1981AJ01, 1986AJ01)] as well as at E(^{7}Li) = 34 MeV (1987CO02, 1987CO16). At E(^{7}Li) = 34 MeV angular distributions involving ^{13}C*(3.09, 3.68, 7.55) are also reported (1987CO02). For the (^{6}Li, αd) breakup via states of ^{17}O see (1986AJ01) and (1987CA30, 1989WUZX). For fusion and breakup cross sections see (1986AJ01). See also (1989DE34) and (1988DEZU, 1988DE1F; theor.).
The elastic scattering has been studied at E(^{13}C) = 28.1 and 36.2 MeV [see (1981AJ01)] and at E(^{9}Be) = 50.5 MeV (1990BA16; also to ^{13}C*(3.68, 7.55)). For cross section measurements see (1984DA17, 1986CU02). See also (1986MI24; theor.).
Elastic angular distributions have been measured at E(^{10}B) = 18 to 80.9 MeV: see (1986AJ01). For fusion and other cross section measurements see (1986AJ01) and (1988MA07). See also (1985CU1A).
Angular distributions for reaction (a) have been reported for E(^{12}C) = 10 to 87 MeV and E(^{13}C) = 12 to 36 MeV [see (1981AJ01, 1986AJ01)], and at E(^{12}C) = 94.5 MeV (and 1986BA80; elastic) and E(^{13}C) = 16.3 to 26.5 MeV (and 1988VO01; ^{13}C*(0, 3.09, 3.85)) and 260 MeV (and 1985BO39; ^{13}C_{g.s.} + ^{12}C*(0, 4.4)). Elastic distributions for reaction (b) have been studied at E(^{13}C) = 15 to 24 MeV [see (1981AJ01)] and at 14 and 16 MeV and (1988TR01). Angular distributions for reaction (c) have been measured at E(^{13}C) = 15 MeV [see (1981AJ01)] and at 20 to 27.5 MeV (and 1988BI11; ^{13}C(0, 3.09, 3.85)). For excitation functions, fusion and evaporation cross sections see (1986AJ01) and (and 1986HA30, and 1988TR01). For a spinflip probability study see (1985BY01) and ^{12}C in (1990AJ01). See also (1982BA1D, 1985BA1T, 1988TR01; astrophysics), (1984FR05, 1985BE1A, 1985CU1A, 1985KO1J, 1986SN1B, 1986ST1A, 1987GR1K, 1987IM1C, 1988BE1W, 1989VO1D, 1990VO1E) and (1985HU04, 1985IM1B, 1985SA1D, 1986BA1D, 1986BA69, 1986EL02, 1986HA13, 1986KA1B, 1986SA1D, 1986VI08, 1987AR1E, 1987BO48, 1987FR06, 1987IM01, 1987MA22, 1987TH04, 1988BR29, 1988JA14, 1988KA27, 1988MI25, 1988PA07, 1989ER1B, 1989FR08, 1989HA19, 1990BA03; theor.).
Elastic angular distributions have been measured at E(^{14}N) = 19.3 to 35 MeV and at E(^{13}C) = 105 MeV: see (1981AJ01, 1986AJ01). See also (1989BEZC: γray yields, reaction (b)) and (1986BA69; theor.).
Elastic angular distributions have been measured for reaction (a) at E(^{16}O) = 10 to 30 MeV and at E(^{13}C) = 36 and 105 MeV [see (1981AJ01)] as well as at E(^{16}O) = 42 to 65 MeV (1989FR04) and at 108.15 MeV (1986BA80). Those for reaction (b) are reported at E(^{17}O) = 29.8, 85.4, 120 and 140 MeV; and those for reaction (c) at E(^{18}O) = 15 to 31 MeV: see (1981AJ01, 1986AJ01). For excitation functions, breakup yields and fusion measurements see (1981AJ01, 1986AJ01) and (1983FR17 [see, however, (1988FR15)], 1985BE40, 1985BE37, 1986GA13, 1986PA10). See also (1985CU1A, 1985HU04, 1985KO1J, 1985RE1C, 1986ST1A, 1989BEZC, 1990SN1A) and (1985MI13, 1986BA69, 1986CI01, 1986MI1A, 1986PA04, 1987AR13, 1987BA01, 1987MO27, 1987DA34, 1987NU02, 1987RE1C, 1989CH2B, 1989TH1A, 1990IM01; theor.).
See (1986AJ01) and (1986OS05; theor.).
For reaction (a) see (1988SN1A). The elastic angular distribution for reaction (b) has been studied at E(^{13}C) = 60 MeV (1988YA06). For the earlier work see (1981AJ01, 1986AJ01). See also (1989CH1K; theor.).
For reaction (a) see (1990ME07); for (b) see (1988GO12, (1989RA1K). See also (1986AJ01).
See (1981AJ01, 1986AJ01) and (1985EL07, 1986OS05; theor.).
See ^{13}N.
See ^{14}C and (1985PY01). See also (1987GO09; theor.).
At E_{p} = 35.0 and 40.1 MeV angular distributions (reaction (a)) have been reported [and integrated cross sections and spectroscopic factors have been derived] for the deuterons to the 1/2^{} states ^{13}C*(0, 8.86, 11.08), the 3/2^{} states ^{13}C*(3.68, 9.90, 11.75, (13.28), 15.11), the 5/2^{+} states ^{13}C*(3.85, 6.86), the 1/2^{+} states ^{13}C*(3.09, 11.0), the 3/2^{+} states ^{13}C*(7.69, 8.2), ^{13}C*(7.5) [J^{π} = 5/2^{}] and ^{13}C*(9.50) [9/2^{+}] (1990YA01). See also (1981AJ01).
Angular distributions measured in the giant resonance region of ^{14}N are consistent with the proton decay of (p_{1/2})^{1} (2s1d) giant dipole states to ^{13}C_{g.s.} and of (p_{3/2})^{1} (2s1d) states to ^{13}C*(3.68). The population of ^{13}C*(3.09, 3.85) is also reported. For E_{b.s.} = 15.5 to 29.5 MeV a large fraction of the neutron yield appears to be associated with sequential decay to ^{12}C via ^{13}C*(7.75, 8.86, 11.80): see (1981AJ01). See also ^{14}N.
Angular distributions have been determined at E_{n} = 10.1 to 14.7 MeV: see (1981AJ01). See also (1988YOZX; E_{n} = 60 MeV; prelim.).
At E_{p} = 46 MeV, the summed proton spectrum shows transitions to ^{13}C*(0, 3.68, 7.5, 11.9): see (1981AJ01). At E_{p} = 50 MeV ^{13}C*(0, 3.1, 3.7) are populated (1984VD02, 1986VDZY). See also (1987VD1A).
At E_{d} = 52 MeV, angular distributions have been measured for the ^{3}He particles to ^{13}C*(0, 3.09, 3.68, 6.86, 7.5, 8.86, 9.50, 11.9 ± 0.15) and analysed by DWBA: J^{π} = 5/2^{}, 1/2^{}, 3/2^{} and 3/2^{}, respectively, are assigned to ^{13}C*(7.5, 8.86, 9.50, 11.9). [However, ^{13}C*(9.50) is known to have J^{π} = 9/2^{+}.] As expected, angular distributions of ^{3}He and of tritons (from ^{14}N(d, t)^{13}N) to analog states are closely the same: this has been shown for the groundstate ^{3}He and triton groups as well as groups to ^{13}C*(8.9 + 9.5) and ^{13}N*(9.2): see (1981AJ01).
Observed α groups at E_{t} = 2.6 MeV are displayed in 13.22 (in PDF or PS) of (1976AJ04).
See (1987OS1E; theor.).
At E_{p} = 43.7 MeV ^{3}He groups have been observed to eleven states of ^{13}C: see 13.17 (in PDF or PS) in (1981AJ01).
At E_{α} = 42 MeV the angular distribution to ^{13}C_{g.s.} has been measured: see (1981AJ01). See also (1988SH1E; theor.).
Angular distributions have been measured for E_{n} to 18.8 MeV for α_{0}, α_{1}, α_{2+3}: see (1981AJ01). See also (1987MA1C; astrophysics).
At E_{α} = 42 MeV the angular distributions involving ^{13}C_{g.s.} have been measured: see (1981AJ01).
Angular distributions are reported at E(^{16}O) = 20.0 to 28.3 MeV to ^{13}C*(0, 3.09, 3.85) (1988WE17). See also (1989VO1D).
Angular distributions have been measured in both reactions at E_{d} = 13.6 MeV involving ^{13}C_{g.s.}: see (1986AJ01).
At E_{d} = 13.6 MeV an angular distribution has been reported by (1986GO26).
