(See Energy Level Diagrams for 13N)
Model calculations: (1955LA1A, 1957HU1C, 1959BA1D, 1960PH1A, 1960TA1C, 1961KU17, 1961KU1C, 1961NE1B, 1962IN02, 1962TA1E, 1963BA43, 1963BO1G, 1963SE19, 1963TR02, 1964AM1D, 1964BO1K, 1964ST1B, 1965BO1N, 1965MA1T, 1965ME1C, 1965WE1D, 1966EL08, 1966HA18, 1966NO1B, 1967BR1Q, 1967FA1A, 1967HU1C, 1967KU1E, 1967NE1D, 1967PO1J, 1967WA1C, 1968FI1F, 1968GO01, 1968HO1H, 1969VA1C, 1969ZU1B).
Measured values of the half-life are displayed in Table 13.22 (in PDF or PS). The positon spectrum shows no deviation from the allowed shape: it is concluded that the Fierz coefficient in the Fermi interaction is < 11% (1957DA08, 1958DA09, 1968DA1J). log ft = 3.664 based on Qm and τ1/2 = 9.961 min. The positon polarization has been studied by (1957BO65, 1957HA27). The results indicate that the positons are completely polarized and hence that Fermi transitions as well as GT transitions exhibit the maximum effect of parity non-conservation. See also (1959AJ76) and (1965GA1D, 1966MI1F, 1967AM1H, 1969LE1D, 1969SU15).
Observed resonances in the yields of proton groups and γ-rays for E(3He) = 1.2 to 12 MeV are displayed in Table 13.23 (in PDF or PS) (1956SC01, 1964KU09, 1966PA10). For polarization measurements see (1965SI05, 1967SI05) and (1966MI1E). See also 12C in (1968AJ02).
Excitation functions for the ground state group have been measured for E(3He) = 3.5 to 10 MeV: a resonance reported at E(3He) ≈ 5.8 MeV (1965PA10). See also (1965BR42, 1967HA20). See also 11C in (1968AJ02).
The excitation function for α-particles to 9B(0), measured for E(3He) = 2 to 10 MeV, indicates a strong resonance at E(3He) = 5.8 MeV (13N* = 26.1), Γ ≈ 1 MeV. This resonance does not appear in the excitation function for alphas to 9B*(2.3) measured over the same energy range. Minor structure is observed in both excitation functions approximately 2 MeV (1965PA05). See also 9B in (1966LA04) and (1968TA1M).
Ground state angular distributions have been measured for E(3He) = 2.0 to 5.3 MeV (1966DI04) and 4.7, 6.1 and 6.5 MeV (1969HO1F). Angular distributions at the latter energies of the neutrons corresponding to 13N*(3.51, 7.39, 9.52, 10.36, 11.87) indicate, respectively, L = (0, 2), (2, 4), (0, 2), (2, 4), (0, 2), in agreement with the Jπ assignments in Table 13.19 (in PDF or PS) (1969HO1F). Work at E(3He) = 1.2 to 2.0 MeV has shown tht previously reported states at Ex = 5.51 and 6.10 MeV in the 11B(3He, p)13C reaction are instead due to the proton decay to 12C(0) of 13N states at Ex = 9.52 ± 0.02 and 10.35 ± 0.02 MeV (1966CH18).
In a study with E(3He) = 7.0 to 13.5 MeV, neutron groups have been observed to T = 3/2 states at Ex = 15.068 ± 0.008 MeV (Γ < 15 keV), 18.44 ± 0.04 MeV and 18.98 ± 0.02 MeV (Γ = 40 ± 20 keV). Jπ (determined by DWBA) for 13N*(15.07) is 3/2- (1969AD02). The proton and γ-decay widths of 13N*(15.07) are displayed in Table 13.8 (in PDF or PS) where they are compared with the corresponding quantities for 13C*(15.11) (1968CO27, 1969AD01). Comparison of the reduced widths for the particle decays to 12C(0) and 12C*(4.4) show that the form of the isospin impurity in the 15.1 MeV, T = 3/2, states depend on TZ (1969AD01). See also (1964BR13, 1967TI1B, 1969MC1C).
Resonances for capture radiation displayed in Table 13.24 (in PDF or PS). [See also Table 13.17 (in PDF or PS) for a summary of the total radiation widths of low-lying levels of 13C - 13N.] No resonance is observed at Ep = 1.73 MeV, corresponding to 13N*(3.56) (1951SE67, 1963YO06).
No capture radiation is observed for Ex = 5 to 10.4 MeV: the upper limits to the (p, γ0) cross sections are 2 mb/sr at the known (p, p) resonances (1962PA07). At Ep = 14.2 MeV, capture radiation from the first T = 3/2 state at Ex = 15.07 MeV is observed. ΓpΓγ/Γ = 5.5 ± 0.8 eV for the ground state transition which, combined with Γp/Γ = 0.20 ± 0.025 from (1969AD01), yields Γγ = 27 ± 5 eV. The amplitude ratio of E2/M1 = -0.095 ± 0.07. For the transitions to 13N*(2.37) and 13N*(3.51+3.56), Γγ < 4.5 and 23 ± 5 eV, respectively. The angular distributions of the γ-rays determine J = 3/2 for 13N*(15.07) (1968DI04). No clear structure is observed in the ground state capture cross section for Ep = 14 to 19.5 MeV (1962WA31). Resonances reported by (1963FI07) in the yields of γ0 and γ2 are displayed in Table 13.22 (in PDF or PS). See also (1964TA05).
In the range Ep = 1.2 to 2.5 MeV, reaction (b) is observed, involving a γ-transition to the 2.37 MeV state. p-wave resonant capture at Ep = 1.70 MeV, with Γγ = 0.04 eV, interferes with direct p-wave capture (1954WO09). See also (1959DE28, 1959SU55, 1963CA09, 1964AL1J, 1965FA1E, 1965MA1H, 1966ED1A, 1968TH1K).
The cross section for this reaction has been measured from threshold to Ep = 50 MeV. Resonant structure is observed corresponding to Ex = 21, 24 and, possibly, ≈ 27 MeV (1968RI01). See also (1963VA1C, 1966SP09) and 12N in (1968AJ02).
Yield curves for elastic protons, protons inelastically scattered to 12C*(4.4, 7.7, 9.6, 12.7, 15.1), and for γ-rays from 12C*(12.7) and (15.1) have been studied at many energies up to Ep = 48.5 MeV: see Table 13.25 (in PDF or PS) for a display of the characteristics of the observed structure.
Total reaction cross section measurements have been made at Ep = 10 - 19 MeV (1968DI1D), 16.4 (1965PO07), 16.2 to 28 (1965MA26), 20 and 42 (1964GI05), 24.5 to 46.1 (1967MC1E), 28 (1964MA59), 34 (1959GO90), 45 (1967CA1K), 60 (1969ME08), 61 (1960ME16), 142 (1961TA06), 180 MeV (1961JO17) and 1 GeV (1967IG1A). Non-elastic cross sections have been measured at Ep = 9.9 and 10.2 MeV (1962IG1A, 1963WI12) and at 77, 95, 113 and 133 MeV (1962GO02).
A summary showing the energies at which polarization measurements have been made is presented as Table 13.26 (in PDF or PS). Reviews of the experimental evidence are given by (1959PH37, 1962RO14, 1966DA1B, 1966RO1R, 1966RO1B). See also (1959AJ76) and (1966KI1D).
The polarization and asymmetry in the elastic scattering of 32.9 MeV protons are equal to within ≈ 1%: therefore no violation of time-reversal invariance is observed in that part of the nuclear force which flips the spin of the proton (1968GR1K, 1969MA2D).
The following is a list of recent theoretical papers bearing on these reactions: (1955DE50, 1958BE1B, 1959BA24, 1959KE1A, 1959PU1A, 1959RI1A, 1959WI1C, 1960NI02, 1960SA1E, 1960SA1G, 1961SA1B, 1962MA1M, 1962NO04, 1962NO03, 1962NO1D, 1962RO1F, 1962VO04, 1963BA43, 1963HO1D, 1963LO1A, 1963LU1C, 1963RO1G, 1963SC1C, 1964CR1B, 1964GR1E, 1964IY1A, 1964TA1E, 1964VE1A, 1965BA1M, 1965BE1K, 1965CL1E, 1965FA1E, 1965HA28, 1965PE1F, 1965SA1H, 1966BA2N, 1967BA1C, 1967MC1H, 1967SA1C, 1967TA1B, 1967WO1E, 1968BA1K, 1968CH35, 1968FA1H, 1968KO26, 1968TA1U, 1968TI1B, 1969HA2C, 1969KO1J, 1969PA1H, 1969TA1D).
See also 12C in (1968AJ02).
The yield has been measured for Ep = 18 to 19.8 MeV: no structure is observed (1962WA31). Polarization measurements are reported by (1960CO05, 1967CH15, 1968IN02, 1969IN1C). See also 11C in (1968AJ02) and (1969BO1J, 1969ED02, 1969KO1P).
Yield curves for α0 have been measured over the 14.2 MeV resonance, corresponding to the first T = 3/2 state at Ex = 15.07 MeV, and from Ep = 17 to 20 MeV. The yield for the α1 group has been determined for Ep = 17 to 21.5 MeV. Parameters of observed resonances are displayed in Table 13.25 (in PDF or PS) (1969LE18). See also (1963VA1C, 1964BA29, 1966BA35, 1966RE1D, 1968TE1C) and 9B in (1966LA04).
In the range Ed = 2.8 to 3.7 MeV, a single neutron threshold is observed at Ed = 3.09 ± 0.02 MeV, corresponding to 13N* = 2.36 (5) ± 0.02 MeV (1955MA76).
At Ed = 4.7 to 5.5 MeV, broad proton groups are reported from the sequential decay 12C + d → 14N* → 13N* + n → 12C + n + p via 13N*(3.51, 3.56) (1963PI04). The proximity scattering associated with this process is charaterized by a mean lifetime for the intermediate state of 0.7 × 10-20 sec (1965LA08, 1965LA1F, 1966LA18). See also (1968BO02, 1969SA1K).
See also (1959AJ76), (1960MA21, 1961KE1C, 1961LE1E, 1961YA05, 1961YN02, 1963KN04, 1964CA1F, 1965GA1G, 1965JO09, 1965SI13, 1966HO1D, 1967OG1A) and (1961HO1D, 1963SM05, 1963TR1A, 1964SH1C, 1965MA1K, 1966ST1L, 1968HU1G).
Angular distributions of deuterons to 13N(0) have been measured at E(3He) = 6.0, 8.8, 9.4 and 10.1 MeV (1960HI07; d0), at 13.9 MeV (1960PR12; d0), at 16, 17 and 18 MeV (1969FO02; d0, d1, d2+3), at 19 MeV (1969FO02; d4, d5, d6, d7), at 21.6 and 24.7 MeV (1960WE04; d0, d1, d2+3), and at 29 MeV (1962GA17; d0, d1, d2+3). See also (1952FR1A, 1961YN02, 1966EC1B, 1966HA1Q, 1967HA21, 1967HO14, 1969FO02). For reaction (b) see (1969FO02).
Angular distributions have been measured at Eα = 43 MeV (1967DE1K; t0), 46 MeV (1969FO1C; t2 + t3) and at 56 MeV (1968GA1C, 1969GA11; t0). At Eα = 56 MeV a detailed comparison is made with the 3He distribution from the mirror reaction 12C(α, 3He)13C (1969GA11). See also (1961YN02, 1963TR1A, 1964SH1C).
Angular distributions of ground state neutrons have been measured at Ep = 3.1 to 5.3 MeV (1961AL07), 3.39 to 12.86 MeV (1961DA09), 5.0 to 13.3 MeV (1961WO03) and 18.5 MeV (1964AN1B). See also (1962PA07, 1964ST1C, 1965VA23) and (1959BL1B, 1963EL1B, 1964CA1F, 1964SA1D, 1966PA1H).
Two thresholds are observed at Ep = 3.235 and 6.965 MeV (± 10 keV), corresponding to 13N(0) and 13N*(3.464) (1966RI09). The neutron group corresponding to 13N*(2.3) is very weak compared to the groups to 13N(0) and 13N*(3.5) at the energies studied (1961DA09). See also (1959AJ76), (1959BO14, 1966UN1A, 1968AT1A, 1968LI1G, 1968RI1Q, 1968WO1D, 1969PA1J) and 14N.
At E(3He) = 39.6 MeV, angular distributions have been obtained for the tritons corresponding to the ground state of 13N and to the excited states at 2.37, 3.53 ± 0.03 [u], 6.38, 7.17, 7.39, 8.92 ± 0.04, 11.85 ± 0.04 and 15.07 MeV. States at Ex = 9.5, 10.78 ± 0.04 and 15.98 ± 0.05 MeV were also populated, the first of these weakly. The transitions to 13N*(7.39, 8.92, 11.85, 15.07) are L = 2 [Jπ = 5/2-, 1/2-, 3/2-, 3/2-, respectively] (1968BA1E, 1969BA06). See also (1966EC1B).
Angular distributions have been determined at Ep = 14 MeV (1969CU1D; d0), 18.5 MeV (1961BE12; d0, d1, d2+3), 30.3 MeV (1967KO08; d0, d2, and the deuterons to 13N*(7.38, 8.93, 11.80)), 45 MeV (1966MA2B; d0, d1, d2+3, and the deuterons to 13N*(7.4 ± 0.1, 11.8 ± 0.2)) and 155.6 MeV (1966BA44; d0, d2+3, and the deuterons to 13N*(7.4, 9.0, 11.9)). See also (1964EL1B, 1967OG1A, 1969DO08, 1969TO1A). For reaction (b), see (1962BA1A). See also 14N.
Angular distributions of the tritons to 13N*(0, 3.51, 7.38, 8.93 + 9.48, 11.8) have been obtained at Ed = 52 MeV and analyzed by DWBA. The spectroscopic factors for the 13N states [and the mirror states reached in the 14N(d, 3He)13C reaction] are in good agreement with theory and are additional evidence for the Jπ assignments of 1/2-, 3/2-, 5/2-, 1/2-, 3/2- and 3/2- to these states (1968HI01). Comparisons of (d, t) and (d, 3He) angular distributions are also reported by (1966DE1C, 1968GA13).
Alpha-particle groups have been observed to the ground state of 13N and to excited states at 2.358 ± 0.010, 3.471 ± 0.015 MeV (1960TA12), 6.38, 6.91, 7.166 ± 0.008 and 7.388 ± 0.008 MeV (1962CL12). See also (1963GA03). Angular distributions have been studied at E(3He) = 4.5, 5.5 and 7.0 MeV (1967KN1B; α0, α1, α2+3), 13.9 MeV (1968LU03; α0, α1, α2+3, α4, α6+7), 17.4 to 36.6 MeV (1965AR07; α0, α1, α2+3, α5+6 and the alphas to 13N*(11.4)), 29 MeV (1962SE13; α0), and at 40 - 45 MeV (1967BA2G). For reaction (b) see (1967DE1T). See also (1964EL1B, 1965BO1N, 1966BO1U, 1967BE22, 1967OG1A, 1968ZE1B, 1969DO08).
As expected from isospin conservation the angular distributions (at E(14N) = 78 MeV) of 13N and 13C are symmetric about 90° (1969VO01).
At Ep = 43.7 MeV, angular distributions have been obtained for the tritons corresponding to the ground state of 13N and the excited states at 3.51 (3/2-), 6.38 ± 0.03 (5/2+), 7.38 (5/2-), 8.93 ± 0.05 (1/2-), 10.78 ± 0.06 (1/2-), 11.88 ± 0.04 (3/2-) and 15.07 (3/2-; T = 3/2) MeV states [Jπ values in parentheses, as determined by DWBA analyses using intermediate-coupling wave functions to obtain the twwo-nucleon structure factors] (1968FL03). Detailed comparisons have been made with the (p, 3He) reaction to the mirror states in 13C (1968FL02, 1968FL03). See also (1966CE02, 1966CE05) and (1969VA1C).
Angular distributions of the ground state α-particles have been measured at Ep = 7.9 to 10.2 MeV (1964DA02), 13.5 to 18.1 MeV (1961MA15) and 38 MeV (1969GA03, 1967AC01). See also (1962VA1A, 1964CE1D), (1957CH1A, 1961WI1F, 1964HO1D) and 17F in (1971AJ02). For reaction (b), see (1967CH04).