A=11B (1975AJ02)

Angular distributions of the protons have been reported at E(⁶Li) = 2.0 MeV (1971PO1D; unpublished: E_x ≤ 8.0 MeV) and 2.4 to 9.0 MeV (1966KI09: E_x < 9.3 MeV). For γ-spectra see (1962BE24, 1969TH01) and Table 11.4 (in PDF or PS). τ_m, measured in this reaction and in reactions 7, 8 and 29 are shown in Table 11.5 (in PDF or PS) (1969TH01).

2. ⁷Li(α, γ)¹¹B Q_m = 8.666

Resonances for capture radiation are displayed in Table 11.6 (in PDF or PS) (1951BE13, 1954HE22, 1967PA19). Angular distributions, branching ratios and correlations have been studied by (1959JO25, 1962GR07): they determine J^π = 5/2^-, 7/2^-, 5/2^- or (3/2⁺), 7/2⁺ and 5/2⁺, respectively for ¹¹B*(4.45, 6.74, 8.92, 9.19, 9.28): see (1968AJ02) for a more complete discussion and Tables 11.4 (in PDF or PS) and 11.6 (in PDF or PS). See also (1969OM1A).

3. ⁷Li(α, n)¹⁰B Q_m = -2.790 E_b = 8.666

Cross section measurements have recently been carried out by (1968MA07) for E_α = 4.43 to 5.12 MeV (n₀) and by (1972VA02) for E_α = 4.5 to 8.0 MeV (n₀) and 5.7 to 8.0 MeV (n₁). Results from these and previous measurements are displayed in Table 11.7 (in PDF or PS) (1957BI84, 1959GI47, 1963ME08). See also (1968DA1H).

4. ⁷Li(α, p)¹⁰Be Q_m = -2.5638 E_b = 8.666

See ¹⁰Be in (1974AJ01).

5. ⁷Li(α, t)⁸Be Q_m = -2.5586 E_b = 8.666

Excitation functions have been measured for E_α = 14 to 25 MeV (t₀) and 18 to 25 MeV (t₁): they are essentially smooth (1972VA34). See also ⁸Be in (1974AJ01) and (1974KA32; theor.).

6. ⁷Li(α, α)⁷Li E_b = 8.666

The elastic scattering has been studied for E_α = 1.6 to 12 MeV (1966CU02), 2.5 to 4.5 MeV (1972BO07), 8.6 to 12.5 MeV and 17.0 to 22.5 MeV (1973KE13) and 12.0 to 18.0 MeV (1970BI1B, 1971BI12). The inelastic scattering, leading to ⁷Li*(0.48), has been studied at E_α = 1.6 to 12 MeV (1966CU02), 1.6 to 3.2 MeV (1967PA19), 2.5 to 4.5 MeV (1972BO07), 5.8 to 6.7 MeV (1975BA06) and 17.0 to 22.5 MeV (1973KE13). See also (1968AJ02) for earlier references.

Observed resonances are displayed in Tables 11.8 (in PDF or PS) and 11.9 (in PDF or PS) (1966CU02, 1967PA19). A weak structure at E_α ≈ 12.7 MeV and broad structures at E_α ≈ 12 to 15 MeV are reported by (1970BI1B, 1971BI12): it is not clear whether these correspond to states in ¹¹B. (1973KE13) suggest that the deviations from smooth behavior in the excitation functions are due to the exchange of a triton cluster between two α-particles. See also ⁷Li in (1974AJ01).

7. ⁷Li(⁶Li, d)¹¹B Q_m = 7.192

Angular distributions of deuterons have been measured at E(⁷Li) = 3.3 MeV (1967GA06: d₀ → d₃) and 3.78 to 5.95 MeV (1967KI03: d₀ → d₃, d₄₊₅, d₆). For γ-spectra see (1962BE24, 1969TH01) and Table 11.4 (in PDF or PS). For τ_m see Table 11.5 (in PDF or PS) (1969TH01). See also ¹³C in (1976AJ04).

8. ⁷Li(⁷Li, t)¹¹B Q_m = 6.199

Angular distributions have been measured at E(⁷Li) = 2.10 to 5.75 MeV (1969CA1A: t₀ → t₃). For τ_m see Table 11.5 (in PDF or PS) (1969TH01). At E(⁷Li) = 79.6 MeV transitions are observed to several ¹¹B states. ¹¹B_g.s. is particularly strongly populated: 23 μb/sr, at 7.4° (1974CE06). See also (1974CE1A).

9. ⁹Be(d, γ)¹¹B Q_m = 15.8167

Radiative transitions have been observed to ¹¹B*(0, 2.12, 4.45 + 5.02) at E_d = 0.5 to 1.4 MeV (1966ZI01) and 0.56 to 3.56 MeV (1970BA1R, 1971BA72). The 90° γ₀ differential cross section has been measured for E_d = 0.5 to 5.5 MeV (1963SU09, 1966SU05, 1966SU1C) and 2.9 to 11.9 MeV (1974DE01, 1974DE39). The behavior of the γ₀, γ₁ and γ₂₊₃ total cross sections and of the angular distributions of these γ-rays indicate two resonances at E_d = 1.98 ± 0.05 and 3.12 ± 0.05 MeV with Γ_lab = 225 ± 50 and 320 ± 100 keV, corresponding to ¹¹B*(17.43, 18.37). The higher resonance was not observable in the γ₂ + γ₃ cross section which was not measured beyond E_d = 2.5 MeV. The maximum γ₀ cross section observed is 10.1 ± 3.5 μb at E_d ≈ 0.96 MeV (1971BA72). (1974DE39) observe resonant behavior in the 90° γ₀ cross section at E_d ≈ 3.4 and 9.65 MeV (¹¹B*(18.6, 23.7)) in addition to a wide structure at 4.7 MeV (¹¹B*(19.7)). The angular distributions of γ₀ from ¹¹B*(18.6, 23.7) are typical of E1 transitions. The (d, γ₀) reaction appears to proceed via excitation of the T = 1/2 component of the giant dipole resonance in ¹¹B.

10. ⁹Be(d, n)¹⁰B Q_m = 4.3607 E_b = 15.8167

The cross section follows the Gamow function for E_d = 70 to 110 keV (1955RA14). The fast neutron and γ-yield rise smoothly to E_d = 1.8 MeV except for a possible "resonance" at E_d ≈ 0.94 MeV. The fast neutron yield then remains approximately constant to 3 MeV: see (1968AJ02) for references. The excitation functions for n₀ → n₄, and n to ¹⁰B*(5.1, 6.57) have been measured for E_d = 14 to 16 MeV: no strong fluctuations are observed (1973PA14). Polarization measurements have been reported at E_d = 0.9 to 2.5 MeV (1970MI04: n₀ → n₄), 3.0 to 5.5 MeV (1974TH02: n₀ → n₅ and n to ¹⁰B*(5.1, 6.6)) and 3.0 and 3.5 MeV (1970SP1A, 1971SP1C: n₀ → n₄). For papers dealing with applications see (1971DA21, 1971EL1B, 1972LU1B, 1973AU1G, 1973WE1T, 1973WE19). See also (1972DA34, 1973SZ07 ), (1970MI1G; theor.) and ¹⁰B in (1974AJ01).

11. (a) ⁹Be(d, p)¹⁰Be Q_m = 4.5873 E_b = 15.8167
(b) ⁹Be(d, α)⁷Li Q_m = 7.1511
(c) ⁹Be(d, t)⁸Be Q_m = 4.5925

Recently measurements of proton yields have been carried out by (1974AN01: 0.3 to 0.9 MeV; p₀, p₁), (1974FR02: 0.6 to 2.7 MeV (p₀), 1.0 to 2.7 MeV (p₁)), (1972AR31: 0.75 to 2.25 MeV; p₀), (1974BO42: 0.9 to 2.5 MeV; p₀, p₁), (1973SA1Q: 0.9 to 3.1 MeV; p₀, p₁) and (1970PO03: 4.5 to 6.0 MeV; p₀, p₁). From these and previous measurements it appears that the p₀ and p₁ yields show a resonance at E_d = 750 ± 15 keV [¹¹B*(16.43)], Γ ≈ 40 keV (1974AN01) and the p₁ yield a resonance at 1.85 MeV [¹¹B*(17.33)], Γ_c.m. ≈ 1.0 MeV (1973SA1Q). [The latter is also reported in the yield of 3.37 MeV γ-rays by (1957MC35).] Broad maxima have also been reported at E_d ≈ 0.9 MeV, (1.3) and 2.1 MeV by (1952CA19: p₀) [see also (1972AR31)] and at 1.3 MeV by (1957MC35: 3.37 MeV γ-ray). (1974FR02) report a broad resonance at E_d = 1.8 MeV and a sharp resonance at 2.3 MeV, in the p₁ yield. See also (1968BE1E). Polarization of the protons has been studied at many energies in the range E_d = 1 to 21 MeV: see (1968AJ02) for the earlier work and (1968YU01: 7.0 MeV; p₀), (1969CU10: 10.0 MeV; p₀), (1970FI07: 10 and 12 MeV; p₀, p₁), (1971GR20: 11.8 MeV; p₀), (1971BR44: 12 MeV; p₀), (1972BU26: 12.0 MeV; p₀, p₁), (1968BA19, 1973JO10: 12.3 MeV; p₀, p₁). See also (1967SA06, 1972FI1E, 1973FI1C). See also ¹⁰Be in (1974AJ01).

The yields of α-particles, both α₀ and α₁, (reaction (b)) have been measured at E_d = 0.3 to 0.9 MeV (1974AN01), 0.5 to 2.3 MeV (1962BI11), 0.6 to 2.0 MeV (1974FR02), 0.9 to 2.2 MeV (1971SA27) and 8 to 12.4 MeV (1966DO1A; also α₂ for E_d = 9 to 12.4 MeV). (1974AN01) report a weak indication of the 0.75 MeV resonance, observed in the proton yield, in the α₀ yield. (1962BI11) find no clear indication of resonance structure. See also (1968BE1E, 1973SZ07) and ⁷Li in (1974AJ01).

The cross section for reaction (c) has been measured for E_d = 0.15 to 19 MeV: see (1968AJ02) for the earlier references and (1974AN01: 0.3 to 0.9 MeV; t₀), (1974FR02: 0.6 to 2.0 MeV; t₀), (1974BO42: 0.9 to 2.5 MeV; t₀) and (1973SA1Q: 0.9 to 3.1 MeV; t₀). There is no clear evidence of resonance structure: see, however, (1955JU10, 1955JU1B, 1958JU38). See also ⁸Be in (1974AJ01).

See also (1973BI1G), (1971EL1B: applied) and (1971KO41; theor.).

12. ⁹Be(d, d)⁹Be E_b = 15.8167

Excitation functions for elastically scattered deuterons have been measured for E_d = 0.4 to 1.8 MeV (1963RE16), 1.0 to 2.2 MeV (1972LO05), 1.0 to 2.5 MeV (1968MA1H), 4.5 to 6.0 MeV (1970PO03) and 5.0 to 7.0 MeV (1971DJ02). Polarization measurements involving the d₀ group have been reported at E_d = 6.3 MeV (1971DJ02), 11.8 MeV (1971GR20) and 12.6 MeV (1971ZA04). See also (1970VE06, 1971SP1C) and ⁹Be in (1974AJ01).

13. ⁹Be(t, n)¹¹B Q_m = 9.5591

Angular distributions are reported at E_t = 1.1 MeV (1970MAZE; unpublished).

14. ⁹Be(³He, p)¹¹B Q_m = 10.3229

Proton groups have been observed to a number of ¹¹B states: see Table 11.10 (in PDF or PS) (1959HI69, 1966BR18). See also (1970CA28). Angular distributions of many of these proton groups have been studied at E(³He) = 1.0 to 10.2 MeV: see (1968AJ02) for references and (1973SU07: E(³He) = 0.82 and 1.10 MeV). L assignments derived from the higher energy work (1960HI08) are also shown in Table 11.10 (in PDF or PS). Gamma ray branching ratios and multipolarities for ¹¹B levels up to E_x = 9.19 MeV have been extensively studied by (1958FE70, 1961DO03, 1964AL22, 1965OL03): see Table 11.4 (in PDF or PS) and the discussion in (1968AJ02). Lifetime measurements are shown in Table 11.5 (in PDF or PS) (1969BEYX; abstract). See also (1970OG1A) and (1970LK1A; theor.).

15. ⁹Be(α, d)¹¹B Q_m = -8.031

Angular distributions have been measured at E_α = 27.0 (1975PU01: d₀ → d₆) and 28.3 MeV (1965KA14: d₀ → d₃). The predominant L-transfer are L = 0, 2; 0 and 0, respectively for ¹¹B*(0, 2.12, 5.02). The angular distribution for ¹¹B*(4.45) is flat (1975PU01). See also (1970OG1A) and (1971BU1K; theor.).

16. (a) ⁹Be(⁶Li, α)¹¹B Q_m = 14.343
(b) ⁹Be(⁶Li, 2α)⁷Li Q_m = 5.677
(c) ⁹Be(⁶Li, αp)¹⁰Be Q_m = 3.114
(d) ⁹Be(⁶Li, αt)⁸Be Q_m = 3.119

Angular distributions have been determined for seven α-groups at E(⁶Li) = 3 to 4 MeV: see (1968AJ02). Angular distributions have also been obtained at E(⁶Li) = 24 MeV to ¹¹B*(0, 2.12) and to a number of unresolved levels with E_x ≤ 13.2 MeV (1967CH34, 1968DA20). See also (1970OG1A).

The breakup reactions (reactions (b), (c) and (d)) have been studied at E(⁶Li) = 3.5 MeV by (1968JA08): reaction (b) goes mainly via a sequential process involving ¹¹B*(10.3, 11.4, 12.6, 13.16, 13.5). The results for reaction (c) are not conclusive. ¹¹B*(12.6, 13.16) may possibly contribute to reaction (d) (1968JA08).

17. (a) ⁹Be(⁷Li, αn)¹¹B Q_m = 7.092
(b) ⁹Be(⁹Be, ⁷Li)¹¹B Q_m = -0.880

For reaction (a) see (1964CA18). For reaction (b) see (1970LK1A; theor.).

18. ¹⁰Be(p, γ)¹¹B Q_m = 11.229

The yield of ground state γ-rays has been measured at 90° for E_p = 0.6 to 6.3 MeV. Observed resonances are displayed in Table 11.11 (in PDF or PS). The anomaly observed at E_p = 1.05 MeV may not correspond to a state in ¹¹B: it occurs at the threshold for ¹⁰B*(0.72) + n. The other four resonances correspond to states in ¹¹B whose energies match well with those of the first four states in ¹¹Be: T = 3/2. Several known T = 1/2 states in ¹¹B are not observed in this reaction: see Table 11.3 (in PDF or PS) (1970GO04, 1973GO09).

19. ¹⁰B(n, γ)¹¹B Q_m = 11.4560
Q₀ = 11454.7 ± 1 keV (1967RA24);
Q₀ = 11453 ± 2 keV (1967TH05).

The thermal capture cross section is 0.5 ± 0.2 b (1973MU14). For a listing of the observed capture γ-rays see Table 11.12 (in PDF or PS) (1967TH05). The τ_m for ¹¹B*(6.74) is 10⁺¹²_-8 fsec (1969WE07). See also (1973AR1M, 1974AR1K, 1974ST1C) and (1968FOZY; astrophys.).

20. ¹⁰B(n, n)¹⁰B E_b = 11.4560

The "free" neutron scattering cross section, (σ-bar)_s = 2.23 ± 0.06 b. The coherent scattering amplitude (bound) is a = +1.4 ± 0.5 fm (1973MU14). See also (1969BA1P). The total scattering cross section is constant at 2.23 ± 0.06 b for E_n = 0.7 to 10 keV and then rises to 2.97 b at E_n = 127 keV (1970AS10).

Total cross section measurements in the range E_n = 10 to 500 keV confirm the broad maximum near E_n = 0.23 MeV, originally suggested by (1951BO45) and also observed in the (n, α) cross section (1966MO09). At higher energies the total cross section shows broad maxima at E_n = 1.9 and 2.8 MeV (1951BO45) and at 4.3 MeV (1961FO07): see Table 11.13 (in PDF or PS). In the range E_n = 5.5 to 16 MeV σ_tot is constant at 1.5 b (1961FO07).

Polarization measurements (0.075 to 2.2 MeV and 2.63 MeV) and measurements of differential cross sections (0.075 to 4.4 MeV) by (1971LA10, 1973CO05, 1973HA2G, 1973HA64) have been analyzed using R-matrix calculations: the results are shown in Table 11.14 (in PDF or PS). They are consistent with results from ¹⁰B(n, n'γ) and ⁷Li(α, n).

Elastic scattering differential cross sections are also reported at E_n = 7.02 and 7.55 MeV (1969HO1G) and at 9.72 MeV (1970CO12). See also (1969MA39, 1970PO1E), (1967IR1A, 1972LA1F) and (1966AG1A, 1967BE1F; theor.).

21. ¹⁰B(n, n')¹⁰B* E_b = 11.4560

The yield of 0.7 MeV γ-rays has been studied from threshold to E_n = 5.2 MeV: observed resonances are displayed in Table 11.13 (in PDF or PS) (1960DA08). See also (1970NE03). Inelastic scattering cross sections for formation of various ¹⁰B states have been measured by (1970NE03: E_n = 1.45 to 4.90 MeV, and 14.8 MeV), (1969HO1G: E_n = 7.02 and 7.55 MeV) and (1970CO12: E_n = 9.72 MeV). See also ¹⁰B in (1974AJ01) and (1969RO1F).

22. ¹⁰B(n, p)¹⁰Be Q_m = 0.2266 E_b = 11.4560

The thermal cross section is < 0.2 b (1973MU14). See also ⁹Be in (1974AJ01) and (1970NE03).

23. ¹⁰B(n, d)⁹Be Q_m = -4.3607 E_b = 11.4560

See ⁹Be in (1974AJ01).

24. (a) ¹⁰B(n, t)⁸Be Q_m = 0.2318 E_b = 11.4560
(b) ¹⁰B(n, t)⁴He⁴He Q_m = 0.3237

The cross section for reaction (b) has been measured for E_n = 1.4 to 8.2 MeV by (1961DA16). Fluctuations are observed at some of the resonant energies in the ¹⁰B(n, α) reaction: see Table 11.13 (in PDF or PS). See also (1968ST1D) and (1969AN25, 1971AN1M).

25. ¹⁰B(n, α)⁷Li Q_m = 2.790 E_b = 11.4560

The "recommended" value of the thermal isotropic absorption cross section is 3837 ± 9 b (1973MU14). See also (1970ME1F). The ground state branching for thermal neutrons is 6.308 ± 0.006% (1967DE15). See also (1968MA07), and (1968AJ02) for earlier references. The cross section for E_n = 10 eV to 200 keV is given by the expression

(1970SO1A).

The cross section for the (n, α₀) reaction has been calculated by (1968MA07) from that for the ⁷Li(α, n) reaction: E_n = 30 to 516 keV.

The α₁ cross section has been measured for E_n = 47 keV to 4.9 MeV and at 14.8 MeV (1970NE03): the cross section is substantially higher than that reported by (1961DA16). Observed resonances are displayed in Tables 11.13 (in PDF or PS) and 11.14 (in PDF or PS) (1961DA16).

Other recent measurements include those by (1969BO03) at E_n = 30 to 800 keV (relative cross sections for α₀ and α₁) and by (1969AN25) at 14.4 MeV (cross section for formation of α₀ + α₁, α₂). (1972HA04) have calculated differential cross sections for α₀ and α₁ based on R-matrix parameters derived from neutron elastic scattering, polarization measurements and (n, α) data. See also (1974HA1W, 1975HA1G; theor.). See also ⁷Li in (1974AJ01), (1968GI1D, 1968GU1B, 1968ST1D, 1970DE1H, 1972LA1F, 1975FR1B ), (1964FO1A; astrophys.) and (1968MO1D, 1968PA1E, 1973FA1M, 1973LI1E; applied).

26. ¹⁰B(p, π⁺)¹¹B Q_m = -128.895

Angular distributions for proton capture to ¹¹B*(0, 2.15 ± 0.10) have been measured at E_p = 185 MeV. The population of ¹¹B*(4.45 + 5.02) and of unresolved higher states is also observed but an attempt to observe T = 3/2 analogue states in ¹¹B and ¹¹N (the latter populated via (p, π^-)) was unsuccessful (1974DA27).

27. ¹⁰B(d, p)¹¹B Q_m = 9.2314

Proton groups reported by (1951VA1A, 1963EL12, 1961JA23, 1966BR18) are listed in Table 11.15 (in PDF or PS). Angular distributions have been studied at many energies in the range E_d = 0.17 to 28 MeV [see (1968AJ02) for a listing of the earlier references] and (1970HU1B: 0.35 MeV; p₀ → p₃, p₄₊₅, p₆, p₇), (1973CO18: 0.67 to 2.32 MeV; p₄₊₅), (1970PO03: 4.5 to 5.5 MeV; p₀ → p₃) and (1967GO27: 13.6 MeV; p₀). The lowest five levels are formed by l_n = 1 except for ¹¹B*(2.12) which appears to involve a spin-flip process. They are presumed to comprise the set 3/2^-, 1/2^-, 5/2^-, 3/2^-, 7/2^- expected as the lowest p⁷ levels (a/K ≈ 4.0). ¹¹B*(9.19, 9.28) [J^π = 7/2⁺ and 5/2⁺, respectively] show strong l = 0 stripping and are ascribed to capture of a 2s neutron by ¹⁰B: see (1968AJ02) for a listing of all the relevant references. The probability p_3/2 for transfer of a neutron with angular momentum 3/2 has been determined for the p₀ group using vector polarized deuterons with E_d = 10 and 12 MeV, and compared with shell model calculations of (1965CO25, 1967CO32), (1970FI07; and see also (1967SC29)).

Studies of pγ correlations are discussed in reaction 14 of (1968AJ02) and displayed in Table 11.4 (in PDF or PS) of this paper.

See also ¹²C, (1967CO30, 1967SP09, 1973BR24), (1973FO02) and (1969BO1F, 1969DO08, 1970DE35, 1970DO07, 1970DO13; theor.).

28. ¹⁰B(t, d)¹¹B Q_m = 5.1984

At E_d = 5.5 MeV, deuteron groups are observed to the ground state of ¹¹B and to states at E_x = 2.126, 4.449, 5.027, 6.769, 6.806 and 7.301 MeV (± 10 keV). All the angular distributions appear to be characteristic of l_n = 1 (1961BA10). See also ¹³C in (1976AJ04).

29. ¹⁰B(α, ³He)¹¹B Q_m = -9.1225

Angular distributions have been measured at E_α = 56 MeV for the ground state transitions in this, and in the analog (α, t) reactions: the average ratio of the (α, ³He) to the (α, t) differential cross sections is 1.2 ± 0.1 (1968GA1C, 1969GA11).

30. (a) ¹⁰B(⁶Li, ⁵Li)¹¹B Q_m = 5.79
(b) ¹⁰B(⁷Li, ⁶Li)¹¹B Q_m = 4.205

See (1969TH01) for reaction (a) and (1974KO1G) for reaction (b).

31. ¹⁰B(¹⁴N, ¹³N)¹¹B Q_m = 0.902

See (1968GA03) and (1968GO1K, 1970GO1B, 1970SC1G, 1973MC17, 1973OS03; theor.) and (1968AJ02).

32. ¹⁰B(¹⁵N, ¹⁴N)¹¹B Q_m = 0.622

Not reported.

33. ¹⁰B(¹⁶O, ¹⁵O)¹¹B Q_m = -4.213

See (1968OK06).

34. ¹⁰B(¹⁸O, ¹⁷O)¹¹B Q_m = 3.409

The angular distribution has been measured at E(¹⁸O) = 20 and 24 MeV (1971KN05). See also (1974SW04).

35. ¹⁰B(¹⁹F, ¹⁸F)¹¹B Q_m = 1.025

The angular distribution has been measured at E(¹⁹F) = 20 and 24 MeV (1971KN05). See also (1968GA03) and (1970GO1B; theor.).

36. ¹¹Be(β^-)¹¹B Q_m = 11.509

¹¹Be decays to ¹¹B*(0, 2.12, 5.02, 6.79, 7.98, 9.87): see Table 11.16 (in PDF or PS) for the parameters of the observed β and γ transitions (1971AL07). Delayed α-particles are also observed with a total I_α of 3.0%/decay. These α-particles are not observed to be in coincidence with 478 keV γ-rays [upper limit = 5% for E_α > 0.3 MeV], suggesting that they result from the decay of ¹¹B*(9.87) to ⁷Li_g.s. (1971AL07). The half-life of ¹¹Be is 13.81 ± 0.08 sec (1970AL21). See also (1968AJ02) and (1974AL11).

37. ¹¹B(γ, γ)¹¹B

Mean gamma widths of low-lying states obtained by resonance scattering and transmission studies are listed in Table 11.17 (in PDF or PS) (1958ME79, 1958RA14, 1959CO95, 1964BO22, 1965KE05, 1968CR07, 1973SA21, 1974LE1K). See also (1974WE1R) and (1968AJ02).

38. (a) ¹¹B(γ, n)¹⁰B Q_m = -11.4560
(b) ¹¹B(γ, p)¹⁰Be Q_m = -11.2294
(c) ¹¹B(γ, d)⁹Be Q_m = -15.8167
(d) ¹¹B(γ, t)⁴He+⁴He Q_m = -11.1323
(e) ¹¹B(γ, α)⁷Li Q_m = -8.666

The giant dipole resonance is shown to consist mainly of T = 1/2 states in the lower energy region and of T = 3/2 states in the higher energy region by observing the decay to states in ¹⁰B and ¹⁰Be (reactions (a) and (b)) (1971PA10). Absolute measurements of the ¹¹B(γ, all n) cross section from threshold to 28 MeV have been carried out by (1973HU09, 1973HU1D): the cross section exhibits a maximum at E_γ = 25.2 ± 0.1 MeV (σ ≈ 8 mb) in addition to some weaker structure. The integrated cross section from threshold to 27.6 MeV is 0.37 ± 0.04 in units of 60 NZ/A. The results are consistent with the photoabsorption cross section proceeding via T = 1/2 at lower energies (1973HU09). This is also the picture derived from the (γ, d₀) cross section (reaction (c)): it peaks at ≈ 19 MeV, lower than it would if T = 3/2 states were involved (1974DE01). See also (1968KA38, 1969MU10, 1971KA70, 1972SL1B) and (1970HA28).

The cross section for (γ, n) shows many peaks in the range E_γ = 12 to 28 MeV (1965HA19). (1969SO06, 1970SO03) report resonances at E_γ = 12.4, 13.1, 13.65, 14.75, 15.1, 15.5, 15.85, 16.2, 16.5, 16.9, 17.5, (20.2), 21.6, 23.2, (24.5), 25.5, 27.7 and 29.2 MeV in the (γ, p) cross section. [See (1970SO03) also for Γ_γ and J^π for the states below 18 MeV (mainly 5/2⁺), and for an evaluation of the structure reported by (1965HA19).] See also (1972BU1J, 1973SP02) and (1971DU11; theor.). For reactions (d) and (e) see (1959AJ76).

39. (a) ¹¹B(e, e)¹¹B
(b) ¹¹B(e, ep)¹⁰Be Q_m = -11.229

The charge-scattering radius is 1.55 fm (1959ME24). Magnetic elastic scattering at θ = 180° shows strong M3 effects: the derived ratio of static M3/M1, 2.9 ± 0.2 fm², suggesting a j - j coupling scheme for ¹¹B_g.s. (1966RA29). The quadrupole contribution to the elastic form factor is best accounted for by the undeformed shell model, Q = 3.72 ( ± 20%) fm², r(r.m.s.) = 2.42 fm (1966IS1A, 1966ST12). The excitation of ¹¹B*(2.1, 4.4, 5.0, 8.6, 8.9) has been studied by (1975KA02: E_e = 52 to 90 MeV). (1973FL1A) report the excitation of ¹¹B*(7.30, 9.27) at the same E_e. The giant resonance region, centered at ≈ 18 MeV, is characterized by a lack of prominent features except for a pronounced peak at E_x = 13.0 ± 0.1 MeV (mixed M1 - E2) and a broad transverse group at E_x = 15.5 MeV (1975KA02).

Ground state transition widths for various excited states are listed in Table 11.17 (in PDF or PS) (1962ED02, 1966KO08, 1966SP02, 1967SP02, 1975KA02). For reaction (b) see (1971VL01, 1972VL1A) and ¹⁰Be in (1974AJ01). See also (1968AJ02), (1971RI1E), (1968GO1J, 1972THZF), (1968JA1D, 1969VI02, 1973DO01, 1973GA19, 1973RO11, 1973SP02; theor.).

40. ¹¹B(n, n')¹¹B*

Angular distributions of neutrons have been measured at E_n = 7.55 MeV (1969HO1G: n₀ → n₂), 9.72 MeV (1970CO12: n₀ → n₃, n₄₊₅) and 14.1 MeV (1970AL08: n₀ → n₃, n₄₊₅, n₆). For branching ratios see Table 11.4 (in PDF or PS) (1972NI05). See also ¹²B, (1968AL1E, 1970PO1E) and (1968CA1A, 1969WA11, 1971MI12, 1971OT03, 1974BI07; theor.).

41. (a) ¹¹B(p, p')¹¹B*
(b) ¹¹B(p, 2p)¹⁰Be Q_m = -11.229

Observed proton groups are displayed in Table 11.18 (in PDF or PS) (1969SU03, 1971BR41, 1974KA15). Angular distributions have been measured at E_p = 12 to 21.5 MeV (1972TH1C), 30.3 MeV (1969KA15: p₀ → p₂), 100 MeV (1970HO07: p₀ → p₃), 155 MeV (1968GE04: p₀ → p₃, p₄₊₅) and 185 MeV (1969SU03: p₀ → p₂ and p to ¹¹B*(8.56, 8.92)). For an angular correlation experiment see (1970HU01). See also (1968AJ02), (1970TH1F, 1973CA1H), (1969WA11, 1971LO05, 1973KA04; theor.) and ¹²C. For reaction (b) see ¹⁰Be in (1974AJ01). The spectroscopic factors for the (t + ⁸Be) and (α + ⁷Li) cluster structures in ¹¹B [as determined from a study of the ¹¹B(p, α)⁸Be reaction] are ≈ 0.77 and ≈ 0.02, respectively (1972DE01, 1972DE02).

42. ¹¹B(d, d)¹¹B

The elastic scattering has been studied at E_d = 5.5 MeV (1971HIZF) and 11.8 MeV (1967FI07). See also (1968VE11, 1968VE1C, 1970VE06, 1971TAZN) and (1969VE09, 1970EL16; theor.).

43. ¹¹B(t, t)¹¹B

The elastic scattering has been studied at E_t = 1.8 and 2.1 MeV (1969HE08, 1969SI12).

44. (a) ¹¹B(³He, ³He)¹¹B
(b) ¹¹B(³He, ⁶He)⁸Be Q_m = 4.570

The elastic scattering has been studied at E(³He) = 8, 10, 12, 15 and 18 MeV (1969MI15, 1969PA11), 14 MeV (1970NU02) and 18.3, 20.6 and 27.2 MeV (1972BU30), and 74 MeV (1974AS06: also ¹¹B*(4.45)). A coupled channel analysis of the 74 MeV results suggests a quadrupole deformation β₂ = +0.43 or -0.50 for ¹¹B (1974AS06). At E(³He) = 29.8 MeV a number of ¹¹B states are populated, including suggested T = 3/2 states [see Table 11.19 (in PDF or PS)] with E_x = 12.51 ± 0.05, 12.98 ± 0.09 and 14.40 ± 0.05 MeV, with Γ_c.m. = 260 ± 50, 390 ± 120 and 220 ± 50 keV, respectively. There is a weak indication also of a state at E_x = 14.51 MeV (1971WA21). See also (1969AD1C, 1970BA1P, 1970DU07). For reaction (b) see (1972YO02).

45. (a) ¹¹B(α, α)¹¹B
(b) ¹¹B(α, 2α)⁷Li Q_m = -8.666

Angular distributions have been reported at E_α = 28.3 MeV (1965KO1A: α₀ → α₃, α₄₊₅, α₆), 28.4 and 29.0 MeV (1968KA24: α₀) and 28.5 MeV (1967NA06: α₀ → α₃, α₄₊₅, α₆, α₈). For reaction (b) see (1969FU09).

46. ¹¹B(⁶Li, ⁶Li)¹¹B

The elastic scattering has been measured at E(⁶Li) = 28 MeV (1972BA52) and analyzed by the optical model.

47. ¹¹B(⁹Be, ⁹Be)¹¹B

See (1970LK1A; theor.).

48. (a) ¹¹B(¹⁰B, ¹⁰B)¹¹B
(b) ¹¹B(¹¹B, ¹¹B)¹¹B

See (1975HI1D), and (1967GU1A) for reaction (b).

49. ¹¹B(¹²C, ¹²C)¹¹B

The elastic scattering has been studied at E(¹¹B) = 28 MeV (1969VO07, 1969VO10), at E(¹²C) = 15, 17, 20 and 24 MeV (1974BO15), and at E(¹²C) = 87 MeV (1971LI11). The population of ¹¹B*(2.12, 4.45, 6.79) and of ¹²C*(0, 4.43) has also been reported: see (1969VO07). See also (1974DA1P) and (DE63Y, 1970AN1D; theor.).

50. ¹¹B(¹⁴N, ¹⁴N)¹¹B

The elastic scattering has been investigated at E(¹⁴N) = 41, 77 and 113 MeV (1971LI11).

51. ¹¹B(¹⁶O, ¹⁶O)¹¹B

The elastic scattering has been studied at E(¹⁶O) = 14.5 to 27.5 MeV (1968OK1B) and 27, 30, 32.5, 35 and 60 MeV (1969VO10, 1972SC03, 1974KO1P). See also (1969BR1D, 1971BO1V) and (1970SC1G, 1974DE17; theor.).

52. ¹¹C(β⁺)¹¹B Q_m = 1.982

See ¹¹C.

53. ¹²C(γ, p)¹¹B Q_m = -15.9572

The fraction of transitions to the ground and to excited states of ¹¹B [and to ¹¹C states reached in the (γ, n) reaction] has been measured at E_bs = 24.5, 27, 33 and 42 MeV: the ground state is predominantly populated. The population of analog states in the (γ, n) and (γ, p) reactions are similar: see ¹¹C (1970ME17). See also the discussions in (1973DI1C, 1973SP03, 1974DI17) and in ¹²C. Angular distributions of the p₀₊₁ and the p_2+3+4+5 groups have been measured by (1974FI17: E_γ = 60, 80, 100 MeV). See also (1968FR12) and (1970MU1D, 1971BI01, 1973MS01, 1973MS02; theor.).

54. ¹²C(e, ep)¹¹B Q_m = -15.9572

At E_e = 497 MeV the excitation of ¹¹B*(0, 2.1, 5.) has been observed by Auriol et al. (see (1972RA1E)). See also (1967AM1A), ¹²C and (1968BO1D, 1968CI1B, 1968WA1D, 1969BA1F, 1972BE59, 1974HA14; theor.).

55. ¹²C(n, d)¹¹B Q_m = -13.7325

Angular distributions have been measured at E_n = 56 MeV for the deuterons to ¹¹B*(0, 2.12, 4.45 + 5.02) (1974KI1A).

56. ¹²C(p, 2p)¹¹B Q_m = -15.9572

Gross structure is seen in the summed proton spectrum with Q = -15.6 ± 0.6 and -34.3 ± 0.8 MeV (1965RI1A, 1966TY01), -15.0 ± 0.5 and -35.5 ± 1.0 MeV (1971LA16), corresponding to ¹¹B_g.s. and an excited state with J^π = 1/2⁺ at E_x ≈ 19.5 MeV (ejection of p- and s-protons, respectively). High resolution experiments show groups corresponding to ¹¹B*(0, 2.12, 4.45, 5.02, 6.79) (1965PU02, 1967PU01, 1974ST1R). See also (1969EP01, 1971HA61, 1971HO03, 1972PU1A), (1968AJ02, 1969RU1A, 1973JA01), (1967KO1B, 1969MC13, 1970KA01, 1971YO1E, 1972KO13, 1972LI1J, 1972ST33, 1973GU18, 1973GU1D; theor.) and ¹²C.

57. ¹²C(d, ³He)¹¹B Q_m = -10.4634

Angular distributions of ³He ions have been measured at E_d = 20, 24, 28 MeV (1971IN1C; unpublished: to ¹¹B*(0, 2.12, 4.45, 5.02, 6.74 + 6.79, 7.29, 7.98)), 28 MeV (1968GA13: to g.s.), 28 and 50 MeV (1968DU01: ¹¹B*(0, 6.74)), 28.5 MeV (1966DE1C: to g.s.), 52 MeV (1968HI01: to ¹¹B*(0, 2.12, 4.45, 5.02, 6.74 + 6.79, 7.29)) and 80 MeV (1974AS04: to ¹¹B*(0, 4.45)). A coupled channels Born approximation analysis gives good agreement with the angular distributions: a positive β₂ is suggested by the results (1974AS04): see, however, (1974KU17). See also (1969KA1A, 1973WA1E, 1974DI1A) and (1969TA1D, 1973ST16, 1974ST18; theor.).

58. ¹²C(t, α)¹¹B Q_m = 3.8574

Angular distributions of the α-particles to ¹¹B*(0, 2.12) have been measured at E_t = 1 to 2 MeV (1962GU01), 1.11 to 3.40 MeV (1969ET01 and private communication), 10.1 MeV (1962PU01) and 13 MeV (1965AJ01; also α₂, α₃). Electromagnetic transitions have been studied by (1968BE30): see Table 11.4 (in PDF or PS) (1968BE30) confirm J = 3/2 for ¹¹B*(5.02). See also (1969AR1B) and (1969NA1C; theor.).

59. ¹²C(¹⁰B, ¹¹C)¹¹B Q_m = -7.266

This reaction has been studied at E(¹⁰B) = 100 MeV: ¹¹B_g.s. is much more strongly excited than ¹¹B*(2.12) (1973YO1C, 1973YO1D). The ratios of the yields ¹¹B_g.s./¹¹C_g.s. and ¹¹B*(2.12)/¹¹C*(2.00) have been studied at 100 MeV. They differ from 1 by a few percent at certain angles: the deviations are more pronounced for the first excited states (1974HA1V).

60. ¹²C(¹²C, ¹³N)¹¹B Q_m = -14.014

The angular distribution involving the ground state transitions has been measured at E(¹²C) = 114 MeV (1974AN36). See also (1967WI04, 1969BR1G).

61. ¹²C(¹⁴N, ¹⁵O)¹¹B Q_m = -8.665

See (1966PO1B, 1967BI06, 1967VO1A, 1974AN36). See also (1969BR1D, 1973SC1J) and ¹⁵O in (1976AJ04).

62. ¹²C(¹⁹F, ²⁰Ne)¹¹B Q_m = -3.112

At E(¹⁹F) = 40, 60 and 68.8 MeV angular distributions involving ²⁰Ne _g.s. + ¹¹B_g.s., ²⁰Ne^*_1.63 + ¹¹B_g.s. and ²⁰Ne_g.s. + ¹¹B^*_2.12 (E = 68.8 MeV only) have been measured by (1972SC03). See also (1969VO1D, 1970VO1F) and (1972BO21; theor.).

63. ¹³C(n, t)¹¹B Q_m = -12.4214

Not reported.

64. ¹³C(p, ³He)¹¹B Q_m = -13.1852

At E_p = 50.5 MeV, in addition to ¹¹B*(0, 2.12, 4.45, 5.02, 6.74, 8.92), a state is observed at E_x = 12.94 ± 0.05 MeV, Γ = 350 ± 50 keV. Comparison of the angular distributions of the ³He and of the tritons [in the analog reaction] at E_p = 43.7 and 50.5 MeV lead to the assignments J^π = 1/2^-; T = 3/2 for this state and for ¹¹C*(12.50): the strong proton and the weak α-decay are consistent with this assignment (1968CO26). The T = 3/2 state is also observed at E_p = 40 MeV by (1974BE20): E_x = 12.91 ± 0.03 MeV, Γ = 260 ± 50 keV. ¹¹B*(12.55, 14.33) reported by (1970GO04) in the ¹⁰Be(p, γ)¹¹B reaction are not observed by (1974BE20): see Table 11.19 (in PDF or PS). Angular distributions have been measured to ¹¹B*(0, 2.12, 4.45, 5.02) at E_p = 26.9 to 43.1 MeV (1975MI01) and at 43.7 and 49.6 MeV (1968FL02). See also (1969SC1F).

65. ¹³C(d, α)¹¹B Q_m = 5.1686

Observed proton groups are displayed in Table 11.18 (in PDF or PS) (1970BR23). Angular distributions are reported at E_d = 0.41 to 0.81 MeV (1971PU01: α₀, α₁), 1.0 to 2.7 MeV (1970LI1E: α₀, α₁), 1.4 MeV (1966KL1A: α₀), 3.3 to 4.2 MeV (1963MA24: α₀), 6.8 MeV (1968DE26: α₀ → α₃), 11.7 MeV (1969CU08: α₀ → α₃) and 12.1, 13.3 and 14.1 MeV (1970KL04: α₀ → α₃). See also (1968AJ02), (1967SP09, 1968CO04, 1971LI1K) and ¹⁵N.

66. ¹³C(¹⁷O, ¹⁹F)¹¹B Q_m = -4.864

See (1974CH1Q).

67. ¹⁴C(p, α)¹¹B Q_m = -0.7837

Angular distributions of the α₀ → α₃ groups have been measured at E_p = 18 MeV (1962BR34).

68. (a) ¹⁴N(n, α)¹¹B Q_m = -0.1574
(b) ¹⁴N(n, 2α)⁷Li Q_m = -8.823

Angular distributions for the α₀ and α₁ groups have been measured at E_n = 4.9 MeV (1972KI12), 14.1 MeV (1968BA30 [also α₂₊₃], 1968HS03 [also α₂, α₃, α₄₊₅], 1968MA11, 1973BO26), 14.8 to 18.8 MeV (1971SA31) and 14.9 MeV (1968LE11). See also (1969DI1B, 1970DI1A, 1974TU1A). The angular distribution of the 2.12 MeV γ-ray (E_γ = 2118 ± 5 keV) is isotropic; that for the 4.4 MeV γ-ray shows a weak anisotropy. Both γ-rays are Doppler broadened: τ_m < 100 fsec [see Table 11.5 (in PDF or PS)] (1972NY02). See also (1971NY03) and ¹⁵N in (1976AJ04).

At E_n = 14.1 and 15.7 MeV various states of ¹¹B with 8.9 < E_x < 14.5 MeV appear to be involved in the sequential decay to ⁷Li. Angular correlation results are consistent with J^π = 7/2 and 5/2 for ¹¹B*(9.19, 9.28), respectively (1971SC16).

69. ¹⁵N(α, ⁸Be)¹¹B Q_m = -11.083

At E_α = 72.5 MeV, the excitation of ¹¹B*(0, 2.12, 4.45, 5.02, 6.74) is reported (1974WO1D).

70. ¹⁹F(¹²C, ²⁰Ne)¹¹B Q_m = -3.112

See (1971BO1V).