A=8Be (1984AJ01)

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⁸Be (1984AJ01)

(See Energy Level Diagrams for ⁸Be)

GENERAL: See also (1979AJ01) and Table 8.4 [Table of Energy Levels] (in PDF or PS).

Shell model: (1978RA1B, 1979EL04, 1981BO1Y, 1981RA06, 1981ST22, 1982FI13).

Collective, rotational and deformed models: (1978CA1D, 1979EL04, 1979MA1J, 1980FI09, 1981RA06, 1981ST22, 1982FI13).

Cluster and α-particle models: (1977WU1A, 1979GO24, 1979GR1F, 1979PA22, 1979ZH1C, 1980FU1G, 1980HA1M, 1980IK1B, 1981GA1J, 1981KA1P, 1981KN12, 1981KR1J, 1981ST22, 1982HA1M, 1982TS1A, 1982VA11, 1983KA1K, 1983RO1G).

Special states: (1978CA1D, 1978LA1D, 1978RA1B, 1979AR03, 1979GA1E, 1979HA1E, 1979IN07, 1979KA40, 1980KA28, 1980OK01, 1981BA2P, 1981BO1Y, 1981GA1G, 1981GA1J, 1981KU1H, 1981RA06, 1981SE06, 1981ST22, 1982BI09, 1982FI13, 1982HA1M, 1982OR03, 1983AR07, 1983JO03).

Electromagnetic transitions, giant resonances: (1979KA40, 1979PA22, 1981KN12, 1982HA1M).

Complex reactions involving ⁸Be: (1978BE1G, 1978GU16, 1978VO1A, 1979BE1M, 1979BO22, 1979GE05, 1979HA1E, 1979SI09, 1981BL1G, 1981CH18, 1981GU1B, 1981GU1E, 1981WO1A, 1982GU1K, 1982GUZS, 1982KO17, 1982SH01).

Reactions involving pions and other mesons: (1978GI14).

Hypernuclei: (1978PO1A, 1978SO1A, 1981ST1G, 1981SU1D, 1981WA1J, 1982KO11).

Other topics: (1978FI1C, 1978LA1D, 1978RO17, 1978UL02, 1979AR03, 1979BE1H, 1979EL04, 1979GO24, 1979KA40, 1979KA43, 1979VA1A, 1980AM1B, 1980FI09, 1981BA2P, 1981CA1H, 1981KU1H, 1981SE06, 1981SU1D, 1982BE17, 1982BO01, 1982DE1N, 1982NG01, 1982VA1C, 1983AG1C, 1983AR07, 1983BA2F, 1983FI1J, 1983JO03).

Ground-state properties of ⁸Be: (1978FI1C, 1978OV1A, 1978RO17, 1978SM02, 1978UL02, 1979IN07, 1979KA40, 1979PA22, 1981AV02, 1981CH18, 1981ST22, 1982BO01, 1982FI13, 1982HA1M, 1982NG01, 1982TS1A, 1982ZE1A, 1983AR07).

1. ⁸Be → ⁴He⁴He Q_m = 0.09178

γ_c.m. for ⁸Be_g.s. = 6.8 ± 1.7 eV: see (1974AJ01). See, however, (1979FE1C). See also (1980PE1N, 1980RE1C; theor.).

2. ⁴He(α, γ)⁸Be Q_m = -0.09178

The yield of γ₁, has been measured for E_α = 32 to 36 MeV. The yield of γ₀ for E_α = 33 to 38 MeV is twenty times lower than for γ₁, consistent with E2 decay. An angular correlation measurement at the resonances corresponding to ⁸Be*(16.6 + 16.9) [2⁺; T = 0 + 1] gives δ = 0.19 ± 0.03, γ_γ(M1) = 6.4 ± 0.5 eV [weighted mean of the two published measurements listed in (1979AJ01)]. See also (1975NA12). On the basis of these results there is no evidence for violation of CVC or for the existence of SCC. The E_x of ⁸Be*(3.0) is determined in this reaction to be 3.18 ± 0.05 MeV [see also Table 8.4 (in PDF or PS) in (1974AJ01)]. For all references see (1979AJ01). See also (1979AL34).

3. (a) ⁴He(α, n)⁷Be Q_m = -18.9902 E_b = -0.09178
(b) ⁴He(α, p)⁷Li Q_m = -17.3459
(c) ⁴He(α, d)⁶Li Q_m = -22.3714

The cross sections for formation of ⁷Li*(0, 0.48) [E_α = 39 to 49.5 MeV] and ⁷Be*(0, 0.43) [39.4 to 47.4 MeV] both show structures at E_α ≈ 40.0 and ≈ 44.5 MeV: they are due predominantly to the 2⁺ states ⁸Be*(20.1, 22.2): see (1979AJ01). The excitation functions for p₀, p₂, d₀, d₁ for E_α = 54.96 to 55.54 MeV have been measured in order to study the decay of the first T = 2 state in ⁸Be: see Table 8.5 (in PDF or PS). Cross sections for p₀₊₁ are also reported at E_α = 60.2, 92.4 and 140.0 MeV [see (1979AJ01)] and at E_α = 37.5 to 43.0 MeV (1982SL01; p₀, p₁). The cross section for reaction (c) has been measured at three energies in the range E_α = 46.7 to 49.5 MeV: see (1979AJ01).

The production of ⁶Li, ⁷Li and ⁷Be [and ⁶He] has been studied for E_α = 61.5 to 158.2 MeV by (1982GL01). The production of ⁷Li (via reactions (a) and (b)) in the interaction of cosmic rays with the interstellar medium is discussed: it appears that the cross section is too small to account for the observed ⁷Li abundance and it is suggested that the "missing" ⁷Li was produced in the Big Bang, thus supporting the theory of an open universe (1978GL03, 1982GL01). Inclusive proton and deuteron spectra have been measured at E_α = 110, 130, 158 and 172 MeV (1981PA15). A study of the (α, αp) reaction at E_α = 119 MeV is reported by (1981KA1V) [see for excited states of ⁴He]. See also (1979AL34), (1979RA1C; astrophysics) and (1978SL02).

4. ⁴He(α, α)⁴He E_b = -0.09178

The αα scattering reveals the ground state as a resonance with Q₀ = 92.12 ± 0.05 keV, γ_c.m. = 6.8 ± 1.7 eV, [τ = (0.97 ± 0.24) x 10^-16 sec]. For E_α = 30 to 70 MeV the l = 0 phase shift shows resonant behavior at E_α = 40.7 MeV, corresponding to a 0⁺ state at E_x = 20.2 MeV, γ < 1 MeV, γ_α/γ < 0.5. No evidence for other 0⁺ states is seen above E_α = 43 MeV.

The d-wave phase shift becomes appreciable for E_α > 2.5 MeV and passes through resonance at E_α = 6 MeV (E_x = 3.18 MeV, γ = 1.5 MeV, J^π = 2⁺): see Table 8.4 (in PDF or PS) in (1974AJ01). Five 2⁺ levels are observed from l = 2 phase shifts measured from E_α = 30 to 70 MeV: ⁸Be*(16.6, 16.9) with γ_α = γ [see Table 8.6 (in PDF or PS)], and states with E_x = 20.2, 22.2 and 25.2 MeV. The latter has a small γ_α.

The l = 4 shift rises from E_α ≈ 11 MeV and indicates a broad 4⁺ level at E_x = 11.5 ± 0.3 MeV [γ = 4.0 ± 0.4 MeV]. A rapid rise of δ₄ at E_α = 40 MeV corresponds to a 4⁺ state at 19.9 MeV with γ_α/γ ≈ 0.96; γ < 1 MeV and therefore γ_α < 1 MeV, which is < 5% of the Wigner limit. A broad 4⁺ state is also observed near E_α = 51.3 MeV (E_x = 25.5 MeV).

Over the range E_α = 30 to 70 MeV a gradual increase in δ₆ is observed. Some indications of a 6⁺ state at E_x ≈ 28 MeV and of an 8⁺ state at ≈ 57 MeV have been reported; γ_c.m. ≈ 20 and ≈ 73 MeV, respectively. A resonance is not observed at the first T = 2 state, ⁸Be*(27.49): see Table 8.5 (in PDF or PS). See (1979AJ01) for references.

The elastic scattering has also been studied at E_α = 650 and 850 MeV [see (1979AJ01)] and at E_α = 158.2 MeV (1978NA16), as well as at 4.32 and 5.07 GeV/c (1980BE14). Total cross sections are reported at 0.87 and 2.1 GeV/c (1978JA16). Inclusive inelastic cross sections have been measured at 4.32 and 5.07 GeV/c (1981BA1Q, 1981DU08). Elastic and quasielastic cross sections are reported at 17.9 GeV/c (1980AB1C). At 31, 44, 88 and 125 GeV elastic (at the two higher energies) and inelastic collisions have been studied by (1982BE1T, 1982BE1X). For a study of excited states of ⁴He see (1980KA20). The bremstrahlung cross section has been measured for E_α = 9.35 to 18.7 MeV: see (1974AJ01).

5. ⁶Li(d, γ)⁸Be Q_m = 22.2796

The yield of γ-rays to ⁸Be*(17.64) [1⁺; T = 1] has been measured for E_d = 6.85 to 7.10 MeV. A resonance is observed at E_d = 6962.8 ± 3.0 keV [E_x = 27495.8 ± 2.4 keV, γ_c.m. = 5.5 ± 2.0 keV]; γ_γ = 23 ± 4 eV [1.14 ± 0.20 W.u.] for this M1 transition from the first 0⁺; T = 2 state in ⁸Be, in good agreement with the intermediate coupling model: see Table 8.5 (in PDF or PS). See also (1979AJ01). [The energy at resonance, E_d is ≈ 6965 keV, based on the new Q_m.]

6. ⁶Li(d, n)⁷Be Q_m = 3.381 E_b = 22.2796

Yield curves and cross sections have been measured for E_d = 60 keV to 5.5 MeV and 12 to 17 MeV [see (1979AJ01)], for 48 to 170 keV (1982CE02; n₁γ; deduced S(E)), for 0.4 to 1.0 MeV (1979RU07; activation) and 1.3 to 11.9 MeV (1980GU26). Polarization measurements are reported at E_d = 0.27 to 3.7 MeV. Comparisons of the populations of ⁷Be*(0, 0.43) and of ⁷Li*(0, 0.48) have been made at many energies, to E_d = 7.2 MeV. The n/p ratios are closely equal for analog states, as expected from charge symmetry. See (1979AJ01) for references. See also ⁷Be, (1979EL03) in reaction 10, and (1981HO1E).

7. ⁶Li(d, p)⁷Li Q_m = 5.0255 E_b = 22.2796

Excitation functions have been measured for E_d = 30 keV to 5.4 MeV [see (1979AJ01)], for 36 to 170 keV (1981CE04; p₀, p₁ [from 47 keV]) and for 100 to 180 keV (1979BO33; σ_t). An anomaly is observed in the p₁/p₀ intensity ratio at E_d = 6.945 MeV, corresponding to the first 0⁺; T = 2 state, γ = 10 ± 3 keV, γ_p₀ « γ_p₁; γ_p₀ < γ_d. Polarization measurements have been reported at E_d = 0.6 to 10.9 MeV: see (1979AJ01). See also ⁷Li, (1974FI1D), (1979EL03, 1981HO1E), (1979SE04; theor.) and reaction 10.

8. ⁶Li(d, d)⁶Li E_b = 22.2796

The yield of elastically scattered deuterons has been measured for E_d = 2 to 7.14 MeV; no resonances are observed: see (1974AJ01). See also (1974FI1D) and (1979SE04, 1982LE10; theor.).

9. (a) ⁶Li(d, t)⁵Li Q_m = 0.59 E_b = 22.2796
(b) ⁶Li(d, ³He)⁵He Q_m = 0.90

The cross section for tritium production rises rapidly to 190 mb at 1 MeV, then more slowly to 290 mb near 4 MeV: see (1974AJ01). See also ⁵Li. For reaction (b) see ⁵He.

10. (a) ⁶Li(d, α)⁴He Q_m = 22.3714 E_b = 22.2796
(b) ⁶Li(d, αp)³H Q_m = 2.5574
(c) ⁶Li(d, αn)³He Q_m = 1.7936
(d) ⁶Li(d, 2d)⁴He Q_m = -1.4753

Cross sections and angular distributions (reaction (a)) have been measured at E_d = 30 keV to 13.6 MeV [see (1979AJ01)], at 47 to 147 keV (1981GO19; σ_t), at 100 to 180 keV (1979BO33; σ_t) and at E(⁶Li) = 10 to 31 MeV (1979WA02: 30° yield of α₀ and α* to ⁴He*(20.1)[0⁺]). A critical analysis of the low-energy data has led to a calculation of the reaction rate parameters for thermonuclear reactions for plasma temperatures of 2 keV to 1 MeV (1978CL07). See also (1981GO19). Polarization measurements are reported at E_d = 0.4 to 11.8 MeV and at E(⁶Li) = 0.6 MeV [see (1979AJ01)], at E(pol. ⁶Li) = 0.4 and 0.6 MeV (1981UL1A; TAP), at E_pol.
d = 5.0 to 6.5 MeV and 8.0 to 10.0 MeV (1979RI03; VAP, TAP) and at E_{pol. d} = 7.92 MeV (1981KA21; analyzing powers at θ_lab = 65°).

Pronounced variations are observed in the cross sections and in analyzing powers. Maxima are seen at E_d = 0.8 MeV, γ_lab ≈ 0.8 MeV and E_d = 3.75 MeV, γ_lab ≈ 1.4 MeV. The 4 MeV peak is also observed in the tensor component coefficients with L = 0, 4 and 8 and in the vector component coefficients: two overlapping resonances are suggested. At higher energies all coefficients show a fairly smooth behavior which suggests that only broad resonances can exist. The results are in agreement with those from reaction 4, that is with two 2⁺ states at E_x = 22.2 and 25.2 MeV and a 4⁺ state at 25.5 MeV. See also (1979EL03). A strong resonance is seen in the α* channel [to ⁴He(20.1), J^π = 0⁺] presumably due to ⁸Be*(25.2, 25.5). In addition the ratio of the α*/α differential cross sections at 30° show a broad peak centered at E_x ≈ 26.5 MeV (which may be due to interference effects) and suggest a resonance-like anomaly at E_x ≈ 28 MeV (1979WA02). See also the discussion in (1974AJ01). A_yy = 1 points are reported at E_d = 5.55 ± 0.12 (θ_c.m. = 29.7 ± 1.0°) and 8.80 ± 0.25 MeV (θ_c.m. = 90.0 ± 1.0°) [corresponds to E_x = 26.44 and 28.87 MeV] (1979RI03). At E_d = 6.945 MeV, the α₀ yield shows an anomaly corresponding to ⁸Be*(27.49), the 0⁺; T = 2 analog of ⁸He_g.s.. See also (1979SOZZ).

An R-matrix analysis of the very accurate differential and cross-section measurements by (1977EL09) for ⁶Li(d, n), (d, p) and (d, α) [E_d = 0.1 to 1.0 MeV] has been presented by (1979EL03): non-negligable direct and direct-compound interference are present in the (d, n) and (d, p) processes.

A kinematically complete study of reaction (b) has been reported at E_d = 1.2 to 8.0 MeV: the transition matrix element squared plotted as a function of E_αα* (the relative energy in the channel ⁴He_g.s. + ⁴He*(20.1)[0⁺]) shows a broad maximum at E_x ≈ 25 MeV. Analysis of these results, and of a study of ⁷Li(p, α)α* [see reaction 19] which shows a peak of different shape at E_x ≈ 24 MeV, indicate the formation and decay of overlapping states of high spatial symmetry, if the observed structures are interpreted in terms of ⁸Be resonances (1978GE12, 1980CA13). Cross sections have been measured for reactions (b) [E_d = 117 to 772 keV] and (c) [E_d = 204 to 779 keV] (1979HO04). For reaction (d) see (1980LU1C). See also ⁶Li, (1974AJ01, 1979AJ01) for earlier references, (1983KU1H; applied) and (1978FI1D, 1979SE04, 1980LE07, 1981KU1B; theor.).

11. ⁶Li(t, n)⁸Be Q_m = 16.0223

See (1966LA04, 1974AJ01).

12. (a) ⁶Li(³He, p)⁸Be Q_m = 16.7861
(b) ⁶Li(³He, p)⁴He⁴He Q_m = 16.8779

Angular distributions have been reported at E(³He) = 1.4 to 17 MeV [see (1974AJ01, 1979AJ01)] and in the range E(³He) = 0.46 to 1.85 MeV (1980EL02; very accurate σ(θ); to ⁸Be*(0, 3.0, 16.63, 16.92) and for the protons from reaction (b)) and E(pol. ⁶Li) = 21 MeV (1983KO04; p₀). The population of ⁸Be*(17.64, 18.15, 19.0, 19.4, 19.9) has also been reported: see (1974AJ01).

Reaction (b) proceeds via ⁸Be*(16.63, 16.92): γ = 117 ± 10 and 85 ± 10 keV, respectively. Interference effects are reported: see (1974AJ01). See also ⁹B, (1978AL37, 1982LA20) and (1981DU1F; theor.).

13. (a) ⁶Li(α, d)⁸Be Q_m = -1.5671
(b) ⁶Li(α, 2α)²H Q_m = -1.4753

Deuteron groups have been observed to ⁸Be*(0, 3.0, 11.3 ± 0.4). Angular distributions have been measured at E_α = 15.8 to 48 MeV: see (1974AJ01, 1979AJ01).

A study of reaction (b) shows that the peak due to ⁸Be*(3.0) is best fitted by using γ = 1.2 ± 0.3 MeV. At E_α = 42 MeV the α-α FSI is dominated by ⁸Be*(0, 3.0). See also Table 8.4 (in PDF or PS) in (1974AJ01), (1983GO07) and (1978ZE03, 1980ZE05, 1982BE1K, 1982BE17, 1983BE1P; theor.).

14. (a) ⁶Li(⁶Li, α)⁸Be Q_m = 20.804
(b) ⁶Li(⁶Li, α)⁴He⁴He Q_m = 20.896
(c) ⁶Li(⁶Li, 2d)⁴He⁴He Q_m = -2.951

At E_max(⁶Li) = 13 MeV reaction (a) proceeds via ⁸Be*(0, 3.0, 16.6, 16.9, 22.5). The involvement of a state at E_x = 19.9 MeV (γ = 1.3 MeV) is suggested. Good agreement with the shapes of the peaks corresponding to ⁸Be*(16.6, 16.9) is obtained by using a simple two-level formula with interference, corrected for the effect of final-state Coulomb interaction, assuming γ(16.6) = 90 keV and γ(16.9) = 70 keV: see also Table 8.6 (in PDF or PS). The ratio of the intensities of the groups corresponding to ⁸Be*(16.6, 16.9) remains constant for E(⁶Li) = 4.3 to 5.5 MeV: I(16.6)/I(16.9) = 1.22 ± 0.08. Partial angular distributions for the α₀ group have been measured at fourteen energies for E(⁶Li) = 4 to 24 MeV. See (1979AJ01) for the references.

At E(⁶Li) = 36 to 46 MeV sequential decay (reaction (b)) via ⁸Be states at E_x = 11.4, 16.9 and 19.65 MeV, with γ_lab = 7.8, 2.4 and 3.7 MeV [(Primarily experimental widths. I am grateful to Prof. F.C. Barker for calling this to my attention.)], and ⁸Be*(3.0), is reported by (1979WA13).

Reaction (c) has been studied at E(⁶Li) = 36 to 47 MeV: enhancements in the yield have been observed in the yield of d-d and α-α but not of α - d. These enhancements are due to double spectator poles. Their widths are smaller than predicted from the momentum distribution of α + d clusters in ⁶Li. The enhancements are not due to phase space, FSI, or the involvement of states in ⁴He, ⁶Li or ⁸Be. The strengths of the DSP peaks suggest qualitatively that quasi-free scattering is the basic mechanism producing the d-d or α-α detected pairs (1980WA10, 1981WA15). See also (1982WA07, 1983LA1J; theor.).

15. ⁷Li(p, γ)⁸Be Q_m = 17.2541

Cross sections and angular distributions have been reporteed from E_p = 30 keV to 18 MeV. Gamma rays are observed to the ground (γ₀) and the the broad, 2⁺, excited state at 3.0 MeV (γ₁) and to ⁸Be*(16.6, 16.9) (γ₃, γ₄). Resonances for both γ₀ and γ₁ occur at E_p = 0.44 and 1.03 MeV, and for γ₁ alone at 2, 4.9, 6.0, 7.3, and possibly at 3.1 and 11.1 MeV. In addition broad resonances are reported at E_p ≈ 5 MeV (γ₀), γ ≈ 4 - 5 MeV, and at E_p ≈ 7.3 MeV (γ₁), γ ≈ 8 MeV: see Table 8.7 (in PDF or PS). The E_p ≈ 5 MeV resonance (E_x ≈ 22 MeV) represents the giant dipole resonance based on ⁸Be(0) while the γ₁ resonance, ≈ 2.2 MeV higher, is based on ⁸Be*(3.0). The γ₀ and γ₁ giant resonance peaks each contain about 10% of the dipole sum strength. The main trend between E_p = 8 and 17.5 MeV is a decreasing cross section.

At the E_p = 0.44 MeV resonance (E_x = 17.64 MeV) the radiation is nearly isotropic consistent with p-wave formation, J^π = 1⁺, with channel spin ratio σ(J_c = 2)/σ(J_c = 1) = 3.2 ± 0.5. Radiative widths for the γ₀ and γ₁ decay are displayed in Table 8.8 (in PDF or PS).

A careful study of the α-breakup of ⁸Be*(16.63, 16.92) [both J^π = 2⁺] for E_p = 0.44 to 2.45 MeV shows that the non-resonant part of the cross section for production of ⁸Be*(16.63) is accounted for by an extranuclear direct-capture process. Resonances for production of ⁸Be*(16.63, 16.92) are observed at E_p = 0.44, 1.03 and 1.89 MeV [⁸Be*(17.64, 18.15, 18.9)]. The results are consistent with the hypothesis of nearly maximal isospin mixing for ⁸Be*(16.63, 16.92): decay to these states is not observed from the 3⁺ states at E_x = 19 MeV, but rather from the 2^- state at 18.9 MeV excitation. Squared T = 1 components calculated for ⁸Be*(16.6, 16.9) are 40 and 60%, and 95 and 5% for ⁸Be*(17.6, 18.2). The cross section for (γ₃ + γ₄) has also been measured for E_p = 11.5 to 30 MeV (θ = 90°) by detecting the γ-rays and for E_p = 4 to 13 MeV (at five energies) by detecting the two α-particles from the decay of ⁸Be*(16.6, 16.9): a broad bump is observed at E_p = 8 ± 2 MeV (1981MA33). The angle and energy integrated yield only exhausts 8.6% of the classical dipole sum for E_p = 4 to 30 MeV, suggesting that this structure does not represent the GDR built on ⁸Be*(16.6, 16.9). A weak, very broad [γ ≳ 20 MeV] peak may also be present at E_x = 20 - 30 MeV. A direct-capture calculation adequately describes the observed cross section (1981MA33). For earlier references see (1979AJ01). See also (1982SC1H; applications) and (1979BA1V; theor.).

16. ⁷Li(p, n)⁷Be Q_m = -1.644 E_b = 17.2541

Measurements of cross sections have been reported for E_p = 1.9 to 52 MeV [see (1974AJ01, 1979AJ01)] and at 60.1 to 199.1 MeV (1982WA02; activation σ). Polarization measurements have been reported at E_p = 2.05 to 5.5 MeV, 30 and 50 MeV: see (1974AJ01).

The yield of ground-state neutrons (n₀) rises steeply from threshold and shows pronounced resonances at E_p = 2.25 and 4.9 MeV. The yield of n₁ also rises steeply from threshold and exhibits a broad maximum near E_p = 3.2 MeV and a broad dip at E_p ≈ 5.5 MeV, also observed in the p₁ yield. Multi-channel scattering length approximation analysis of the 2^- partial wave near the n₀ threshold indicates that the 2^- state at E_x = 18.9 MeV is virtual relative to the threshold and that its width γ = 50 ± 20 keV. The ratio of the cross section ⁷Li(p, γ)⁸Be*(18.9) γ/→ ⁸Be*(16.6 + 16.9) to the thermal-neutron-capture cross section ⁷Be(n, γ)⁸Be*(18.9) γ/→ ⁸Be*(16.6 + 16.9), provides a rough estimate of the isospin impurity of ⁸Be*(18.9): σ_p, γ/σ_n, γ ≈ 1.5 x 10^-5 and therefore the T = 1 isospin impurity is < 4% in intensity. See, however, (1979AJ01) and (1977BA62) who finds a 10% impurity.

The structure at E_p = 2.25 MeV is ascribed to a 3⁺, T = (1), l = 1 resonance with γ_n ≈ γ_p and γ²_n/γ²_p = 3 to 10: see (1966LA04). At higher energies the broad peak in the n₀ yield at E_p = 4.9 MeV can be fitted by J^π = 3⁽⁺⁾ with γ = 1.1 MeV, γ²_n ≈ γ²_p. The behavior of the n₁ cross section can be fitted by assuming a 1^- state at E_x = 19.5 MeV and a J = 0, 1, 2, positive-parity state at 19.9 MeV [presumably the 20.1 - 20.2 MeV states reported in reaction 4]. In addition the broad dip at E_p ≈ 5.5 MeV may be accounted for by the interference of two 2⁺ states. See Table 8.9 (in PDF or PS). The total reaction cross section goes down exponentially from E_p = 23 to 199.1 MeV: see (1982WA02). See also ⁷Be, (1977KO46, 1980AU02, 1982AB1D), (1979AJ01, 1982TA03), and (1979CH1C, 1979DU1A; applications).

17. (a) ⁷Li(p, p)⁷Li E_b = 17.2541
(b) ⁷Li(p, p')⁷Li*

Absolute differential cross sections for elastic scattering have been reported for E_p = 0.4 to 12 MeV and at 14.5, 20.0 and 31.5 MeV. The yields of inelastically scattered protons (to ⁷Li*(0.48)) and of 0.48 MeV γ-rays have been measured for E_p = 0.8 to 12 MeV: see (1974AJ01). Polarization measurements have been reported at a number of energies in the range E_p = 0.67 to 155 MeV [see (1974AJ01, 1979AJ01)] and at 2.1 GeV/c (1979ZH1A).

Anomalies in the elastic scattering appear at E_p = 0.44, 1.03, 1.88, 2.1, 2.5, 4.2 and 5.6 MeV. Resonances at E_p = 1.03, 3 and 5.5 MeV and an anomaly at E_p = 1.88 MeV appear in the inelastic channel. A phase-shift analysis and a review of the exisitng cross-section data show that the 0.44 and 1.03 MeV resonances are due to 1⁺ states which are a mixture of ⁵P₁ and ³P₁ with a mixing parameter of +25°; that the 2^- state at a neutron threshold (E_p = 1.88 MeV) has a width of about 50 keV [see also reaction 16]; and that the E_p = 2.05 MeV resonance corresponds to a 3⁺ state. The anomalous behavior of the ⁵P₃ phase around E_p = 2.2 MeV appears to result from the coupling of the two 3⁺ states [resonances at E_p = 2.05 and 2.25 MeV]. The ³S₁ phase begins to turn postive after 2.2 MeV suggesting a 1^- state at E_p = 2.5 MeV: see Table 8.10 (in PDF or PS). The polarization data show structures at E_p = 1.9 and 2.3 MeV. (1979AR10) have performed a phase-shift analysis of the (p, p) data: they find no indication of a possible 1^- state with 17.4 < E_x < 18.5 MeV [see, however, reaction 15 in (1979AJ01)]. The absence of a 1^- state in this E_x region indicates that the shell-model residual interaction for negative-parity, S = 0, T = 0 states of ⁸Be is deficient (1979AR10).

An attempt has been made to observe the T = 2 state [⁸Be*(27.47)] in the p₀, p₁ and p₂ yields. None of these shows the effects of the T = 2 state. Table 8.5 (in PDF or PS) displays the upper limit for γ_p₀/γ. The inclusive cross section has been reported at E_p = 640 MeV (1981ER07). See also (1982AB1D), (1979AJ01) and (1979VE08, 1981BA36, 1983BA2H; theor.).

18. (a) ⁷Li(p, d)⁶Li Q_m = -5.026 E_b = 17.2541
(b) ⁷Li(p, t)⁵Li Q_m = -4.43
(c) ⁷Li(p, ³He)⁵He Q_m = -4.12

The excitation function for d₀ measured for E_p = 11.64 to 11.76 MeV does not show any effect from the T = 2 state [⁸Be*(27.47)]: see (1979AJ01). Poalrization measurements are reported at E_p = 200 and 400 MeV (1981LI1B) and 450 to 530 MeV (1981IR1A) [both prelim.]. See also (1979VE08; theor.).

19. ⁷Li(p, α)⁴He Q_m = 17.3459 E_b = 17.2541

The cross section follows the expression E^-1 e^{-B√E(square root of E)}, with B = 91.5 ± 4.5 keV^1/2, in the range E_p = 23 to 50 keV. The cross section in that interval rises from 0.013 to 2.4 μb. Taking into account ⁸Be J^π = 2⁺ levels at 16.7, 16.9 and 20.6 MeV, an R-matrix fit for E_p = 131 to 561 keV leads to a quadratic energy dependence for the S-factor: S = 0.065[1 + 1.82E - 2.51E²] MeV · b, over the energy range E_p = 0 to 600 keV.

Excitation functions and angular distributions have been measured at many energies in the range E_p = 23 keV to 45.2 MeV [see (1979AJ01)] and at E_p = 47.8, 53.5, 58.5 and 62.5 MeV (1982BA1V). Polarization measurements have been carried out for E_p = 0.8 to 10.6 MeV [see (1974AJ01)]: in the range E_p = 3 to 10 MeV the asymmetry has one broad peak in the angular distribution at all energies except near 5 MeV; the peak value is 0.98 ± 0.04 at 6 MeV and is essentially 1.0 for E_p = 8.5 to 10 MeV.

Broad resonances are reported to occur at E_p = 3.0 MeV [γ ≈ 1 MeV] and at ≈ 5.7 MeV [γ ≈ 1 MeV]. Structures are also reported at E_p = 6.8 MeV and at E_p = 9.0 MeV: see (1979AJ01). The 9.0 MeV resonance is also reflected in the behavior of the A₂ coefficient. The experimental data on the yields and on polarization appear to require including two 0⁺ states [at E_x ≈ 19.7 and 21.8 MeV] with very small α-particle widths, and four 2⁺ states [at E_x ≈ 15.9, 20.1, 22.2 and 25 MeV]. See, however, reaction 4. A 4⁺ state near 20 MeV was also introduced in the calculation but its contribution was negligible. The observed discrepancies are said to be probably due to the assumption of pure T = 0 for these states. At E_p = 11.64 to 11.76 MeV the excitation function does not show any effect due to the T = 2 state at E_x = 27.47 MeV. See (1979AJ01) for references.

A study of the ⁷Li(p, α)⁴He* reaction to ⁴He*(20.1) [0⁺] at E_p = 4.5 to 12.0 MeV shows a broad maximum at E_x ≈ 24 MeV: see reaction 10 (1978GE12, 1980CA13). See also (1981BA1R), (1975ZI1A, 1980PE1N; astrophysics) and (1978FI1D, 1979DO19; theor.).

20. (a) ⁷Li(d, n)⁸Be Q_m = 15.0296
(b) ⁷Li(d, n)⁴He⁴He Q_m = 15.1213

The population of ⁸Be*(0, 3.0, 16.6, 16.9, 17.6, 18.2, 18.9, 19.1, 19.2) has been reported in reaction (a). For the parameters of ⁸Be*(3.0) see Table 8.4 (in PDF or PS) in (1974AJ01). Angular distributions of n₀ and n₁ have been reported at E_d = 0.7 to 3.0 MeV and at E_d = 15.25 MeV. The angular distributions of the neutrons to ⁸Be*(16.6, 17.6, 18.2) are fit by l_p = 1: see (1974AJ01, 1979AJ01).

Reaction (b) appears to proceed primarily via ⁸Be*(3.0, 16.6, 16.9) and ⁵He_g.s.: see (1974AJ01). However, ⁸Be*(11.4) may also be involved [E_x = 11.4 ± 0.05 MeV, γ_c.m. = 2.8 ± 0.2 MeV] as many state(s) at E_x ≈ 20 MeV: see (1979AJ01). See also (1980NE1B), (1978BA1F; applied) and ⁹Be.

21. ⁷Li(t, 2n)⁸Be Q_m = 8.7723

See (1979AJ01).

22. ⁷Li(³He, d)⁸Be Q_m = 11.7606

Deuteron groups are observed to ⁸Be*(0, 3.0, 16.6, 16.9, 17.6, 18.2). For the parameters of ⁸Be*(3.0) see Table 8.4 (in PDF or PS) in (1974AJ01). For the J^π = 1⁺ mixed isospin states see Table 8.6 (in PDF or PS). Angular distributions have been measured for E(³He) = 0.9 to 24.3 MeV [see (1974AJ01, 1979AJ01)] and at E(pol. ³He) = 33.3 MeV (1981BA1P; to ⁸Be*(16.6, 17.6, 18.2)). See also ¹⁰B and (1982AR08).

23. (a) ⁷Li(α, t)⁸Be Q_m = -2.5599
(b) ⁷Li(α, αt)⁴He Q_m = -2.4681

Angular distributions have been measured to E_α = 50 MeV: see (1966LA04, 1974AJ01, 1979AJ01). The ground state of ⁸Be decays isotropically in the c.m. system: J^π = 0⁺. At E_α = 10 MeV an anomaly ("ghost") is observed at E_x ≈ 0.5 MeV. Sequential decay (reaction (b)) is reported at E_α = 50 MeV via ⁸Be*(0, 3.0, 11.4, 16.6, 16.9, 19.9): see (1974AJ01). See also (1978ZE03, 1979ZE1B, 1980ZE05, 1982BE1K, 1983BE1P; theor.).

24. ⁷Li(⁷Li, ⁶He)⁸Be Q_m = 7.280

See ⁶He and (1979AJ01).

25. (a) ⁷Be(n, p)⁷Li Q_m = 1.644 E_b = 18.8984
(b) ⁷Be(n, α)⁴He Q_m = 18.9902
(c) ⁷Be(n, γα)⁴He Q_m = 18.9902

At thermal energies, the (n, p) cross section is (4.8 ± 0.9) x 10⁴ b (1981MUZQ), the (n, α) cross section is ≤ 0.1 mb and the (n, γα) cross section is 155 mb. See also (1974AJ01) and (1983BA2H; theor.).

26. ⁷Be(d, p)⁸Be Q_m = 16.6738

See (1974AJ01).

27. ⁸Li(β^-)⁸Be Q_m = 16.0037

⁸Li decays mainly to the broad 3.0 MeV, 2⁺ level of ⁸Be, which decays into two α-particles. Both the β-spectrum and the resulting α-spectrum have been extensively studied: see (1955AJ61, 1966LA04). See also ⁸B(β⁺). Studies of the distribution of recoil momenta and neutrino-recoil correlation indicate that the decay is overwhelmingly GT, axial vector [see reaction 1 in ⁸Li] and that the ground state of ⁸Li has J^π = 2⁺: see (1980MC07).

Beta-α angular correlations have been measured for the decays of ⁸Li and ⁸B for the entire final-state distribution: see Table 8.10 (in PDF or PS) in (1979AJ01). No evidence was seen for second-class currents. Recently (1980MC07) have measured the β - ν - α correlations as a function of E_x in the decay of ⁸Li and ⁸B, detecting both α-particles involved in the ⁸Be decay. They find that the decay is GT for 2 < E_x < 8 MeV. The absence of Fermi decay strength is expected because the isovector contributions from the tails of ⁸Be*(16.6, 16.9) interfere destructively in this energy region: see (1980MC07). The results are consistent with the CVC predictions (1980MC07). See also (1978FO31), (1978BO30) and (1979DE15, 1980OK01, 1981HO06; theor.).

28. ⁸B(β⁺)⁸Be Q_m = 17.979

The decay [see reaction 1 in ⁸B] proceeds mainly to ⁸Be*(3.0) [see Table 8.4 (in PDF or PS) in (1974AJ01) for its parameters]. Detailed study of the high-energy portion of the α-spectrum reveals a maximum near E_α = 8.3 MeV, corresponding to transitions to ⁸Be*(16.63), for which parameters E_x = 16.67 MeV, γ = 150 to 190 keV or E_x = 16.62 MeV, γ = 95 keV are derived. Log ft = 3.3. The energy distribution of the α-particles has been measured. Analysis of this data and of data from α-α scattering in a three-level R-matrix formalism indicate a 2⁺ state of ⁸Be at E_x = 12.0^-3.0_+3.5 MeV and γ = 14^-3₊₄ MeV (a₂ = 6.0 ± 0.5 fm): see (1974AJ01). For β⁺-α angular correlation studies see reaction 27. See also (1978BO30).

29. (a) ⁹Be(γ, n)⁸Be Q_m = -1.6655
(b) ⁹Be(n, 2n)⁸Be Q_m = -1.6655
(c) ⁹Be(p, pn)⁸Be Q_m = -1.6655
(d) ⁹Be(t, tn)⁸Be Q_m = -1.6655
(e) ⁹Be(α, αn)⁸Be Q_m = -1.6655

Neutron groups to ⁸Be*(0, 3.0) have been studied for E_γ = 18 to 26 MeV: see (1974AJ01, 1979AJ01) and ⁹Be. Reaction (b) appears to proceed largely via excited states of ⁹Be with subsequent decay mainly to ⁸Be*(3.0): see (1966LA04, 1974AJ01), ⁹Be and ¹⁰Be. Reaction (c) has been studied at E_p = 45 and 47 MeV: the reaction primarily populates ⁸Be*(0, 3.0): see (1979AJ01), ⁹Be and ⁹B. See also (1978JE01). For reactions (d) and (e) see (1974AJ01) and ⁹Be. For reaction (e) see (1979AJ01).

30. ⁹Be(π⁺, p)⁸Be Q_m = 138.684

Angular distributions are reported to ⁸Be*(0, 3.0, 11.4) (unresolved) at E_π⁺ = 50 MeV (1980BA43).

31. (a) ⁹Be(p, d)⁸Be Q_m = 0.5591
(b) ⁹Be(p, d)⁴He⁴He Q_m = 0.6509

Angular distributions of deuteron groups have been reported at E_p = 0.11 to 185 MeV [see (1974AJ01, 1979AJ01)], 14.3 and 26.2 MeV (1981BE53; d₀, d₁; and see below), 18.6 MeV (1983BEYY; d₀) and 50 and 72 MeV (1982ZA1B; d₀, d₁ and d) to ⁸Be*(16.9 ± 17.6, 19.2). For spectroscopic factors see (1979AJ01). The angular distributions to ⁸Be*(0, 3.0, 16.9, 17.6, 18.2, 19.1) are consistent with l_n = 1: see (1974AJ01) and (1982ZA1B). For spectroscopic factors see (1979AJ01).

An anomalous group is reported in the deuteron spectra between the d₀ and the d₁ groups. At E_p = 26.2 MeV, its (constant with θ) E_x = 0.6 ± 0.1 MeV. Analyses of the spectral shape and transfer cross sections are consistent with this "ghost" feature being part of the Breit-Wigner tail of the J^π = 0⁺ ⁸Be_g.s.: it contains < 10% of the g.s. transfer strength (1981BE53). See also (1981OV02). An analysis of reported γ_c.m. for ⁸Be*(3.0) in this reaction shows that there is no E_p dependence: (1981BE53) report that the average γ_c.m. at E_p = 14.3 and 26.2 MeV is 1.47 ± 0.04 MeV. γ_c.m. = 5.5 ± 1.3 eV for ⁸Be_g.s. and 5.2 ± 0.1 MeV for ⁸Be*(11.4). Spectroscopic factors for ⁸Be_g.s. (including the "ghost" anomaly) and ⁸Be*(3.0) are 1.23 and 0.22, respectively, at E_p = 14.3 MeV, and 1.53 and 1.02, respectively, at E_p = 26.2 MeV (1981BE53). Studies of the width of ⁸Be*(3.0) in this reaction and in reactions 32, 42, 47 and 51 are reported by (1981OV02): the width is not appreciably (< 10%) reaction dependent but the nearness of the decay threshold indicates that care must be taken in comparing decay widths from reaction and from scattering data. (1981OV02) find a mean E_R = 3130 ± 25 keV (resonance energy in the α + α c.m. system) [E_x = 3038 ± 25 keV] and γ_c.m. = 1.50 ± 0.02 MeV for ⁸Be*(3.0): the corresponding observed and formal reaction widths and channel radii are γ²_R = 580 ± 50 keV, γ²_λ = 680 ± 100 keV and s = 4.8 fm. See (1979AJ01) for the earlier work. For reaction (b) [FSI through ⁸Be*(0, 3.0)] see (1974AJ01) and (1982LA11; E_p = 30 MeV).

32. (a) ⁹Be(d, t)⁸Be Q_m = 4.5918
(b) ⁹Be(d, t)⁴He⁴He Q_m = 4.6836

Angular distributions have been measured for E_d = 0.3 to 28 MeV: see (1979AJ01). At E_d = 27.97 MeV angular distributions of triton groups to ⁸Be*(16.6, 16.9, 17.6, 18.2, 19.1, 19.2, 19.8) have been analyzed using DWUCK: absolute C²S are 0.074, 1.56, 0.22, 0.17, 0.41, 0.48, 0.40 respectively. See also Table 8.6 (in PDF or PS). An isospin amplitude impurity of 0.21 ± 0.03 is found for ⁸Be*(17.6, 18.2) (1977OO01). See also ⁹Be(d, ³He) [reaction 13] in ⁸Li. For a study of the parameters of ⁸Be*(3.0) see reaction 31 (1981OV02).

A kinematically complete study of reaction (b) at E_d = 26.3 MeV indicates the involvement of ⁸Be*(0, 3.0, 11.4, 16.9, 19.9 + 20.1): see (1974AJ01). See also (1982LA09).

33. (a) ⁹Be(³He, α)⁸Be Q_m = 18.9123
(b) ⁹Be(³He, α)⁴He⁴He Q_m = 19.0041

Angular distributions have been measured in the range E(³He) = 3.0 to 26.7 MeV and at E(pol. ³He) = 33.3 MeV (to ⁸Be*(16.9, 17.6, 19.2)) [S = 1.74, 0.72, 1.17, assuming mixed isopsin for ⁸Be*(16.9)]. The possibility of a broad state at E_x ≈ 25 MeV is also suggested. See (1979AJ01) and Table 8.5 (in PDF or PS) here.

Reaction (b) has been studied at E(³He) = 2.9 to 10 MeV [see (1979AJ01)] and at 1.0 to 2.8 MeV (1978AR21, 1979BA27, 1981FA02, 1981FA07). The reaction has been reported to proceed via ⁸Be*(0, 3.0, 11.4, 16.6, 16.9, 19.9, 22.5): see (1979AJ01) and (1978AR21, 1981FA07). In addition, observation of the quasi-free reaction process is reported by (1981FA07). See also ⁹Be and ¹²C in (1980AJ01).

34. (a) ⁹Be(⁶Li, ⁷Li)⁸Be Q_m = 5.585
(b) ⁹Be(⁷Li, ⁸Li)⁸Be Q_m = 0.367
(c) ⁹Be(¹²C, ¹³C)⁸Be Q_m = 3.2809
(d) ⁹Be(¹³C, ¹⁴C)⁸Be Q_m = 6.5110
(e) ⁹Be(¹⁶O, ¹⁷O)⁸Be Q_m = 2.478

Angular distributions (reactions (c) and (e)) have been studied at E(¹²C) = 12 and 15 MeV and E(¹⁶O) = 11, 15 and 18 MeV (1970BA49). See also (1982HU06) for reaction (c). See (1979AJ01) for earlier references.

35. ¹⁰Be(p, t)⁸Be Q_m = 0.0043

Angular distributions for the transition to the first T = 2 state ⁸Be*(27.49), and to ⁸Li*(10.82) reached in the (p, ³He) reaction, are very similar. They are both consistent with L = 0 using a DWBA (LZR) analysis: see (1979AJ01). The particle decay of this state has been studied by (1979FR04): see Table 8.5 (in PDF or PS).

36. ¹⁰B(π^-, 2n)⁸Be Q_m = 130.533

Using stopped pions, ⁸Be states at ≈ 3 and ≈ 19 MeV are populated. The 19 MeV structure may be due to a superposition of three peaks at 17, 19 and 22 MeV: see (1979AJ01).

37. ¹⁰B(n, t)⁸Be Q_m = 0.2299

See (1979AJ01) and ¹¹B in (1980AJ01).

38. ¹⁰B(p, ³He)⁸Be Q_m = -0.5339

At E_p = 39.4 MeV angular distribution measurements have been carried out for the ³He groups to ⁸Be*(0, 3.0, 16.6, 16.9): see (1974AJ01).

39. (a) ¹⁰B(d, α)⁸Be Q_m = 17.8193
(b) ¹⁰B(d, α)⁴He⁴He Q_m = 17.9111

Angular distributions have been reported at E_d = 0.5 to 7.5 MeV: see (1974AJ01, 1979AJ01). At E_d = 7.5 MeV the population of ⁸Be*(16.63, 16.92) is closely the same consistent with their mixed isospin character while ⁸Be*(17.64) is relatively weak consistent with its nearly pure T = 1 character. ⁸Be*(16.63, 16.92, 17.64, 18.15) have been studied for E_d = 4.0 to 12.0 MeV. Interference between the 2⁺ states [⁸Be*(16.63, 16.92)] varies as a function of energy. The cross-section ratios for formation of ⁸Be*(17.64, 18.15) vary in a way consistent with a change in the population of the T = 1 part of the wave function over the energy range: at the higher energies, there is very little isospin violation. At higher E_x only the 3⁺ state at E_x = 19.2 MeV is observed, the neighboring 3⁺ state at E_x = 19.07 MeV is not seen. γ_16.6 = 90 ± 5 keV, γ_16.9 = 70 ± 5 keV, ΔQ = 290 ± 7 keV: see Table 8.6 (in PDF or PS).

In reaction (b) at E_d = 13.6 MeV sequential decay is indicated via ⁸Be*(0, 3.0, 11.4, 16.6 + 16.9, 19.9 + 20.2, 25.2, 27.4, 28.6) and possibly via a state with E_x = 15 MeV, γ = 1.0 ± 0.2 MeV (1981NE08). See (1974AJ01, 1979AJ01) for the earlier work, ¹²C in (1980AJ01) and (1981DU1F; theor.).

40. ¹⁰B(α, ⁶Li)⁸Be Q_m = -4.552

At E_α = 27.2 MeV (1982DO1F) and 150 MeV (1981DEZX) angular distributions are obtained involving ⁸Be*(0, 3.0) + ⁶Li_g.s.. See also (1979AJ01) and ⁶Li.

41. ¹⁰B(⁷Li, ⁹Be)⁸Be Q_m = 10.668

Angular distributions have been obtained at E(⁷Li) = 24 MeV to ⁸Be*(0, 3.0, 11.4): see (1979AJ01).

42. (a) ¹¹B(p, α)⁸Be Q_m = 8.5896
(b) ¹¹B(p, α)⁴He⁴He Q_m = 8.6814

Angular distributions have been measured at E_p = 0.78 to 45 MeV [see (1974AJ01, 1979AJ01)] and at E_p = 125 to 498 keV (1979DA03; α₀) and 6 to 18 MeV (1983BU06; α₀, α₁). For the parameters of ⁸Be*(3.0) see reaction 31 (1981OV02). Reaction (b) has been studied for E_p = 0.15 to 10.5 MeV [see (1974AJ01)] and at 20 MeV (1981LA07). The reaction proceeds predominantly by sequential two-body decay via ⁸Be*(0, 3.0). See also ¹²C in (1980AJ01), (1981HO13) and (1981DU1F; theor.).

43. ¹¹B(d, n)¹²C → ⁸Be + α Q_m = 6.3650

For the decay of excited states of ¹²C to ⁸Be*(0, 3.0), see (1983NEZZ) and ¹²C in (1985AJ01).

44. ¹¹B(³He, ⁶Li)⁸Be Q_m = 4.5714

At E(³He) = 25.6 MeV angular distributions have been obtained for the ⁶Li ions to ⁸Be*(0, 16.6, 16.9, 17.6). In the range E(³He) = 25.2 to 26.3 MeV, the group to ⁸Be*(18.2) [J^π = 1⁺; T = 0] is not observed: its intensity is < 0.15 of the intensity to ⁸Be*(17.6) [J^π = 1⁺; T = 1]: see (1979AJ01).

45. ¹¹B(α, ⁷Li)⁸Be Q_m = -8.756

At E_α = 27.2 MeV angular distributions involving ⁷Li*(0, 0.48) and ⁸Be_g.s. as well as the "ghost" state [see e.g. reaction 31] have been studied by (1983DO1F, 1983DOZX): the cross section for formation of the "ghost" state is anomalously large. See (1979AJ01) and ⁷Li.

46. (a) ¹²C(γ, α)⁸Be Q_m = -7.3665
(b) ¹²C(e, eα)⁸Be Q_m = -7.3665
(c) ¹²C(π⁺, π⁺α)⁸Be Q_m = -7.3665

For reactions (a) and (b) see ¹²C in (1975AJ02, 1980AJ01). For reaction (c) see (1979GI11).

47. (a) ¹²C(n, nα)⁸Be Q_m = -7.3665
(b) ¹²C(p, pα)⁸Be Q_m = -7.3665

These reactions involve ⁸Be*(0, 3.0): see (1974AJ01, 1979AJ01), (1983AN02; reaction (a) at E_n = 10 - 35 MeV) (1981DE08; reaction (b) at E_p = 45 MeV) and ¹²C in (1980AJ01). See also (1978GO14; theor.) and ¹³C in (1981AJ01, 1986AJ01) and ¹³N in (1981AJ01, 1886AJ01).

48. (a) ¹²C(d, ⁶Li)⁸Be Q_m = -5.891
(b) ¹²C(d, dα)⁸Be Q_m = -7.3665

Angular distributions have been obtained at E_d = 12.7 to 51.8 MeV [see (1974AJ01, 1979AJ01)] and at E_d = 13.6 MeV (1981DO15; to ⁸Be*(0) and to "ghost" anomaly), 54.25 MeV (1980YA02: to ⁸Be*(0, 3.0, 11.4)). S_α = 0.79, 1.08, 1.27 for ⁸Be*(0, 3.0, 11.4) [FRDWBA] (1980YA02). For the parameters of ⁸Be*(3.0) see reaction 31 (1981OV02). For reaction (b) see (1979HE06). See also (1978BE1H) and (1983GA1J; theor.).

49. ¹²C(³He, ⁷Be)⁸Be Q_m = -5.7789

Angular distributions have been obtained at E(³He) = 25.5 to 70 MeV [see (1979AJ01)] and at 41 MeV (1981LE01): ⁸Be*(0, 3.0, 11.4, 16.6, 16.9, 17.6) have been populated. See also ⁷Be.

50. (a) ¹²C(α, 2α)⁸Be Q_m = -7.3665
(b) ¹²C(α, ⁸Be)⁸Be Q_m = -7.4583

This reaction has been studied up to E_α = 104 MeV: see (1979AJ01). Angular correlations involving ⁸Be*(0, 3.0) have been studied at E_α = 90 MeV: S_α (PWIA) = 2.9 ± 0.4 and 2.8 ± 0.3, respectively; S_α (DWIA) for ⁸Be_g.s. = 2.4 ± 0.4. Angular distributions at E_α = 65 MeV (reaction (b)) lead to S_α = 0.55 and 0.75 (DWBA) for ⁸Be*(0, 3.0). ⁸Be*(11.4) was also observed. Reaction (a) has also been studied at E_α = 65 MeV (1983YA01). See also (1981RU10), (1978BE1G), (1981BA20; theor.), ¹²C in (1985AJ01) and ¹⁶O in (1982AJ01).

51. ¹²C(⁹Be, ¹³C)⁸Be Q_m = 3.2809

Angular distributions involving ⁸Be_g.s. + ¹³C_g.s. have been reported at E(⁹Be) = 20 to 22.9 MeV (1979BO06) and at E(¹²C) = 10.5, 12.0 and 13.5 MeV (1982TA21).

52. ¹²C(¹²C, ¹⁶O)⁸Be Q_m = -0.2046

Angular distributions involving ⁸Be_g.s. + ¹⁶O_g.s. have been reported at E(¹²C) = 11.9 to 22 MeV (1980WA16, 1982TA21) and at ≈ 37 MeV (see (1979AJ01)). See also ¹⁶O in (1977AJ02, 1982AJ01). For ⁸Be*(3.0) see (1981OV02). See also (1979GO1C).

53. ¹²C(¹⁶O, ²⁰Ne)⁸Be Q_m = -2.632

See reaction 20 in ²⁰Ne in (1983AJ01).

54. ¹³C(p, ⁶Li)⁸Be Q_m = -8.613

See ⁶Li.

55. ¹³C(d, ⁷Li)⁸Be Q_m = -3.587

See ⁷Li and (1981DO15).

56. ¹³C(³He, ⁸Be)⁸Be Q_m = 8.1731

Angular distributions have been obtained at E(³He) = 3.3, 5.0 and 5.8 MeV for the transition to ⁸Be_g.s. + ⁸Be_g.s.: see (1974AJ01). See also ¹⁶O in (1982AJ01).

57. ¹³C(α, ⁹Be)⁸Be Q_m = -10.7392

See (1979BE1J).

58. ¹³C(⁹Be, ¹⁴C)⁸Be Q_m = 6.5110

An angular distribution involving ⁸Be_g.s. and ¹⁴C_g.s. has been obtained at E(⁹Be) = 28.8 MeV (1980BO21).

59. ¹⁶O(α, ¹²C)⁸Be Q_m = -7.2537

See (1980BE04, 1980BE15) and (1979AJ01).

60. ²⁴Mg(e, e'¹⁶O)⁸Be Q_m = -14.138

See (1979SAZM).