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GENERAL: See also (1979AJ01) and Table 8.2 [Table of Energy Levels] (in PDF or PS).

Special states: (1980OK01).

Complex reactions involving ⁸Li: (1978BO1B, 1978DU1B, 1979BO22, 1979IV1A, 1980AN1T, 1980BO31, 1980GR10, 1980WI1L, 1981BO1X, 1981MO20, 1982BO35, 1982BO40, 1982GO1E, 1982GU1H, 1982MO1N).

Muon and neutrino interactions: (1978BA1G).

Reactions involving pions and other mesons: (1977VE1C, 1979BA16, 1980HA29, 1981JU1A, 1981NI03, 1982HA57).

Hypernuclei: (1978PO1A, 1979BU1C, 1980BE30, 1980DO1A, 1980IW1A, 1980MA1Z, 1982PI1J, 1982RA1L, 1981ST1G, 1981WA1J, 1982KO11).

Other topics:(1978SO1A, 1979BE1H, 1982NG01).

Ground state of ⁸Li:(1981AV02, 1982NG01).

1. 8Li(β-)8Be

Qm = 16.0037

The β^- decay leads mainly to ⁸Be*(2.9): see ⁸Be, reaction 27. A recent measurement of the half-life is 836 ± 3 msec (1979MI1E). The value derived from a weighted means calculation using the earlier measurements (± 4 - 8 msec) quoted in (1974AJ01) and this recent value gives 840 ± 2 msec. We adopt 836 ± 6 msec, the value measured by (1971WI05). Log ft = 5.60 (M.J. Martin, private communication). See also (1981KO1D) and reaction 27 in ⁸Be.

2. 6Li(t, p)8Li

Qm = 0.801

Angular distributions have been obtained at E_t = 23 MeV for the proton groups to ⁸Li*(0, 0.98, 2.26, 6.54 ± 0.03); Γ_c.m. for ⁸Li*(2.26, 6.54) = 35 ± 10 and 35 ± 15 keV, respectively; J for the latter is ≥ 4 (1978AJ02). See also (1983AB1A).

3. 7Li(n, γ)8Li

Qm = 2.033

The cross section for capture radiation has been measured for E_n = 40 to 1000 keV; it decreases from 50 μb to 5 μb over that interval. The cross section shows the resonance corresponding to ⁸Li*(2.26): E_res = 254 ± 3 keV, Γ_n = 31 ± 7 keV, Γ_γ = 0.07 ± 0.03 eV: see Table 8.3 (in PDF or PS) and (1974AJ01). See also (1981MUZQ).

4. 7Li(n, n)7Li

Eb = 2.033

The thermal cross section is 0.97 ± 0.04 b, σ_free = 0.97 ± 0.04 b (1981MUZQ), 1.06 ± 0.03 b (1982AL16), the scattering amplitude (bound) = -2.29 ± 0.02 fm (1981MUZQ). Total cross-section measurements have been reported for E_n = 5 eV to 30 MeV [see (1974AJ01, 1979AJ01)] and at E_n = 2 to 100 keV (1982AL16; ± 3%), and at E_n = 2.99 to 49.64 MeV (1979KEZU, 1979LAZP) and 0.1 to 49.6 MeV [J.A. Harvey, private communication]. Elastic cross sections are also reported at E_n = 4.0 to 7.5 MeV (1979KN01; also n₀₊₁) and 7.47 to 13.94 MeV (1979HO11). See also (1977BI12, 1980BA2Q, 1980MI02, 1981KN03) and ⁷Li. For polarization measurements see (1974AJ01) and (1982AL16).

A pronounced resonance is observed at E_n = 254 keV with J^π = 3⁺, formed by p-waves: see Table 8.3 (in PDF or PS). A good account of the polarization is given by the assumption of levels at E_n = 0.25 and 3.4 MeV, with J^π = 3⁺ and 2^-, together with a broad J^π = 3^- level at higher energy. [However, the 2^- state is in contradiction with the work of (1982AL16).] Broad peaks are reported at E_n = 4.6 and 5.8 MeV (± 0.1 MeV) [⁸Li*(6.1, 7.1)] with Γ ≈ 1.0 and 0.4 MeV, respectively, and there is indication of a narrow peak at E_n = 5.1 MeV [⁸Li*(6.5)] with Γ ≪ 80 keV and of a weak, broad peak at E_n = 3.7 MeV: see (1974AJ01) and (1979KEZU). See also reaction 5.

5. (a) 7Li(n, n')7Li		Eb = 2.033
(b) 7Li(n, n')3H + 4He	Qm = -2.4681

The excitation function for 0.48 MeV γ-rays shows an abrupt rise from threshold (indicating s-wave formation and emission) and a broad maximum (Γ ≈ 1 MeV) at E_n = 1.35 MeV. A good fit is obtained with either J^π = 1^- or 1⁺ (2⁺ not excluded), Γ_lab = 1.14 MeV. At higher energies a prominent peak is observed at E_n = 3.8 MeV (Γ_lab = 0.75 MeV) and there is some indication of a broad resonance (Γ_lab = 1.30 MeV) at E_n = 5.0 MeV: see (1974AJ01). [(1980OL06) do observe the onset of a resonance at 5 MeV.] The E_n = 3.8 and 5.0 MeV resonances are attributed to (2⁺, 3⁺) and (3⁺, 3^-) states at ⁸Li*(5.4, 6.4): see however reaction 1 here and (1978ST20). At higher energies there is some evidence for structures at E_n = 6.8 and 8 MeV followed by a decrease in the cross section to 20 MeV: see (1979AJ01). For other cross-section measurements see (1979AJ01), (1980OL06; E_n = 0.48 → 5.0 MeV; 0.48 γ) and (1979HO11; E_n = 8.0 → 13.9 MeV; n₀₊₁, n₂). See also (1977BI12, 1980MI02). The cross section for reaction (b) rises to 450 mb at E_n ≈ 8 MeV and thereafter decreases slowly to 300 mb at E_n = 15 MeV (1976GAYV). In the range E_n = 6.89 to 8.96 MeV σ_ave = 372 mb (± 4%) (1981SM04). Measurements are also reported for E_n = 6.0 to 9.97 MeV by (1981LI22). See also (1977BI12), (1980KA1R, 1982SH1K; applied) and (1979BE1K; theor.).

A multilevel multichannel R-matrix analysis of ⁷Li + n, including all available elastic and inelastic scattering data, has recently been presented by (1981KN03). Six additional states of ⁸Li are derived from the analysis at E_x = 2.83 [1^-], 3.91 [0⁺], 4.20 [0^-], 4.57 [2^-], 4.73 [1^-] and 7.81 [2^-] MeV [J^π]. The states shown in Table 8.2 (in PDF or PS) at 3.21, 5.4, 6.1, 7.1 and (9) MeV are located by (1981KN03) at 3.17 [1⁺], 5.45 [3^-], 5.94 [4^-], 6.61 [1^-] and 8.63 [2⁺, 3⁺] MeV [J^π]. The sharp state ⁸Li*(6.53) was not included in the analysis.

6. (a) 7Li(n, 2n)6Li	Qm = -7.2501	Eb = 2.033
(b) 7Li(n, p)7He	Qm = -10.42
(c) 7Li(n, d)6He	Qm = -7.750

For reactions (a) and (c) see (1980MI02). See also ⁶He and ⁶Li and (1979AJ01).

7. 7Li(d, p)8Li

Qm = -0.192

Angular distributions of the p₀ and p₁ groups [l_n = 1] at E_d = 12 MeV have been analyzed by DWBA: S_exp = 0.87 and 0.48 respectively for ⁸Li*(0, 0.98). Angular distributions have also been measured at several energies in the range of E_d = 0.49 → 3.44 MeV (p₀) and 0.95 to 2.94 MeV (p₁). The lifetime of ⁸Li*(0.98) is 10.1 ± 4.5 fsec: see (1979AJ01). See also (1981HU1G, 1982EL03, 1982WAZS) and ⁹Be.

8. 8He(β-)8Li

Qm = 10.653

See ⁸He.

9. 9Be(γ, p)8Li

Qm = -16.887

See (1976MA34).

10. 9Be(e, ep)8Li

Qm = -16.887

At E_e = 500 MeV, ⁸Li*(0, 0.98, 2.26) are populated (1977TU1C, 1979BA1U; prelim.): a large structure at E_x ≈ 25 MeV, mostly of 1s strength, is also reported. See also (1979AJ01, 1979MO1G) and ⁹Be.

11. 9Be(π+, π+p)8Li

Qm = -16.887

The population of ⁸Li*(0.98) and its subsequent γ-decay are reported by (1978MO01).

12. 9Be(p, 2p)8Li

Qm = -16.887

The summed proton spectrum at E_p = 156 MeV shows peaks corresponding to ⁸Li(0) and ⁸Li*(0.98 + 2.26) [unresolved]. In addition s-states [J^π = 1^-, 2^-] are suggested at E_x = 9 and 16 MeV, with Γ_c.m. ≈ 6 and 8 MeV; the latter may actually be due to continuum protons: see (1974AJ01). See also (1979JA1C) and (1980CA1A).

13. 9Be(d, 3He)8Li

Qm = -11.393

Angular distributions have been reported for the ³He ions to ⁸Li*(0, 0.98, 2.26, 6.53) at E_d = 28 MeV [C²S (abs) = 1.63, 0.61, 0.48, 0.092] and 52 MeV. The distributions to ⁸Li*(6.53) [Γ < 100 keV] are featureless: see (1979AJ01).

14. 9Be(t, α)8Li

Qm = 2.927

At E_t = 12.98 MeV, angular distributions of the α-particles to ⁸Li*(0, 0.98, 2.26, 6.53 ± 0.02 [Γ_c.m. < 40 keV] have been measured: see (1974AJ01). At E_{pol. t} = 17 MeV, σ(θ) and A_y measurements, analyzed by CCBA, lead to J^π = 4⁺ for ⁸Li*(6.53) (1981AR19). For ⁸Li*(0.98), τ_m = 14 ± 5 fsec, E_x = 980.80 ± 0.10 keV: see (1974AJ01).

15. 9Be(α, 5Li)8Li

Qm = -18.85

See ⁵Li (1981DA03).

16. 9Be(7Li, 8Be)8Li

Qm = 0.367

The production of vector polarized ⁸Li ions has been studied by (1981KO1D) in this reaction as well as in the ⁷Li(pol. ⁷Li, ⁶Li)⁸Li reaction. See also (1979AJ01).

17. 10Be(p, 3He)8Li

Qm = -15.981

At E_p = 45 MeV, ³He ions are observed to a state at E_x = 10.8222 ± 0.0055 MeV (Γ_c.m. < 12 keV): the angular distributions for the transition to this state, and to its analog (⁸Be*(27.49)), measured in the mirror reaction [¹⁰Be(p, t)⁸Be] are very similar. They are both consistent with L = 0 using a DWBA (LZR) analysis: see (1979AJ01).

18. 10B(6Li, 8B)8Li

Qm = -17.730

See (1979AJ01).

19. 11B(n, α)8Li

Qm = -6.632

Angular distributions for the α₀ and α₁ groups have been measured at E_n = 14.1 MeV [see (1974AJ01)] and 14.4 MeV (1979AN18). See also ¹²B in (1980AJ01).

20. 12C(α, 8B)8Li

Qm = -41.440

See (1974AJ01).