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See Table 5.3 [Table of Energy Levels] (in PDF or PS).

1. 3H(3He, n)5Li

Qm = 10.297

Not reported.

2. 3He(d, γ)5Li

Qm = 16.555

The excitation curve measured from E_d = 0.2 to 2.85 MeV shows a broad maximum at E_d = 0.45 ± 0.04 MeV (E_γ = 16.6 ± 0.2, σ = 50 ± 10 μb, Γ_γ = 11 ± 2 eV). Above this maximum, non-resonant capture is indicated by a slow rise of the cross section. The radiation appears to be isotropic to ± 10% at E_d = 0.58 MeV, consistent with s-wave capture (1954BL89). See also (1955KU1B), (1955BA1G; theor.).

3. (a) 3He(d, p)4He	Qm = 18.351	Eb = 16.555
(b) 3He(d, np)3He	Qm = -2.226

Cross sections and angular distributions for reaction (a) from E_d = 35 keV to 10 MeV are given in (1957JA37); see also (1957BO79, 1957FI1A). Below 100 keV the cross section follows the simple Gamow form: σ = (18.2 × 10³/E)exp(-91E^-1/2) b (E in keV) (1953JA1A, 1954AR02). A pronounced resonance occurs at E_d = 430 keV, of about 450-keV width. The peak cross section is given as 0.695 ± 0.014 b by (1952BO68, 1955KU03) and 0.92 ± 0.07 b by (1953YA02, 1954FR01). The resonance is closely fitted with the one-level dispersion formula, using the parameters listed in Table 5.2 (in PDF or PS) (see ³H(d, n)⁴He). See also (1955BA1G, 1955HA1B, 1955JO1A, 1956KL1A), (1958PO1A; theor.).

The angular distribution of protons is isotropic near resonance and shows froward peaking at higher energies; the similarity to ³H(d, n)⁴He is very close. See also (1955KU1B, 1957BO79, 1957BR23).

Above E_d = 3.71 MeV, deuteron breakup (reaction (b)) is observed (1955HE90).

4. 3He(d, d)3He

Eb = 16.555

Differential cross sections for E_d = 0.4 to 3 MeV are plotted in (1957JA37); see also (1952AL36, 1957BR23, 1957FI1A). In the range E_d = 380 to 570 keV, θ_c.m. = 65°, the scattering cross section is considerably below Rutherford scattering and is consistent with s-wave formation of a J = 3/2⁺ state. Above E_d = 2 MeV, the distributions are quite similar to those observed in ³H(d, d)³H (1952AL36, 1954BR05, 1957BR23).

5. 3He(3He, p)5Li

Qm = 11.062

The proton spectrum at E(³He) = 360 keV shows an unresolved ground-state group superposed on a broad continuum. No evidence is found for well-defined proton groups of lower energy than the ground-state group (1954GO18). See also (1953AL1A), (1957BR18) and ⁶Be.

6. 4He(p, p)4He

Eb = -1.796

Differential elastic scattering cross sections have been measured at numerous energies from 0.95 to 95 MeV, as indicated in Table 5.4 (in PDF or PS); curves at several energies are given by (1957JA37) and (1957BR28). Phase shifts derived from the experimental data are listed in the table. At E_p = 40 MeV, the differential cross section shows "diffraction" maxima and minima characteristic of the optical model (1957BR24: see also (1956BU95, 1957GI14, 1957HO1C, 1958GA13)). Recent surveys of the experimental and theoretical situation are reported by (1958GA13, 1958HO1B, 1958MI93).

Even at low energies, the phase shift analysis clearly requires a splitting of P_1/2 and P_3/2 levels, generally attributed to spin-orbit effect. Either order of the P-doublet can be used to fit the cross section data (1949CR1A, 1952DO30): that the P_3/2 state is the lower is established by measurements of the polarization of scattered protons (1952HE15, 1955SC1A, 1956JU10, 1958SC1A). The tabulated phase shifts apply to this case.

The P_3/2 phase shift shows a pronounced resonance effect, passing through 90° at E_p = 2.8 MeV (1949CR1A), while the P_1/2 changes only slowly over a range of several MeV. Analysis by (1952DO30), based on resonance theory, yields for the P_3/2 level (ground state of ⁵Li) E_λ(c.m.) = -4.1 MeV, γ²_λ = 25 × 10^-13 MeV-cm and for the P_1/2, E_λ(c.m.) = 3.4 MeV, γ²_λ = 105 × 10^-13 MeV-cm (see also (1952AD09)). (These widths correspond to θ²_p = 0.9 and 3.9 times the sum-rule limit, respectively, using R = 2.9 × 10^-13 cm.) It thus appears that the P_1/2 state, if resonance theory is at all appropriate here, is extremely broad and located 5 - 10 MeV above the ground state. A new analysis of all data < 18 MeV yields E_res(lab) = 2.6 MeV, γ²_p = 12 × 10^-13 MeV-cm, θ²_p = 0.40 for the ground state and E_res(lab) = 10.8 MeV, γ²_p = 30 × 10^-13 MeV-cm, θ²_p = 1.0 for the excited state, using R = 2.6 × 10^-13 cm (1958MI93). The s-wave phase shifts are well accounted for by hard-sphere scattering, with R = 2.9 × 10^-13 cm (1952AD09, 1952DO30: see, however, (1956VA1C)), R = 2.0 × 10^-13 cm (1958MI93). Semi-empirical phase shifts and polarizations for E_p = 10 to 40 MeV are given by (1958GA13).

Proton and neutron scattering in helium are discussed in terms of a central potential with spin-orbit interaction by (1954BR1B, 1954HO1B, 1954JA1A, 1954SA1B, 1955HO1C, 1958GA13). (1955HO1C) obtain a good account of the s- and p-wave interactions with a Gaussian potential and Serber exchange force. The effect of tensor forces is discussed by (1956FE1A). See also (1956AB1A, 1956LE1C, 1958HO1B).

Polarization of the scattered protons is discussed by (1949CR1A, 1952AD09, 1952DO30, 1952HE15, 1955SC1A, 1956BR1D, 1956JU10, 1957RO1A, 1957SC1B, 1957SE40, 1958BR24, 1958SC1A, 1958SC27) and others.

For α-scattering in hydrogen: see (1954JU1B, 1954RU1A, 1957RO1A). See also (1956EI05, 1957TY27).

7. (a) 4He(p, d)3He	Qm = -18.351	Eb = -1.796
(b) 4He(p, pn)3He	Qm = -20.577

Angular distributions are reported at E_p = 27.9 MeV (1957WI22), 31.6 MeV (1952BE1A) and 95 MeV (1955TE1A) for reaction (a). The cross section at E_p = 40 MeV, θ = 30°, is 10 ± 1 mb/sr (1956EI05). For reaction (b), see (1957WI22) and (1956EI05).

8. 4He(p, 2p)3H

Qm = -19.812

Eb = -1.796

See (1957WI22) and (1956EI05).

9. 4He(d, n)5Li

Qm = -4.023

At E_d = 13 MeV, a broad, asymmetric neutron group corresponding to the ground state is observed. There is no evidence for structure corresponding to the P_1/2 excited state (1956BO1F, 1956BO43).

10. 6Li(γ, n)5Li

Qm = -5.494

The photoneutron threshold is 5.4 ± 0.2 MeV (1951TI06), 5.35 ± 0.2 MeV (1951SH63), 5.6 ± 0.1 MeV (1955TI1A), 5.73 ± 0.05 MeV (1958RY77). An earlier reported higher state is not confirmed (1955TI1A).

11. 6Li(p, d)5Li	Qm = -3.267
	Q0 = -3.0 ± 0.15 (1955LI09).

At E_p = 18.6 MeV, the ground-state group appears as a broad, asymmetric peak (Γ = 1.8 MeV) which tails off to a low continuum at lower energies. The angular distribution of the ground-state group has a maximum at 15° (c.m.) and, at small angles, conforms with stripping theory (l_n = 1) (1955LI09).

12. 6Li(d, t)5Li	Qm = 0.765
	Q0 = 0.80 ± 0.15 (1958FR52).

At E_d = 1 MeV a broad ground-state triton group is observed (Γ_c.m. = 1.5 MeV). The distribution of protons from the ⁵Li breakup indicates a pronounced forward distribution (1958FR52). Se also ⁸Be.

13. 6Li(3He, α)5Li

Qm = 15.084

See (1955AL57) and (1953KU24).

14. 7Li(p, t)5Li

Qm = -4.262

This reaction has been observed at E_p = 17.5 MeV (1957MA04).