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GENERAL: See also (1979AJ01) and Table 7.7 [Table of Energy Levels] (in PDF or PS).

Nuclear models: (1978RE1A, 1979WI1B, 1980HA1M, 1981KU13, 1982FI13, 1983WA1M).

Astrophysical questions: (1978BU1B, 1979MO04, 1979RA20, 1979RA1C, 1980CA1C, 1980LA1G, 1980WI1M, 1983LI01).

Applied work: (1979LA1E, 1982HA1D, 1983HA1W).

Complex reactions involving ⁷Be: (1978DI1A, 1978DU1B, 1978HA40, 1978HE1C, 1979BO22, 1979KA07, 1979LO11, 1979PO10, 1979RA20, 1979SC1D, 1979VI05, 1980GR10, 1980MI01, 1980WI1K, 1980WI1L, 1980WO05, 1981CI03, 1981GR08, 1981ME13, 1981MO20, 1981TA22, 1982BO1J, 1982BO1N, 1982BO35, 1982FU04, 1982GL01, 1982GR09, 1982GU1H, 1982HA1V, 1982HI12, 1982LU01, 1982LY1A, 1982MO1N, 1983PU01, 1983SA06).

Reactions involving pions and kaons: (1978WA1B, 1979AL1J, 1979BO23, 1979SI16, 1980BA27, 1980LE02, 1981OS04, 1981SI09, 1982AL31, 1982DO02, 1982LEZY, 1983IRZZ, 1983PIZW).

Hypernuclei: (1978PO1A, 1978SO1A, 1981WA1J).

Other topics: (1979BE1H, 1982NG01).

Ground state of ⁷Be: (1982FI13, 1982NG01).

1. 7Be(ε)7Li

Qm = 0.862

The decay is complex: see ⁷Li.

2. 4He(3He, γ)7Be

Qm = 1.5876

The capture cross section has been measured for E_α = 0.38 to 5.80 MeV [see (1974AJ01)], 0.250 to 2.954 MeV (1982KR05), 0.385 to 2.730 MeV (1982OS02), at E_c.m. = 0.897 MeV (1983RO1C) and for E(³He) = 19 to 26 MeV (1983WA05; γ₀₊₁ excitation function at 90°).

The branching ratios DC → 429/DC → 0 and the cross section for the DC → 429 branch have been measured for E_c.m. = 107 to 1266 keV: the branching ratio is approximately constant at 0.43 ± 0.02 over that energy range; the cross section is 0.117 ± 0.016 nb at 107 keV. It increases to 421 ± 39 nb at E_c.m. = 1266 keV (1982KR05). These data lead to a value of S(0) = 0.56 ± 0.03 keV · b (using microscopic DC model calculations, and a branching ratio, 10.42 ± 0.06%, for the ⁷Be decay to ⁷Li*(0.48)) [see reaction 28 in ⁷Li] (1983VO01). (1982OS02) obtain S(0) = 0.52 ± 0.03 keV · b and (1983RO1C) find 0.63 ± 0.04 keV · b. See also (1974AJ01) and (1981WI04; theor.). (1983RO1C) suggest, prior to (1983VO01), that S(0) = 0.56 ± 0.07 keV · b should be adopted. C²S = 1.0 for ⁷Be*(0, 0.43) (1982KR05). See also (1980BA1P, 1980BA2M, 1980PE1N, 1981BA2F, 1981RO1W, 1982BA80; astrophysics) and (1981KI01, 1981LI01, 1982TA1G, 1983WA1M; theor.).

3. (a) 4He(3He, 3He)4He		Eb = 1.5876
(b) 4He(3He, p)6Li	Qm = -4.0182

Elastic scattering studies have been reported for E = 1.72 to 140 MeV [see (1974AJ01, 1979AJ01)] and at E_α = 0.25 to 2.95 MeV (1982KR05) and 140 MeV (1980RO03) and at E(³He) = 18 to 70 MeV (1978BA75) and 198.4 MeV (1980RO03). Polarization measurements have been carried out at E = 4.3 to 98 MeV: see (1979AJ01).

For l ≤ 4, only f-wave phase shifts show resonance structure for E(³He) < 18 MeV, corresponding to ⁷Be*(4.57, 6.73, 9.27): see Table 7.7 (in PDF or PS). No structure corresponding to ⁷Be*(7.21) (J^π = 5/2^-) is seen in the elastic data. The s-wave phase shift is somewhat greater than hard-sphere. The decay of ⁷Be*(9.27) (J^π = 7/2^-) to ⁶Li(0) requires f-shell configuration admixture. An estimate of the yield of ground-state protons relative to those corresponding to ⁶Li*(2.19) yields γ²(p₀)/γ²(p₁) = (16⁺⁵_-10)%. A phase-shift analysis (single-level R-matrix) has been carried out for E(³He) = 18 to 32 MeV: the p-wave phase shifts indicate a 1/2^- state at E_x ≈ 16.7 MeV (E_r = 26.4 MeV), with Γ = 6.5 MeV (1978LU05). The work of (1978BA75) is consistent with the results of (1978LU05) and, in addition, suggests broad l = 4 and 5 states at E(³He) > 30 MeV [E_x > 19 MeV].

The differential cross section for reaction (b) has been determined for E(³He) = 8 to 28 MeV [see (1979AJ01)] and at E_α = 22.2 to 26.5 MeV (1980NE08; p₀). Resonances are observed corresponding to ⁷Be*(7.21, 9.27) in the p₀ yield, to ⁷Be*(9.27) in the p₁ yield and to states at E_x ≈ 10 MeV (T = 1/2) and 11.0 MeV (T = 3/2) in the yield of 3.56 MeV γ-rays. The evidence for the latter derives mainly through interference arguments. There is also some evidence for an extremely broad J^π = 1/2^- structure at E_x ≥ 10 MeV [see also ⁶Li(p, p)]: see Table 7.8 (in PDF or PS) and (1974AJ01). See also (1980NE08). See aslo (1981BA1Q), (1978BR1A, 1979KA1G, 1982YA1A) and (1978DU1D, 1978TA1A, 1979KOZV, 1979LE11, 1979WI1B, 1981FI1B, 1981SH07, 1982AZ01, 1982FU01, 1982KA11, 1982LE23, 1983HO1F, 1983SA1G; theor.).

4. 4He(α, n)7Be

Qm = -18.9902

See (1978GL03, 1979AL34), (1979AJ01) and ⁸Be.

5. 6Li(p, γ)7Be

Qm = 5.606

Gamma transitions are observed to the ground (γ₀) and to the 0.43 MeV (γ₁) states. The yield shows no evidence of resonance for E_p = 0.2 to 1.0 MeV and the branching ratio remains approximately constant at (62 ± 5)% to the ground state, 38% to ⁷Be*(0.43), < 4% to ⁷Be*(4.57): see (1974AJ01). The total cross section for E_p = 0.2 to 1.2 MeV has been obtained by (1979SW02): at E_p = 0.8 MeV it is 3.1 ± 0.4 μb, in good agreement with previous values. The branching ratio to ⁷Be*(0.43) is (41 ± 3)% (1979SW02). The weighted mean of this and previous measurements is (39 ± 2)% (1979SW02). See also (1980BA34).

6. (a) 6Li(p, p)6Li		Eb = 5.606
(b) 6Li(p, 2p)5He	Qm = -4.59
(c) 6Li(p, pα)2H	Qm = -1.4753

Measurements of elastic angular distributions have been reported for E_p = 0.5 to 600 MeV: see (1966LA04, 1974AJ01) and ⁶Li. Two resonances are reported at E_p = 1.84 and 5 MeV in the elastic yield [⁷Be*(7.21, 9.9)]. The parameters of the lower resonance are shown in Table 7.4 (in PDF or PS). The 5 MeV resonance has Γ ≈ 1.8 MeV and appears to also be formed by p-waves: γ²_p is then 3 ± 2 MeV · fm. A weak rise near E_p = 8 to 9 MeV may indicate a further level, ⁷Be* ≈ 13 MeV. A broad resonance at E_p = 14 MeV has also been suggested. Polarization measurements have been carried out for E_p = 1.2 to 155 MeV [see (1974AJ01, 1979AJ01)] and at E_{pol. p} = 25 and 35 MeV (1982ROZT; 0₀, p₁) and 800 MeV (1979GL1C; p₂). A phase shift analysis for E_p = 0.5 to 5.6 MeV shows that only ²S, ⁴S and ⁴P are involved. The ⁴P_5/2 phase resonates at E_p = 1.8 MeV, and the broad resonance at 5 MeV can be reproduced equally well by either ⁴P_3/2 or ⁴P_1/2: tensor polarization measurements are necessary to distinguish between the two: see (1974AJ01).

The reaction cross section for formation of ⁶Li*(2.19) has been measured for E_p = 3.6 to 9.40 MeV: a broad resonance indicates the presence of a state with E_x ≈ 10 MeV, Γ = 1.8 MeV, J^π = (3/2, 5/2)^-, T = 1/2. The cross section and angular distributions of p₂ (⁶Li*(3.56)) for E_p = 4.26 to 9.40 MeV is analyzed in terms of two J^π = 3/2^- states at E_x ≈ 10 and 11 MeV: see reaction 3. The total cross section for formation of ⁶Li*(3.56) decreases slowly with energy for E_p = 24.3 to 46.4 MeV. The reaction cross section has been measured for E_p = 25.0 to 48 MeV: see (1979AJ01).

For reaction (b) see ⁵He, (1978NA18; E_{pol. p} = 635 MeV) and (1979AJ01). For reaction (c) see ⁶Li and (1979AJ01). Studies of inclusive cross sections are reported at 640 MeV (1981ER07) and 400 GeV (1979BA28, 1979FR12, 1980NI09). For pion and kaon production see (1980NI09; 400 GeV). See also (1982AB1D) and (1981BR21, 1981FR1R, 1981FR1T, 1981KR15, 1982ST15; theor.).

7. 6Li(p, n)6Be

Qm = -5.070

Eb = 5.606

The yield of neutrons increases approximately monotonically from threshold to E_p = 14.3 MeV. Polarization measurements are reported at E_p = 30 and 50 MeV: see (1974AJ01). See also ⁶Be.

8. 6Li(p, α)3He	Qm = 4.0182	Eb = 5.606
	Q0 = 4018.2 ± 1.1 keV: see (1981RO02)

Over the range E_p = 25 to 50 keV, the cross section rises from 0.8 to 72 μb: in the formula σ ≈ E^-1e^{-B/√E(square root of E)}, B = 90 ± 6 keV^1/2. Cross-section measurements for E_p = 62 to 188 keV show deviation from an s-wave Gamow plot above ≈ 130 keV (1966GE11). Using cross-section measurements at E_p = 136 → 297 keV, as well as the (1966GE11) results, (1979EL10) calculate S(0) = 3.145 MeV · b [E_c.m. = 1 keV → 500 keV]. Thermonuclear reaction rates are also derived (1979EL10). See also (1979SH14; 125 → 700 keV; S(0) = 3 MeV · b) and (1979AJ01).

At higher energies the cross section exhibits a broad, low maximum near E_p = 1 MeV and a pronounced resonance at E_p = 1.85 MeV (Γ < 0.5 MeV). No other structure is reported up to E_p = 5.6 MeV. Measurements between E_p = 0.4 and 3.4 MeV show that the polarizations are generally large and positive. The E_p = 1.9 MeV resonance appears in A₁ and A₂: see (1974AJ01).

Angular distributions have been reported for E_p = 0.15 to 45 MeV [see (1974AJ01, 1979AJ01)] and at E_p = 125 to 700 keV (1979SH14), 136 to 297 keV (1979EL10) and 47.8, 53.5, 58.5 and 62.5 MeV (1982BA1V). See also (1979DE1E, 1979HA1C, 1980HA1Y, 1981JA1F; applied), (1981HO1E) and (1978PL1A; theor.).

9. 6Li(d, n)7Be

Qm = 3.381

Angular distributions of the n₀ and n₁ groups have been measured at E_d = 0.20 to 15.25 MeV: see (1974AJ01, 1979AJ01). The n-γ correlations are isotropic, indicating J^π = 1/2^- for ⁷Be*(0.43). Broad maxima are observed in the ratio of low-energy to high-energy neutrons at E_d = 4.2 and 5.1 MeV [⁷Be*(6.5, 7.2), Γ_c.m. = 1.2 and 0.5 MeV, respectively]: see (1966LA04). See also (1979HO04, 1980GU26) in ⁸Be.

10. 6Li(3He, d)7Be

Qm = 0.112

Angular distributions of the d₀ and d₁ groups to ⁷Be*(0, 0.43) have been measured at E(³He) = 8, 10, 14 and 18 MeV: all the distributions show an l = 1 maximum at small angles: see (1974AJ01). At E(pol. ³He) = 33.3 MeV angular distributions and A_y measurements to ⁷Be*(0, 0.43) have been analyzed using coupled channels and DWBA. ⁷Be*(4.57) is also populated (1981BA38).

11. 6Li(α, t)7Be

Qm = -14.208

See (1979AJ01).

12. (a) 7Li(γ, π-)7Be	Qm = -140.429
(b) 7Li(π+, π0)7Be	Qm = 3.742

For reaction (a) see (1979BO23). Forward-angle differential cross sections to ⁷Be_g.s. have been measured at E_π⁺ = 48 MeV (1982LEZY), and 70 → 180 MeV (1980BA27, 1982DO02). See also (1982AL35).

13. 7Li(p, n)7Be

Qm = -1.644

The excitation energy of ⁷Be*(0.43) is 429.20 ± 0.10 keV, τ_m = 192 ± 25 fsec: see (1979AJ01). Angular distributions of n₀ and n₁ are reported at E_p = 1.9 to 50 MeV [see (1974AJ01, 1979AJ01)] and at 119.8 MeV (1979GO16, 1980GO07; n₀₊₁). The population of ⁷Be*(4.55, 6.51, 7.19, 10.79) has also been observed: see (1974AJ01, 1979AJ01). The ratios σ₁/σ₀ (⁷Be*(0.43)/⁷Be_g.s.) have been measured at 24.8, 35 and 45 MeV: an analysis of these yields the ratio of spin-flip to spin-nonflip strength |V_στ/V_τ|² (1980AU02). 1983TAZY report cross-section measurements at E_p = 60 to 200 MeV. See also (1981SH1F, 1982KI1F, 1982TAZQ), (1979CH1B, 1980SE1D, 1982SA1M; applied), (1982GO1C, 1982PE06, 1982TA03), (1982GU1D, 1983GU1G; theor.) and ⁸Be.

14. 7Li(3He, t)7Be

Qm = -0.881

Angular distributions of t₀ and t₁ have been measured at E(³He) = 3.0 to 4.0 MeV [see (1974AJ01)] and at E(pol. ³He) = 33.3 MeV (1981BA37). The width of ⁷Be*(4.57), Γ_c.m. = 175 ± 7 keV: see (1974AJ01). See also ¹⁰B.

15. 9Be(p, t)7Be

Qm = -12.082

Angular distributions of tritons have been measured at E_p = 43.7 MeV (⁷Be*(0, 0.43, 4.57, 6.51, 11.01)) and 46 MeV (⁷Be*(0 + 0.43, 4.57, 6.51, 10.69)), and at E_p = 50 and 72 MeV (1982ZA1B; t₀, t₁). The 11 MeV state has E_x = 11.01 ± 0.04 MeV, Γ = 298 ± 25 keV, J^π = 3/2^-, T = 3/2 [the J^π; T assignments are based on the similarity of the angular distribution to that in the (p, ³He) reaction to ⁷Li*(11.13)]: see (1979AJ01).

16. 9Be(3He, 5He)7Be

Qm = -0.88

See reaction 23 in ⁵He.

17. 10B(p, α)7Be

Qm = 1.146

Angular distributions have been measured for E_p = 2.8 to 7.0 MeV: see (1974AJ01). E_x = 428.89 ± 0.13 keV (1979RI12). See also ¹¹C in (1980AJ01, 1985AJ01).

18. 10B(d, 5He)7Be

Qm = -1.97

See (1982DOZT).

19. 10B(3He, 6Li)7Be

Qm = -2.873

See ⁶Li.

20. 10B(α, 7Li)7Be

Qm = -16.200

At E_α = 45.6 MeV the angular distributions of the ⁷Li and of the ⁷Be ions, corresponding to the ground-state transitions, have been measured. At a given angle the intensities of the two ions are the same, implying that the wave functions of the ground states of ⁷Li and ⁷Be are very similar: see (1974AJ01).

21. 12C(γ, nα)7Be

Qm = -26.265

See (1979KI04).

22. 12C(p, 6Li)7Be

Qm = -22.565

See ⁶Li.

23. 12C(d, 7Li)7Be

Qm = -17.539

See ⁷Li.

24. 12C(3He, 8Be)7Be

Qm = -5.779

Angular distributions are reported at E(³He) = 25.5 to 30 MeV involving ⁷Be*(0, 0.43) [see (1979AJ01)] and at 41 MeV (1981LE01) and ¹⁵O in (1981AJ01).

25. 12C(α, 9Be)7Be

Qm = -24.691

At E_α = 42 MeV, angular distributions have been measured involving ⁷Be*(0, 0.43) and ⁹Be_g.s.: see (1974AJ01).

26. 13C(p, 7Li)7Be

Qm = -20.261

See ⁷Li.

27. 16O(3He, 12C)7Be

Qm = -5.5744

Angular distributions are reported at E(³He) = 25.5, 30 and 70 MeV to ⁷Be*(0, 0.43) and various states of ¹²C [see ¹²C in (1980AJ01)] and at 41 MeV (1981LE01).

28. 16O(α, 13C)7Be

Qm = -21.2058

See ¹³C in (1981AJ01).

29. 19F(d, 14C)7Be

Qm = -7.140

The angular distributions to ⁷Be*(0, 0.43) + ¹⁴C_g.s. has been measured at E_d = 14.9 MeV: see (1974AJ01).

30. (a) 19F(3He, 15N)7Be	Qm = -2.426
(b) 20Ne(3He, 16O)7Be	Qm = -3.146

See ¹⁵N in (1981AJ01) and ¹⁶O in (1982AJ01).