A=11B (2012KE01)

TUNL Nuclear Data
Evaluation Home Page

Information on mass
chains and nuclides

3 4

5 6

7 8

9 10

11 12

13 14

15 16

17 18

19 20

Group Info

Publications

HTML

General Tables

Level Diagrams

Tables of EL's

NSR Key# Retrieval

ENSDF

Excitation Functions

Thermal N Capt.

G.S. Decays

Half-Lives Table

TUNL Dissertations

NuDat at BNL

Useful Links

Citation Examples

Home

Sitemap

Directory

Email Us

WWW TUNL

¹¹B (2012KE01)

(See 2 [Electromagnetic Transitions in A = 11] (in PDF or PS), 11.18 (in PDF or PS), 11.19 (in PDF or PS) and Energy Level Diagram for ¹¹B and Isobar Diagram)

μ = +2.6886489 (10) nm (1989RA17),

Q = 40.65 ± 0.26 mb (1970NE05),

B(E2; 3/2^- → 1/2^-) = 2.6 ± 0.4 e² ⋅ fm⁴ (1980FE07).

1. ⁴He(⁷Li, α₀) E_b = 8.6641

A 13.7 MeV ⁷Li beam impinged on a thick ⁴He gas filled chamber and the spectrum of elastically scattered α particles, measured in a position sensitive ΔE-E Si telescope, was evaluated to determine the ⁷Li(α, α) excitation function (2011YA02). An array of NaI detectors surrounding the target excluded participation of ⁷Li*(0.48). States deduced from an R-matrix analysis are presented in 11.20 (in PDF or PS).

2. ⁶Li(⁶Li, p)¹¹B Q_m = 12.2169

At E(⁶Li) = 2 to 16 MeV, angular distributions have been measured for the proton groups corresponding to the first eight states of ¹¹B (1987DO05) and for p₀, p₁, p₂, p₆, p₇ and p₉ (1990LE05). For the earlier work see (1980AJ01). For excitation functions see ¹²C. See also (1987DO07).

3. ⁷Li(α, γ)¹¹B Q_m = 8.6641

Resonances for capture radiation are displayed in 11.21 (in PDF or PS). See also (1995DE05, 1996RE16, 1999AN35, 2004GY02, 2010ZH21).

4. ⁷Li(α, n)¹⁰B Q_m = -2.7900 E_b = 8.6641

The total cross section has been measured from threshold to E_α = 5.67 MeV [see also reaction 25]: a broad maximum at E_α ≈ 5.1 MeV (σ_max = 40 mb) is observed (1984OL05). The neutron spectrum and neutron-to-γ-ray radiation yield of Li-²⁴¹Am₂O₃ and Li-²³⁸PuO₂ sources are evaluated in (1993VL02). For the earlier work see 11.7 (in PDF or PS) in (1985AJ01). See also (1985CA41; astrophys.).

5. ⁷Li(α, t)⁸Be Q_m = -2.5595 E_b = 8.6641

Excitation functions have been measured for E_α = 14 to 25 MeV (t₀) and 18 to 25 MeV (t₁): see (1980AJ01). See also ⁸Be in (2004TI06) and (1987DM1C).

6. ⁷Li(α, α)⁷Li E_b = 8.6641

The elastic scattering and the scattering to ⁷Li*(0.48) have been studied at many energies up to E_α = 22.5 MeV: see (1975AJ02, 1980AJ01, 1985AJ01). Observed resonances are displayed in 11.22 (in PDF or PS). For α-⁷Li correlations see (1987PO03).

7. ⁷Li(⁶Li, d)¹¹B Q_m = 7.1903

Angular distributions have been measured for E(⁷Li) = 3.3 to 5.95 MeV: see (1975AJ02).

8. (a) ⁷Li(⁷Li, t)¹¹B Q_m = 6.1965
(b) ⁷Li(⁷Li, ¹¹B*)

For reaction (a), angular distributions have been measured at E(⁷Li) = 2.10 to 16 MeV. See (1975AJ02) for references. At E(⁷Li) = 2 to 16 MeV angular distributions and excitation functions for p, t and α cluster transfer were measured and evaluated using a DWBA analysis (2010RO09). While proton transfer was found to be nearly a 100% direct process, the α-particle transfer, to ¹¹B was more complex. On average the ¹¹B_g.s. and states at ¹¹B*(2.12, 4.44, 5.02) were populated 20 to 60 % by direct processes; compound nucleus processes were found to be less than 20%. At E(⁷Li) = 79.6 MeV transitions are observed to several ¹¹B states; ¹¹B_g.s. is particularly strongly populated (1974CE06).

For reaction (b) at E(⁷Li) = 50.9 MeV (2003FL02), states at ¹¹B*(11.3, 12.5, 14.3) were observed in the ⁷Li + α relative energy spectra, and at E(⁷Li) = 58 MeV (2005CU06) states shown in 11.23 (in PDF or PS) were populated. The observations confirm the T = 1/2 nature of the 12.6 MeV and 14.3 MeV states, and the small Γ_t/Γ_α ratio for ¹¹B*(12.6) supports the suggestion of (2004SO28) that this state is the 9/2⁺ member of the K^π = 3/2⁺ cluster band.

9. (a) ⁷Li(⁹Be, α + ⁷Li) Q_m = -2.3077
(b) ⁷Li(⁹Be, α + α + t)

At E(⁹Be) = 55 MeV (2005SO13) and 70 MeV (2004SO19, 2004SO28, 2005SO13) states at ¹¹B*(9.3, 10.2, 10.55, 11.2, (11.4), 11.8, 12.5, (13.0), 13.1, (14.0), 14.35, (17.4) and (18.6)) are observed in reaction (a). It is suggested that these states may have a 2α + t cluster structure. These T = 1/2 states have some overlap with T = 3/2 states and may indicate isospin mixing. The states at E_x = 12.5, 14.35, 17.45 MeV are believed to be IAS of low-lying ¹¹Be states.

For reaction (b), participation of ⁸Be*(0, 3.04) and ⁷Li*(4.65, 6.6) is found in the reconstruction of ¹¹B*(13.1, 14.4, 17.5) states from α + α + t coincidences. Also see (2007FR22).

10. ⁸Li(α, n)¹¹B Q_m = 6.6315

Reaction cross sections have been measured at E_cm = 0.9 to 2.8 MeV (2004MI34), E_cm = 0.6 to 2.7 MeV (2004HA54, 2006IS04), E_cm = 1.05 MeV (2008LA08, 2010LA07), E_cm = 1.25 MeV, E_cm = 1.5 to 7 MeV (2000MI34) and E(⁸Li) = 10 to 20 MeV (1992BO06). Various ¹²B resonances are observed. Rates for the reaction path ⁸Li(α, n)¹¹B(n, γ)¹²B(β)¹²C are crucial for computing the formation of A > 12 nuclei in inhomogeneous Big Bang Nucelosynthesis (1992BO06, 1993DE30, 2000MI34, 2004CH22). Early estimates for the ⁸Li(α, n) reaction rate were based on the inverse reaction, ¹¹B(n, α), see i.e. (1990PA22, 1991PA26); however, such measurements are only sensitive to the n₀ contribution to the total cross section. The direct measurements with ⁸Li beams indicate participation of ¹¹B excited states and a much larger total cross section. Systematic issues are evident when comparing inclusive (⁸Li, n) and exclusive (⁸Li, n + ¹¹B) results: see (2006IS04). A novel experiment approached the issue by impinging a ⁸Li beam on a ⁴He gas target that was located inside a zero-energy-threshold 4π ³He proportional counter embedded in a polyethylene moderator (2008LA08, 2010LA07). See (2000MI34) for branching ratios to n₀ through n₉. Also see discussion in (1992RA04, 1993OB01, 1994KU28, 1996DE02, 2003SO22), and see (2011AU01) for a discussion of ¹¹B production in core-collapse supernovae.

11. ⁹Be(d, γ)¹¹B Q_m = 15.8162

The θ = 90° γ₀ differential cross section has been measured for E_d = 0.5 to 11.9 MeV: see (1975AJ02). 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. Resonant behavior is observed in the θ = 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 (1974DE01).

12. ⁹Be(d, n)¹⁰B Q_m = 4.3621 E_b = 15.8162

The cross section follows the Gamow function for E_d = 70 to 110 keV. 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: see (1975AJ02). Thick target yields for γ-rays have been measured at E_d = 48 to 170 keV: see (1985AJ01). Thick target yields are also reported at E_d = 14.8, 18.0 and 23.0 MeV: see (1980AJ01). Polarization measurements have been carried out at E_d = 0.4 to 5.5 MeV [see (1975AJ02, 1980AJ01)] and at E_{pol. d} = 12.3 MeV: see (1985AJ01). See also ¹⁰B in (2004TI06).

13. (a) ⁹Be(d, p)¹⁰Be Q_m = 4.5877 E_b = 15.8162
(b) ⁹Be(d, α)⁷Li Q_m = 7.1521
(c) ⁹Be(d, t)⁸Be Q_m = 4.5927

Measurements of proton yields have been carried out at E_d ≤ 6.0 MeV for p₀ and p₁ [see (1975AJ02, 1980AJ01, 1985AJ01)]. The p₀ and p₁ yields show a resonance at E_d = 750 ± 15 keV [¹¹B*(16.43), Γ ≈ 40 keV] and the p₁ yield resonates at 1.85 MeV [¹¹B*(17.33), Γ_cm ≈ 1.0 MeV] and 2.3 MeV [¹¹B*(17.70), sharp]. See also (1975AJ02, 1985AJ01) for other possible structures. Polarization of the protons has been measured at E_d = 1 to 21 MeV [see (1975AJ02, 1980AJ01, 1985AJ01, 1990AJ01)] and at E_{pol. d} = 2.5 to 3.0 MeV (1995LY03). See also ¹⁰Be in (2004TI06).

The yield of α-particles (reaction (b)) has been measured for E_d = 0.3 to 14.43 MeV [see (1975AJ02, 1980AJ01, 1985AJ01)]. The 0.75 MeV resonance, observed in reaction (a), is weakly populated in the α₀ yield. The VAP was measured for α₀₊₁ at E_d = 2.0 to 3.0 MeV and compiled for 1.4 to 3.0 MeV (1994LY02); analysis shows influence from ¹¹B*(17.33, 17.43, 17.7, 18.0). For other polarization measurements see references in (1985AJ01, 1990AJ01). Also see ⁷Li in (2002TI10).

The cross section for reaction (c) has been measured for E_d = 0.15 to 19 MeV: see (1968AJ02, 1975AJ02, 1980AJ01), and for E_d = 3 to 11 MeV (1995AB41). Resonant structures are reported by (1995AB41) near ¹¹B*(18.1, 19.5, 22.4, 24.4). Polarization measurements are reported at E_{pol. d} = 12 and 15 MeV [see (1980AJ01, 1990AJ01)] and at E_{pol. d} = 2.5 to 3.0 MeV (1994LY02). In the analysis of (1994LY02), which included VAPs for E_d = 1.4 to 3.0 MeV, an anomaly near E_d = 2.4 MeV is attributed to a resonance at E(¹¹B) ≈ 17.8 MeV, which could be the IAS to ¹¹Be*(5.25). See also ⁸Be in (2004TI06).

See (1997YA02, 1997YA08) for measurements of ⁹Be + d astrophysical S-factors at E_d = 57 to 139 keV.

14. ⁹Be(d, d)⁹Be E_b = 15.8162

Excitation functions for elastically scattered deuterons have been measured for E_d = 0.4 to 7.0 MeV and for 12.17 to 14.43 MeV (also d₁, d₂) [see (1975AJ02, 1980AJ01)]. Polarization measurements have been reported at E_{pol. d} = 6.3 to 15 MeV [see (1975AJ02, 1980AJ01, 1990AJ01)]. See also a ⁹Be in (1988AJ01).

15. ⁹Be(t, n)¹¹B Q_m = 9.5590

Angular distributions have been measured at E_t = 1.1 to 1.7 MeV (n₀, n₁, n₂, n₆, n₈, n₉): see (1980AJ01).

16. ⁹Be(³He, p)¹¹B Q_m = 10.3228

Observed proton groups are displayed in 11.24 (in PDF or PS). Angular distributions have been obtained at a number of energies in the range E(³He) = 1.0 to 38 MeV [see (1980AJ01, 1985AJ01, 1990AJ01)]. It is suggested that the T = 1/2 strength is strongly fragmented (1982ZW02). See also ¹²C in (1990AJ01).

17. ⁹Be(α, d)¹¹B Q_m = -8.0303

Angular distributions have been measured at a number of energies in the range E_α = 23.4 to 30.2 MeV [see (1980AJ01, 1990AJ01)]. The predominant L-transfers are L = 0, 2; 0; 0 for ¹¹B*(0, 2.12, 5.02). The angular distribution to ¹¹B*(4.44) is flat at E_α = 27 MeV. At E_α = 48 MeV, ¹¹B*(16.44, 17.69, 18.0, 19.15) are not excited suggesting that these states are rather pure T = 3/2 states (1982ZW02): also see ⁹Be(³He, p)¹¹B 11.24 (in PDF or PS).

18. ⁹Be(⁶Li, α)¹¹B Q_m = 14.3425

Angular distributions have been determined for seven α-groups at E(⁶Li) = 3 to 4 MeV, and at 24 MeV to ¹¹B*(0, 2.12) and to a number of unresolved levels with E_x ≤ 13.2 MeV: see (1968AJ02, 1975AJ02). For the breakup reactions see (1975AJ02).

19. ⁹Be(¹¹B, ¹¹B)⁹Be

Angular distributions for elastic and inelastic scattering have been measured at E(¹¹B) = 45 MeV (2003RU02). Distributions for ¹¹B*(2.12, 4.445, 5.020, 6.743 + 6.792, 7.28, 7.978, and 8.560) were analyzed with an emphasis on determining the large angle scattering mechanism which is sensitive to the short range nucleus-nucleus interaction. Deformation parameters were deduced for ⁹Be and ¹¹B states.

20. ¹⁰Be(p, γ)¹¹B Q_m = 11.2285

The yield of γ₀ has been measured at 90° for E_p = 0.6 to 6.3 MeV. Observed resonances are displayed in 11.25 (in PDF or PS). T = 3/2 assignments are made for the states at E_x = 12.56, 12.91, 14.33 and 15.32 MeV whose energies match those of the first four states of ¹¹Be [compare with the T = 3/2 states reported in ⁹Be(³He, p)¹¹B - 11.24 (in PDF or PS) and 11.34 (in PDF or PS)]. Several known T = 1/2 states in ¹¹B are not observed in this reaction: see 11.18 (in PDF or PS). Parameters of the 12.56 MeV state are discussed in (2006FO14, 2007BA54).

21. ¹⁰Be(p, n)¹⁰B Q_m = -0.2256 E_b = 11.2285

The reaction cross section has been measured for E_p = 0.89 to 1.93 MeV: the excitation of ¹¹B*(12.56, 12.91) is reported (1986TE1A and G.M. Ter-Akopian, private communication; 1987ERZY). See also (1988DU06; theor.).

22. ¹⁰B(n, γ)¹¹B Q_m = 11.4541
Q₀ = 11454.1 ± 0.2 keV (1986KO19)

Values reported for the thermal capture cross section are inconsistent. The Atlas of Neutron Resonances evaluation gives the value σ_γ = 305 ± 16 mb (2006MUZX); an earlier evaluation of the thermal capture cross sections reported σ_γ = 0.5 ± 0.1 b (2003MUZZ). At the same time, the results of the measurements and analysis for the Evaluated Gamma-ray Activation File (EGAF) project deduced σ_γ = 303 ± 20 mb (2003LI1L), but the value σ_γ = 390 ± 11 mb was later published by that group (2008FIZZ). The earlier reported values are σ_γ = 0.29 ± 0.04 b (1986KO19) and 0.5 ± 0.2 (1957BA18, 1973MU14). Reviewing these reported values, we accept the value σ_γ = 305 ± 16 mb from the Atlas of Neutron Resonances (2006MUZX). The observed capture γ-rays are displayed in 11.26 (in PDF or PS). A compilation of thermal capture data is in (2002RE13).

23. (a) ¹⁰B(n, n)¹⁰B E_b = 11.4541
(b) ¹⁰B(n, n')¹⁰B

Coherent neutron scattering lengths and free cross sections were measured to determine the spin-dependent scattering length (1983KO17, 2006MUZX). The coherent scattering length b(¹⁰B) = -0.2 ± 0.4 fm (1983KO17) and the total free scattering cross section σ₀ = 2.23 ± 0.06 b (1970AS10) are used to deduce the spin state scattering lengths a₊ = -3.8 ± 0.4 fm, a_- = 4.7 ± 0.4 fm, b₊ = -4.2 ± 0.4 fm and b_- = 5.2 ± 0.4 fm which implies a vanishing coherent scattering cross section. Therefore neutron scattering on ¹⁰B is totally incoherent (1983KO17). 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. For a display of cross sections and a listing of measurements see (1988MCZT).

Total cross section measurements in the range E_n = 10 to 500 keV show a broad maximum near E_n = 0.23 MeV, also observed in the (n, α) cross section. At higher energies the total cross section shows broad maxima at E_n = 1.9, 2.8 and 4.3 MeV: see 11.28 (in PDF or PS). In the range E_n = 5.5 to 16 MeV σ_tot is constant at 1.5 b.

Elastic and inelastic cross sections have also been reported at E_n = 4 to 17 MeV [see (1980AJ01, 1990AJ01)], and at E_n = 3.0 to 12.0 MeV (1990SA24). Inelastic scattering cross sections for formation of the first five states of ¹⁰B have been measured in the range E_n = 3.0 to 12 MeV (1990SA24); twelve levels in ¹¹B above E_x = 13 MeV were identified. See 11.27 (in PDF or PS) for the R-matrix analysis of (n, n_0-5) and (n, n_α₀₊₁) data given in (1990SA24). The yield of 0.7 MeV γ-rays has been studied from threshold to E_n = 5.2 MeV: observed resonances are displayed in 11.28 (in PDF or PS). See 11.13 (in PDF or PS) in (1980AJ01) for an R-matrix analysis of cross section and analyzing power measurements from E_n = 0.075 to 4.4 MeV, and see (1975AJ02) for an analysis of measurements from E_n = 1.45 to 14.8 MeV. See also ¹⁰B in (1988AJ01).

See (2008MU23) for an analysis of the E_n < 2 MeV ¹⁰B(n, n) International Cross Section Standard: (1996CH33) for an optical model analysis of elastic scattering up to E_n = 200 MeV: and (2001AB14) for measurements at E_n ≤ 600 MeV. See (2008GE04) for an analysis on Mott-Schwinger scattering of E = 0 to 25 meV neutrons.

24. (a) ¹⁰B(n, p)¹⁰Be Q_m = 0.2256 E_b = 11.4541
(b) ¹⁰B(n, t)⁴He⁴He Q_m = 0.3224

The thermal cross section for reaction (a) is 6.4 ± 0.5 mb (1987LA16); that for reaction (b) is reported as σ = 4.47 ± 0.15 mb (1989CL01: see also for other references) and σ = 7 ± 2 mb (1987KA32). For reaction (a), differential cross sections were measured for E_n = 70 to 240 MeV (2007SO06); the stretched transition to ¹⁰Be_g.s. was studied in a DWIA analysis. The cross section for reaction (b) has also been studied for E_n = 1.4 to 8.2 MeV [see 11.28 (in PDF or PS) and (1968AJ02)] and 3 to 8 MeV (1986QA01). For various breakup processes see (1984TU02). For a display of cross sections and a listing of measurements see (1988MCZT).

See (1997BRZV) for a measurement of the total ¹⁰B(n, X) cross section for E_n = 0.08 to 2000 keV. Also see (2008MU23).

25. ¹⁰B(n, α)⁷Li Q_m = 2.7900 E_b = 11.4541

The "recommended" value of the thermal isotopic absorption cross section is 3837 ± 9 b (1981MUZQ, 2006MUZX). Also see σ = 3820 ± 135 b (2003MOZU). The k₀ factor for prompt 478 keV γ-rays from thermal neutron activation was measured in (2001AC04, 2003CHZX, 2004MA76).

The cross section for this reaction has been measured for E_n = 4.17 to 6.52 MeV (2002ZH35), E_n = 1.5 to 5.6 MeV (2005GI03, 2006GI03), E_n = 4.0 and 5.0 MeV (2008ZH20) and for E_n = 0.025 eV to 14.8 MeV [see (1975AJ02, 1980AJ01, 1985AJ01)]: for observed and deduced structures see 11.27 (in PDF or PS) and 11.28 (in PDF or PS). A study of the reaction involving polarized thermal neutrons and a polarized ¹⁰B target shows that the transition to ⁷Li*(0.48) proceeds almost totally through the J = 7/2 channel (1986KO19). For a display of cross sections and a listing of measurements see (1988MCZT). For a review see (1986CA28). "Detailed balance" [from ⁷Li(α, n) measurements] has led to the determination of the ¹⁰B(n, α₀) cross section from 0 < E_n ≤ 0.78 MeV: two resonances are inferred at E_R = 241 ± 18 and 493 ± 4 keV, with σ_R = 17 ± 3 and 112 ± 3 mb and Γ = 166 ± 40 and 194 ± 6 keV (1984OL05). Also see (2008LA18) for an indirect determination of the astrophysical S-factor via ²H(¹⁰B, pα) at E(¹⁰B) = 27 MeV.

The α₀/α₁ branching for thermal neutrons is (6.723 ± 0.011)% [mean of values listed in (1985AJ01)]. At E_n = 2 and 24 keV the α₀/α₁ ratios are (7.05 ± 0.16)% and (7.13 ± 0.15)%, respectively (1979ST03). At E_n = thermal to 5.5 keV, ratio values are reported near 6.7 ± 0.3 % (2000GO03). The ratio is reported for E_n = 0.1 keV to 1 MeV (2002HAZP, 2007HA06), E_n = 0.1 to 2 MeV (2009HA19), E_n = 20 keV to 1 MeV (1991WE11) and E_n = 0.2 to 0.4 MeV (1993SC20). Sizeable discrepancies between the data and the ENDF/B-VII library exist above 1 MeV.

The ratio of the ¹⁰B(n, α) cross section to the ⁶Li(n, t) cross section has been measured from E_n ≈ 1 to 45 eV (1986CA29), and E_n < 1 MeV (2008CA28).

Parity violation has been studied using polarized thermal neutrons: the P-odd asymmetries for the transitions to ⁷Li*(0, 0.48) are < 3.7 × 10^-6 (1986ER05) and +(0.0 ± 2.6 (stat.) ± 1.1 (sys.)) × 10^-8 (2011VE06), respectively: see also (1983VE10, 1994GL07, 1996VE02, 1999VE03, 2002VEZY, 2003VE10, 2005GI03, 2007NI05), and (1985AJ01) for the earlier work. See also ⁷Li in (1988AJ01).

The T-odd asymmetry parameter, related to time reversal invariance, is discussed in (2000GA43, 2003BA36, 2007NI05); an upper limit of 3.2 × 10^-4 is deduced from analysis of ¹⁰B(pol. n, αγ) at thermal energies (2000GA43).

Techniques of boron trace composition analysis are developed in (1994SA72, 1997SA70, 1998MA61).

26. ¹⁰B(p, π⁺)¹¹B Q_m = -128.8984

Angular distributions have been obtained at E_p = 168 to 800 MeV to several states of ¹¹B [see (1980AJ01, 1985AJ01)] as have cross sections for π⁺ production near threshold. At E_{pol. p} = 200 to 260 MeV, angular distributions and analyzing powers have been measured for the groups to ¹¹B*(0, 2.12) (1985ZI04). Angular distributions of pions have been measured at E_p = 209, 247 and 364 MeV (1995BB15).

27. ¹⁰B(d, p)¹¹B Q_m = 9.2296

Reported proton groups are displayed in 11.14 (in PDF or PS) of (1980AJ01). Angular distributions have been studied at energies in the range E_d = 0.17 to 28 MeV [see (1968AJ02, 1975AJ02, 1980AJ01)]. 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, 9.27) [J^π = 7/2⁺, 5/2⁺] 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. At E_d = 15.3 MeV, differential cross sections were measured for (d, p₂γ) to obtain the spin-tensor components of the density matrix (2005GA59); neutron stripping appears to be the dominant mechanism. Deformation parameters β₂(¹⁰B) = -0.55 and β₂(¹¹B) = 0.4 were deduced. A survey of ground state neutron spectroscopic parameters is given in (2005NI24, 2005TS03). Other studies of pγ correlations are discussed in reaction 14 of (1968AJ02) and displayed here in 11.19 (in PDF or PS). See also ¹²C.

Astrophysical S-factors are deduced from measurements at E_d = 60 to 140 keV (1993CE02, 1997YA02, 1997YA08), at E_d = 100 to 300 keV (2004RU10), and at E_d = 120 to 340 keV (2001HO22). At E_d < 3 MeV the p₀-p₃ reaction cross sections were analyzed to evaluate the impact of the ¹²C GDR and GQR on the astrophysical rates (2005RU16). At E_d = 900 to 2000 keV angular distributions and differential cross sections were measured for p₀-p₆, motivated mainly by boron composition depth profiling studies (2007KO69).

28. (a) ¹⁰B(t, d)¹¹B Q_m = 5.1969
(b) ¹⁰B(α, ³He)¹¹B Q_m = -9.1235

See (1968AJ02, 1975AJ02).

29. (a) ¹⁰B(⁷Li, ⁶Li)¹¹B Q_m = 4.2030
(b) ¹⁰B(⁹Be, ⁸Be)¹¹B Q_m = 9.7896
(c) ¹⁰B(¹³C, ¹²C)¹¹B Q_m = 6.5078

Optical potentials for reaction (a) are deduced in (2009RO10). For other work see (1980AJ01, 1985AJ01).

30. ¹¹Be(β^-)¹¹B Q_m = 11.5092

¹¹Be decays to many states of ¹¹B (1982MI08): see 11.29 (in PDF or PS) for the observed β- and γ-transitions. ¹¹B*(9.88) decays via α-emission to ⁷Li*(0, 0.48) with branching ratios (87.4 ± 1.2)% and (12.6 ± 1.2)%, respectively (1981AL03). A study of the βν angular correlation in the first-forbidden decay of ¹¹Be to the J^π = 1/2^- state ¹¹B*(2.12) has been performed; the β-transition is dominated by rank-0 matrix elements and is of interest as a test of meson-exchange effects: see (1982WA18, 1994WA01). See (1992HE12) who propose first forbidden β-decay as a probe of T-odd forces, and see (1993HA29) for discussion on β-decay isospin mixing probabilities and the ¹¹Be nuclear halo.

31. (a) ¹¹B(γ, n)¹⁰B Q_m = -11.4541
(b) ¹¹B(γ, p)¹⁰Be Q_m = -11.2285
(c) ¹¹B(γ, d)⁹Be Q_m = -15.8162
(d) ¹¹B(γ, t)⁸Be Q_m = -11.2235

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)]. Absolute measurements of the ¹¹B(γ, all n) cross section have been carried out from threshold to 35 MeV: the cross section exhibits a main peak at E_γ = 25 to 28 MeV and weak shoulders at 13 and 16 MeV. The integrated cross section up to 35 MeV is 69.1 ± 0.8 MeV ⋅ mb: see (1980AJ01) and (1988DI02). See also (1984AL22). For other structures reported in the (γ, n) and (γ, p) cross sections see (1975AJ02). The yield of 3.37 MeV γ-rays [from ¹⁰Be*(3.37), reaction (b)] has been measured for E_brem = 100 to 800 MeV. See also (1984AL22, 1986AL24). The (γ, d₀) cross section peaks at ≈ 19 MeV, lower than it would be expected to if T = 3/2 states were involved. For reaction (d) see (1986AL24). See (1980AJ01, 1985AJ01) for references and for other photonuclear processes.

Measurements at higher energies are reported for E_γ = 4.5 GeV (1990AR14) and for E_γ = 30 to 1200 MeV (1999SA08).

32. ¹¹B(γ, γ)¹¹B

Widths of excited states are displayed in 11.30 (in PDF or PS). The mixing ratios measured in (2009RU04) are displayed in 11.31 (in PDF or PS). See also (2000KA08, 2000ZI04).

33. (a) ¹¹B(e, e)¹¹B
(b) ¹¹B(e, ep)¹⁰Be Q_m = -11.2285

〈 r² 〉^1/2 = 2.43 ± 0.11 fm (1986DO1E).

[See also unpublished result in (1980AJ01).]

Magnetic elastic scattering at θ = 180° shows strong M3 effects: the derived ratio of static M3/M1, 2.9 ± 0.2 fm², suggests a j-j coupling scheme for ¹¹B_g.s.. The quadrupole contribution to the elastic form factor is best accounted for by the undeformed shell model, Q = 3.72(± 20%) fm², 〈 r² 〉^1/2 = 2.42 fm. See (1980AJ01) for references. A study of the elastic scattering for q = 2.0 to 3.9 fm^-1 is reported by (1988HI02): the M3 component is dominant in the elastic form factor for q > 1.5 fm^-1. See also (1994AM01, 1994BO04).

The excitation of ¹¹B*(2.1, 4.4, 5.0, 8.6, 8.9) has been studied. 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. At E_e = 121, 186 and 250 MeV form factors (and B(Eλ)↑) are obtained for ¹¹B*(4.4, 6.7, 8.5, 8.9, 13.00 ± 0.15) and the excitation of ¹¹B*(14.50 ± 0.15, 16.7 ± 0.2) is also reported: see (1985AJ01). See also (1994MO19).

For Γ_γ₀ see 11.30 (in PDF or PS). For reaction (b) see (1975AJ02).

34. ¹¹B(π⁺, π⁺)¹¹B

The proton matter distribution in ¹¹B_g.s. has a radius of 2.368 ± 0.021 fm, assuming that for ¹²C to be 2.44 fm. The result is not sensitive to the details of the optical-model calculations (1980BA45: E_π⁺ = 38.6 and 47.7 MeV).

35. ¹¹B(n, n)¹¹B

Angular distributions have been reported for E_n = 75 keV to 14.1 MeV [see (1980AJ01, 1985AJ01)] and at E_n = 8.0 to 13.9 MeV (1982GL02; n₀ → n₃). Other work is reported for E_n ≤ 17 MeV (1986MU08; n₀). See (1995XI06) for analysis of E_n = 7.54 to 20 MeV, (2000ZHZR) for E_n < 20 MeV, and (1996CH33) for E_n < 200 MeV. A measurement of the total cross section for ¹¹B(n, X) at E_n ≤ 600 MeV is given in (2001AB14). See an analysis of Mott-Schwinger scattering of E_n < 25 meV in (2008GE04). See also ¹²B.

36. (a) ¹¹B(p, p)¹¹B
(b) ¹¹B(p, 2p)¹⁰Be Q_m = -11.2285
(c) ¹¹B(p, pn)¹⁰B Q_m = -11.4541

Observed proton groups for reaction (a) are displayed in 11.32 (in PDF or PS). Angular distributions have been measured for E_p = 6 to 185 MeV [see (1980AJ01)], E_p = 0.5 to 3.3 MeV (2001CH78), E_p = 0.6 to 1.2 MeV (2011AM02), E_p = 1.7 to 2.7 MeV (1998MA54), E_p = 10 to 17 MeV (1986MU08), E_p = 392 MeV (2004KA53, 2004KA56) and at E_p = 1 GeV (1985AL16). Spin-isovector M1 strengths are given in (2003HA11) for excitation of the first three states with E_{pol. p} = 150 MeV. Polarization transfer coefficients for p₀ and p₃ were measured at E_p = 150 MeV (2003HA12). At E_p = 2.2 to 4.2 MeV and θ = 135° to 160°, proton elastic scattering cross sections were measured to evaluate the suitability of the reaction for boron depth profiling (2010KO33). At E_p = 3.2 to 3.6 MeV, thick target γ-ray yields were measured for PIGE analysis (1990BO15). Also see (1998DO16). For reactions (b) and (c) at E_p = 392 MeV see (2005NO13) and at E_p = 1 GeV see (1985BE30, 1985DO16). For pion production see (1988AB05). See also ¹²C, and (1985AJ01).

37. ¹¹B(d, d)¹¹B

Elastic scattering has been studied at E_d = 5.5 and 11.8 MeV: see (1980AJ01). At E_d = 200 MeV, angular distributions were measured for ¹¹B*(2.12, 4.44, 5.05, 6.74, 8.56, (8.92)) (2004KA53, 2007KA17, 2007KA49). Isoscalar M1 spin-flip strengths, B(σ), were derived (2004KA53), and isoscalar monopole and quadrupole strengths were deduced (2007KA17): see 11.33 (in PDF or PS). The large monopole strength for E_x = 8.56 MeV is interpreted as evidence for a developed 2α + t cluster structure. See (2011DE17) for a discussion of the radius of the ¹¹B*(8.56) state, and a comparison with the ¹²C*(7.65) Hoyle state.

38. ¹¹B(t, t)¹¹B

The elastic scattering has been studied at E_t = 1.8 and 2.1 MeV: see (1980AJ01).

39. ¹¹B(³He, ³He)¹¹B

The elastic scattering has been studied at E(³He) = 8 to 74 MeV: see (1975AJ02, 1980AJ01). At E(³He) = 17.5 and 40 MeV angular distributions have been studied for the ³He ions to ¹¹B*(2.12, 4.44, 5.02, 6.74). T = 3/2 states observed in this reaction are displayed in 11.34 (in PDF or PS). See also (1985AJ01). There is a weak indication of a state at E_x = 14.51 MeV: see (1975AJ02).

40. ¹¹B(α, α)¹¹B

Angular distributions have been reported at E_α = 24 to 54.1 MeV [see (1975AJ02, 1980AJ01, 1985AJ01, 1990AJ01)]. A review of α-particle scattering cross sections for E_α = 2 to 8 MeV is given in (1991LE33). Elastic and inelastic scattering were measured at E_α = 40 and 50 MeV (2005BU33); optical model, β₂ and β₄ deformation parameters were deduced. A DWBA analysis of data taken at E_α = 388 MeV is given in (2010KAZZ). Depth profile studies on boron-doped materials have been carried at E_α = 3.5 to 7.5 MeV (1990MO21) and at E_α = 1.0 to 5.3 MeV (1996LI62, 1996ZH36).

41. ¹¹B(α, ⁷Li) Q_m = -8.7559

Cluster configuration spectroscopic factors are deduced (1995BO31) at E_α = 27.2 MeV.

42. (a) ¹¹B(⁶Li, ⁶Li)¹¹B
(b) ¹¹B(⁷Li, ⁷Li)¹¹B

The elastic scattering has been studied at E(⁶Li) = 28 MeV: see (1975AJ02). At E(⁷Li) = 34 MeV angular distributions have been reported to ¹¹B*(0, 2.12, 4.44, 5.02, 6.74, 7.29, 8.92) (1987CO02, 1987CO16); also see (2005RU17, 2005RU18). At E(¹¹B) = 44 MeV, scattering on a ⁷Li target populated ¹¹B*(0, 2.12, 4.44, 5.02, 6.74, 7.29, 7.98, 8.56, 8.92) (2005RU18). Deformation parameters were deduced for ⁷Li and ¹¹B states, and contributions from 1- and 2-step cluster transfers are found to be small in both the elastic and inelastic channels.

43. (a) ¹¹B(⁹Be, ⁹Be)¹¹B
(b) ¹¹B(¹⁰B, ¹⁰B)¹¹B
(c) ¹¹B(¹¹B, ¹¹B)¹¹B

For reaction (a) see (1984DA17, 1986CU02). For fusion cross sections (reactions (b) and (c)) see (1989SZ01). See also (1975AJ02, 1980AJ01).

44. (a) ¹¹B(¹²C, ¹²C)¹¹B
(b) ¹¹B(¹³C, ¹³C)¹¹B

The elastic scattering has been studied at E(¹¹B) = 18.8 to 50 MeV and at E(¹²C) = 15 to 24 MeV and 87 MeV [see (1980AJ01, 1985AJ01)] as well as at E(¹¹B) = 10.4, 12.4 and 14.6 MeV (1985JA01), at E_cm = 25 MeV (1986MA13), at E(¹¹B) = 42.5 to 100 MeV (1985MA10) and at E(¹²C) = 65 MeV (1985GO1H) [see ¹²C]. The population of ¹¹B*(2.12, 4.44, 6.79) is reported. For yields, fusion and breakup studies see (1985AJ01) and (1985MA10, 1986MA13). For reaction (b) see (1984DEZX, 1984HAZK).

45. ¹¹B(¹⁴N, ¹⁴N)¹¹B

The elastic scattering has been investigated at E(¹⁴N) = 41, 77 and 133 MeV: see (1975AJ02, 1985AJ01).

46. (a) ¹¹B(¹⁶O, ¹⁶O)¹¹B
(b) ¹¹B(¹⁷O, ¹⁷O)¹¹B
(c) ¹¹B(¹⁸O, ¹⁸O)¹¹B

The elastic scattering in reaction (a) has been studied at E(¹⁶O) = 14.5 to 60 MeV and at E(¹¹B) = 41.6, 49.5 and 115 MeV; for references see (1975AJ02, 1980AJ01, 1985AJ01). Elastic and quasi-elastic scattering are reported in (1994AN05: E(¹⁶O) = 22 to 64 MeV). Also see (1992KA19).

For reaction (b) see (1994AN05). For reaction (c), elastic and quasi-elastic scattering are reported at E_cm = 18.8 and 19.9 MeV (1992LE04), at E(¹⁸O) = 22 to 64 MeV (1994AN05), and at E(¹¹B) = 115 MeV (1980PR09; elastic). Analysis in (1992LE04) evaluated evidence for long-lived orbiting phenomena in the compound system.

47. ¹¹B(²⁰Ne, ²⁰Ne)¹¹B

The elastic angular distribution has been studied at E(¹¹B) = 115 MeV: see (1985AJ01).

48. (a) ¹¹B(²⁴Mg, ²⁴Mg)¹¹B
(b) ¹¹B(²⁵Mg, ²⁵Mg)¹¹B
(c) ¹¹B(²⁶Mg, ²⁶Mg)¹¹B
(d) ¹¹B(²⁷Al, ²⁷Al)¹¹B
(e) ¹¹B(²⁸Si, ²⁸Si)¹¹B

The elastic angular distributions for reactions (a) to (d) have been studied at E(¹¹B) = 79.6 MeV: see (1985AJ01). See also (1987PO15). For reaction (e) see (1984TE1A).

49. (a) ¹¹B(⁴⁰Ar, ⁴⁰Ar)¹¹B
(b) ¹¹B(⁴⁰Ca, ⁴⁰Ca)¹¹B

For reaction (a) at E(⁴⁰Ar) = 7 MeV/A see (1986MO15). Angular distributions have been reported in reaction (b) at E(¹¹B) = 51.5 MeV to ¹¹B*(0, 2.12): see (1985AJ01).

50. ¹¹C(β⁺)¹¹B Q_m = 1.9824

The β⁺-decay of ¹¹C populates ¹¹B_g.s.; see ¹¹C. A 4π-β-γ coincidence system to evaluate the activity of ¹¹C sources is discussed in (2004NI04).

51. ¹²C(γ, p)¹¹B Q_m = -15.9569

Angular distributions to the ground and to excited states of ¹¹B (and to ¹¹C states reached in the (γ, n) reaction) have been measured at various energies (see 11.35 (in PDF or PS)); the ground state is predominantly populated: see measurements and discussion in (1980AJ01, 1985AJ01, 1990AJ01) and (1986AN25, 1986MC15, 1990SP06, 1990VA07, 1990VA09, 1991IS09, 1993IR01, 1994NI04, 1994ZO01, 1995HA03, 1996RU15, 1997AS01, 1997ZO02, 1998KU23, 1998SO18, 2001ME29). Analog states are populated similarly in the (γ, n) and (γ, p) reactions. Also see (2000DE58).

Bremsstrahlung photons at E_γ = 50 to 70 MeV (tagged) were used to study ¹²C(γ, pγ')¹¹B; states at ¹¹B*(2.12, 4.45, 5.02, 6.74, 6.79, 7.29) were resolved. The analysis centered on the mechanism for populating the ≈ 7 MeV triplet states (1998KU23). The relative population of ¹¹B*(6.8) is much greater than that reported in (e, ep) (1988SH08). The role of different reaction mechanisms, including quasi-deuteron knockout, is investigated in (1990VA07, 1992RY02, 1992VA01, 1993HA12, 1993IR01, 1994NI04, 1995MO18, 1996AS02, 1996JO15, 1996RU15, 1997AS01, 1997JO07, 2000LE38, 2002ME17, 2005KA54).

Reactions in the "Delta" resonance region are discussed in (1992BA57, 1992GL04, 1995CR04, 1997JO07, 2000GL08, 2001MA31, 2002ME17, 2006AN22). In this region peaks corresponding to removal of s-shell and p-shell protons are observed in the missing mass spectrum, and quasi-free photo pion production is an important reaction mechanism. Evidence for η-mesic ¹¹B atoms is claimed in (1999SO18, 2000SO19, 2002BA21); also see (1995LE26, 1999LE35, 1999TR09, 2003HE18, 2005NA17, 2005NA25, 2005NA35, 2006NA34, 2008JI06).

52. ¹²C(ν, p) Q_m = -15.9569

Neutrino induced proton knockout reactions on ¹²C are discussed in (1995UM02, 1995UM03, 2003KO50, 2008MA21, 2008ME03). Sensitivity to the strange quark content of the nucleon is given in (1993GA20, 2004ME18, 2004VA09, 2006LA13, 2006ME17, 2006ME24, 2006MA67). Enhancement of ¹¹B production in supernovae explosions is discussed in (2006SU15, 2007SU08).

53. ¹²C(e, e'p)¹¹B Q_m = -15.9569

Measurements reported at E_e = 21 MeV to 14.5 GeV are listed in 11.36 (in PDF or PS). Levels at ¹¹B*(0, 2.12, 4.44, 5.02, 6.74, 6.79, 7.28) are populated; see discussion in (1985VA16, 1988VA09, 1988VA21, 1990DE16, 1992BO10, 1994CA08, 1994IR01, 1994TA11, 1996KE03). ¹¹B*(0, 2.12, 5.02) are populated by l = 1 knockout (1988VA09). The relative population of ¹¹B*(6.8) is much less than that reported in (γ, p) (1988SH08). A high-resolution measurement reported in (1988VA21) observed weak transitions to 8.61 ± 0.05, 9.820 ± 0.025 MeV and to a broad structure at 11.5 MeV. l = 0 and 1 are suggested for the structures at 9.8 and 11.5 MeV. A structure at ≈ 12 MeV is reported in (1996KE03). One-third to one-half of the sum-rule strength predicted by the independent-particle shell model is observed (1988VA09). Weak population of ¹¹B*(4.44) by (1992BO10) is interpreted as arising almost completely from two-step processes.

Spectroscopic factors for 1s and 1p shell single-particle knockout reactions are discussed in (1990CA14, 1990DE16, 1990WE06, 1991WE10, 1991WE16, 1994IR01, 1994IR02, 1995BL10, 1995KE03, 1998WO01, 1999DO30, 1999RY06, 2000DU12, 2000LA23, 2002MA12). Effects such as transparency of the nuclear medium have been studied by (1990FR11, 1992BE23, 1992FR17, 1992GA02, 1992JE03, 1992PA03, 1993LO01, 1993NI11, 1994FR12, 1994FR16, 1994GR05, 1994IR02, 1994MA23, 1994NI05, 1995FR04, 1996KE14, 1996NI13, 1997IW03, 1999RY06, 2000DU12, 2000LA23, 2001FR06, 2002DE11, 2002GA43, 2002ME17, 2003DU23, 2003RY02, 2004LA13, 2004BA99, 2005RO38, 2006RO37). Discussion on other final state interactions is given in (1991CA09, 1994IR02, 1994JE04, 1994RY04, 1995BI07, 1995BI19, 1995NI02, 1996BI01, 1996BI21, 1996JE04, 1999KE04, 2002DE07, 2004BA99, 2004BB15, 2005BA23, 2007PI05), and discussion on the reaction mechanism influence is found in (1990LO09, 1991VA05, 1992DR02, 1993CI05, 1993OF01, 1994IR01, 1994RY03, 1994TA11, 1994WE06, 1999MO02, 2002ME17, 2004FR27, 2004MU29, 2004RO35, 2004TA18, 2011RY03). See also (1993KE02, 1994BI05, 1994VE08, 1994WA19, 1995RY02, 1997BI06, 1997GI13, 1998HO20, 2000DE38, 2000UD01, 2005KE04).

The production of ¹¹B in astrophysical sites with large densities of high-energy electrons is discussed by (1983HO15).

54. (a) ¹²C(π⁺, π⁺p)¹¹B Q_m = -15.9569
(b) ¹²C(π^-, π^-p)¹¹B Q_m = -15.9569

At E_π⁺ = 100 to 200 MeV the reaction proceeds primarily to ¹¹B_g.s.. At E_π = 200 MeV the ratios for σ_n/σ_p for the first excited states in ¹¹C/¹¹B(J^π = 1/2^-₁) are 1.4 ± 0.2 for π^- and 1/1.8 ± 0.2 for π⁺. At E_π⁺ = 60 to 300 MeV ¹¹B*(4.44) [J^π = 5/2^-] is strongly populated as is the analog state in the mirror reaction: see (1980AJ01, 1985AJ01) for references. At E_π^± = 220 MeV the quasi-elastic nature of the scattering has been studied by (1984FA11). The proton Fermi-momentum distributions were analyzed at E_π^- = 0.7, 0.9 and 1.25 GeV/c (2000AB25). See also the studies by (1984ZI1B, 1987HU02, 1991BE43), ¹²C.

55. ¹²C(n, d)¹¹B Q_m = -13.7323

See (1994MO41) and ¹³C in (1986AJ01, 1991AJ01).

56. ¹²C(p, 2p)¹¹B Q_m = -15.9569

An overview of ¹²C(p, 2p) measurements is given in 11.37 (in PDF or PS). At E_p = 98.7 MeV groups are observed to ¹¹B*(0, 2.12, 4.44, 5.02, 6.79); DWIA lead to relative spectroscopic factors of 2.0, 0.37, 0.15, 1.08, 0.25 for these states. No evidence is seen for multistep reaction processes which would be necessary to populate ¹¹B*(4.44, 6.74): see (1979DE35). At E_p = 392 MeV (2003YO01) states at E_x ≈ 8.5 and ≈ 10 MeV are also observed in addition to the s-hole state in ¹¹B, which is split into three different components with E_x = 16.1 ± 0.1 MeV (Γ = 5.3 ± 0.3 MeV), E_x = 21.9 ± 0.2 MeV (Γ = 8.1 ± 0.2 MeV) and E_x = 28.7 ± 0.7 MeV (Γ = 9.7 ± 2.5 MeV); also see (2001YA08, 2004YA20, 2004YO06, 2004YO08); see additional discussion on knockout spectroscopic factors in (2002BR26, 2011SI01).

At E_p = 1 GeV the separation energy between 6 and 14 MeV broad 1p_3/2 and 1s_1/2 groups is 18 MeV (1985BE30, 1985DO16); also see (1967GO01, 1969JA05, 1970SI01, 1971LA16, 1976BH02, 2004AN01, 2008KO12, 2008NO01; exp.) and (1990LO18, 1995GA46, 2003TA03, 2006HI15; theor.). Initial and finial state effects, such as color transparency and nuclear modifications to the NN interaction are discussed in (1966TY01, 1978KO30, 1979JA20, 1988CO02, 1989CO17, 1989PI12, 1997HA15, 1998MA67, 1998NO04, 1999AC03, 1999CA11, 1999CA15, 2000NO03, 2003TA03, 2004AC08; exp.) and (1992LE03, 1994FR12, 1994FR16, 1994KO21, 1997GA16, 2000ST17, 2002DI04, 2004AC08, 2006DA15, 2006VA08, 2007DA19, 2007RY02, 2009CO10; theor.).

57. ¹²C(p, dπ⁺) Q_m = -154.0849

Measurements were performed at E_p = 223 MeV (1992CO04) and E_p = 370 and 500 MeV (1998BE38). Population of ¹¹B*(0, 2.12, 5.02) and continuum excitations near 20 MeV, interpreted as 1s_1/2 hole excitations, were observed (1998BE38); spectroscopic factors were also deduced.

58. ¹²C(d, ³He)¹¹B Q_m = -10.4634

Angular distributions of ³He ions have been measured for E_d = 20 to 80 MeV and spectroscopic factors have been derived for ¹¹B*(0, 2.12, 5.02): see references in (1975AJ02, 1980AJ01, 1985AJ01). The ¹²B spin dipole resonance is studied via ¹²C(d, ²He + n) at E_d = 171 MeV (2007DE28). Also see (2001KR01).

59. ¹²C (t, α)¹¹B Q_m = 3.8570

Angular distributions have been measured at E_t = 33 MeV (1987FO21, 1991PI09) and 38 MeV (1988SI08) to ¹¹B*(0, 2.12, 4.44, 5.02, 6.74, 7.29, 7.98, 8.56); spectroscopic factors are deduced. As expected, the J^π = 5/2^- and 7/2^- states ¹¹B*(4.44, 6.74) are populated by two-step processes. The best J^π value for ¹¹B*(8.56) is 3/2^- but this assumes some direct population which may not be the case. For the earlier work at E_t = 1 to 3.4, 10.1 and 13 MeV see (1975AJ02).

60. ¹²C(α,⁵Li)¹¹B Q_m = -17.9219

See (1987GA20) and (1985AJ01).

61. (a) ¹²C(⁶He, ⁷Li)¹¹B Q_m = -5.9822
(b) ¹²C(⁶Li, ⁷Be)¹¹B Q_m = -10.3500

The ⁷Li_g.s. angular distribution was measured for reaction (a) at E(⁶He) = 36.4 MeV. A DWBA analysis reproduces the data (2009LI27).

Reaction (b) was measured at E(⁶Li) = 93 MeV; ¹¹B*(0, 2.12, 5.0, 6.8, 8.9) are populated (1988BUZI). Polarization observables were measured at E(⁶Li) = 50 MeV (1997KE04).

62. ¹²C(¹⁰Be, ⁷Li + α) Q_m = -13.3925

Peaks corresponding to ¹¹B*(9.3 ± 0.1 and 10.3 ± 0.1 MeV) are observed in the kinematic energy spectrum of ⁷Li_g.s. + α particles following ¹²C + ¹⁰Be reactions at E(¹⁰Be) = 302 MeV (2004AH02, 2004AH06). The measurement could not resolve possible participation of ⁷Li*(0.48).

63. (a) ¹²C(¹¹B, ¹¹B)
(b) ¹²C(¹¹B, ⁷Li + α)

Angular distributions for elastic and inelastic scattering are reported for E(¹¹B) = 49 MeV ¹¹B*(0, 2.12, 4.45 + ¹²C(2⁺), 5.02) (2001RU14, 2003ME36), E_cm = 15 to 40 MeV ¹¹B*(0, 2.12, 4.45) (1991JA09), and E(¹¹B) = 344.5 MeV ¹¹B*(0, 4.45) (1992JA12). Optical model parameters and spectroscopic factors are deduced. Quadrupole deformation parameters of δ₂ = 1.0 and 0.8 fm are deduced for ¹¹B*(0, 5.02), respectively (2003ME36).

For reaction (b) at E(¹¹B) = 87 MeV, ¹¹B*(9.19, 9.27, 10.27, 10.61) states were observed at E_rel = 527 ± 10 keV, 604 ± 10 keV, 1610 ± 14 keV and 1948 ± 7 keV with measured widths of Γ = 30 ± 11, 37 ± 9, 337 ± 44 and 83 ± 22 keV, respectively (1994WO02). The broad widths of the first two levels are explained with the ≈ 41 keV energy resolution.

The measured interaction cross section for ¹¹B + ¹²C at E(¹¹B) = 950 MeV is 778 ± 30 mb; this implies R_rms^matter = 2.09 ± 0.12 fm (2001OZ03, 2001OZ04).

64. ¹²C(¹²C, X)

At E(¹²C) = 344.5 MeV angular distributions and spectroscopic factors involving ¹¹B*(0, 2.12) are reported in (1992JA10). Angular distributions involving ¹¹B_g.s. are reported in (1979FU04: E(¹²C) = 93.8 MeV) and (1974AN36: E(¹²C) = 114 MeV). See also (1995HO02).

65. ¹²C(¹³C, ¹⁴N)¹¹B Q_m = -8.4063

See (1987AD07, 1988VO08) and ¹⁴N in (1991AJ01).

66. ¹²C(¹⁹F, ²⁰Ne)¹¹B Q_m = -3.1134

At E(¹⁹F) = 40, 60 and 68.8 MeV angular distributions involving ¹¹B*(0, 2.12) and ²⁰Ne*(0, 1.63) have been measured: see (1980AJ01).

67. ¹³C(p,³He)¹¹B Q_m = -13.1852

At E_p = 50.5 MeV, in addition to ¹¹B*(0, 2.12, 4.44, 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 [to the analog state] 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: see 11.34 (in PDF or PS). Angular distributions have been measured at E_p = 26.9 to 49.6 MeV involving the above states except for ¹¹B*(8.92) and at E_{pol. p} = 65 MeV (to ¹¹B*(0, 2.12)): see (1975AJ02, 1980AJ01, 1985AJ01). See also ¹⁴N in (1986AJ01).

68. ¹³C(d, α)¹¹B Q_m = 5.1679

Observed α groups are displayed in 11.32 (in PDF or PS). Angular distributions are reported at E_d = 150 to 350 keV (1993MA45), E_d = 180 to 350 keV (1998NA38), E_d = 0.5 to 1.65 MeV (2007CO01), E_d = 15.3 MeV (2009GA19, 2010GA05), and E_d = 0.41 to 14.1 MeV; see references in (1975AJ02).

At E_d = 15.3 MeV analysis of the angular distributions indicates the 4.4 MeV J^π = 5/2^- state is mainly formed by deuteron pickup, while both deuteron pickup and ⁹Be cluster-exchange are important for ¹¹B*(0, 2.12, 5.02) (2009GA19). In (2010GA05) the measurements were extended to include double differential cross sections for detecting γ+α coincidences. The angular dependences of the even components of density matrix spin tensors, magnetic sublevel populations, and components of multipole moment orientation tensors of the ¹¹B nucleus were obtained and analyzed for ¹¹B*(4.45).

69. ¹³C(¹¹B, ¹¹B)

Scattering distributions for ¹¹B*(0, 2.125, 4.445, 5.020, 6.743 + 6.792, 7.286, 7.978, 8.560) and other ¹³C states were measured at E(¹¹B) = 45 MeV (2003ME13). The mechanism for anomalous large angle scattering was evaluated in Optical Model and Coupled Channels analyses.

70. ¹⁴C(p, α)¹¹B Q_m = -0.7840

Observed states are displayed in 11.32 (in PDF or PS) (1985AR03). It is suggested ¹¹B*(12.92, 15.29, 16.50, 19.07) are T = 3/2, negative-parity states. Spectroscopic factors have also been derived (1985AR03).

71. ¹⁴C(¹¹B, ¹¹B)

At E(¹¹B) = 45 MeV ¹¹B*(0, 2.12, 4.4, 5.02, 6.74 + 6.79, 7.28, 7.97, 8.56) are observed in the scattering reactions (2005ME05).

72. (a) ¹⁴N(n, α)¹¹B Q_m = -0.1581
(b) ¹⁴N(n, 2α)⁷Li Q_m = -8.8222

Angular distributions have been measured for E_n = 4.9 to 18.8 MeV [see (1975AJ02, 1980AJ01, 1985AJ01)], at E_n = 1.7 to 7 MeV (2011KHZW), at E_n = 5.46 to 7.2 MeV (2006KH12; α_0-3), and at E_n = 12.2, 14.1 and 18.0 MeV (1986RU1B; α₀, α₁). 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 = 7/2 and 5/2 for ¹¹B*(9.19, 9.27) respectively: see (1975AJ02). In (2006KH12) a comparison of the cross section with the ENDF/B VI values is given, and the impact of ¹⁴N in nuclear reactors is discussed.

73. ¹⁴N(p, p³He)¹¹B Q_m = -20.7357

See (1986VDZY; E_p = 50 MeV).

74. ¹⁶O(d, ⁷Be)¹¹B Q_m = -16.0382

At E_d = 80 MeV angular distributions have been measured to ¹¹B* (0, 2.12, 4.44 + 5.02, 6.74 + 6.79 + 7.29): see (1980AJ01).

75. ²⁰⁸Pb(¹¹B, ¹¹B')

Coulomb excitation of ¹¹B*(2.2) is discussed in (2007BE54).