
^{9}Be (1988AJ01)(See Energy Level Diagrams for ^{9}Be) GENERAL: See also (1984AJ01) and Table 9.2 [Table of Energy Levels] (in PDF or PS). Shell model: (1983VA31, 1984VA06, 1984ZW1A, 1985AN16, 1987KI1C, 1988OR1C, 1988WO04). Cluster and αparticle models: (1981PL1A, 1982DZ1A, 1983JA09, 1983MI1E, 1983SH38, 1985HA1P, 1985KW02, 1986CR1B, 1987VOZU). Special states: (1981PL1A, 1983AU1B, 1983GO28, 1983MI08, 1983VA31, 1984BA49, 1984KO40, 1984VA06, 1984WO09, 1984ZW1A, 1985GO1A, 1985HA1J, 1985PO19, 1985SH24, 1986AN07, 1986WI04, 1987KI1C, 1987VOZU, 1988KW02). Electromagnetic transitions and giant resonances: (1983GM1A, 1983MI08, 1984BA49, 1984MO1D, 1984VA06, 1985GO1A, 1986ER1A, 1986SC1F, 1987HO1L, 1987KI1C). Astrophysical questions: (1982AU1A, 1982CA1A, 1983SI1B, 1984TR1C, 1985MI1E, 1985WA1K, 1985WE1A, 1986BO1H, 1987AR1C, 1987AU1A, 1987DW1A, 1987MA2C, 1987RO25, 1988RE1B, 1988SA2H). Complex reactions involving ^{9}Be: (1983CH23, 1983EF1A, 1983EN04, 1983GU1A, 1983HA1C, 1983MA53, 1983NA08, 1983OL1A, 1983SO08, 1983ST1A, 1983VA23, 1983WA1F, 1983WI1A, 1984AI1A, 1984GR08, 1984HI1A, 1984IS02, 1984RE14, 1984SI15, 1984XI1B, 1985AG1A, 1985BA1V, 1985BH02, 1985FA02, 1985MA13, 1985MC03, 1985MO08, 1985MO17, 1985MO24, 1985PO11, 1985PO19, 1985RO10, 1985SH1G, 1985TR1B, 1985WA1F, 1985WA22, 1986AV1B, 1986BA2D, 1986BA2H, 1986BA1Q, 1986HA1B, 1986MA19, 1986MA1O, 1986ME06, 1986PO06, 1986RE13, 1986SA30, 1986SH1F, 1986SIZS, 1986SO10, 1986WA1H, 1986WE1C, 1987AK1A, 1987AR19, 1987AU1C, 1987BA38, 1987BO23, 1987DE37, 1987FA09, 1987FE1A, 1987GO17, 1987GR11, 1987HE1H, 1987JA06, 1987KIZY, 1987KO15, 1987KW02, 1987LY04, 1987MU03, 1987MU1D, 1987NA01, 1987PO03, 1987SH23, 1987SI1C, 1987SO13, 1987SO15, 1987ST01, 1987TAZU, 1987TR05, 1987VI14, 1987WA09, 1987YA16, 1987YI1A, 1988BL09, 1988CA06, 1988CH04, 1988GO1F, 1988KA1L, 1988KI05, 1988KR11, 1988POZZ, 1988PO1F, 1988RU01, 1988SA2H, 1988SA19, 1988SH1E, 1988TS03). Applications: (1983KU1C, 1984CA1D, 1984IM1A, 1987IN1A, 1987KU1L). Muon and neutrino capture and reactions: (1983GM1A, 1983GU10, 1984RO1B, 1987KU23, 1987SU06). Reactions involving pions (See also reactions 2 and 17.): (1983BU1D, 1983GE12, 1983GM1A, 1983HA45, 1983SH19, 1983SU08, 1983ZA1B, 1984BO1H, 1984HA1K, 1984LE11, 1985AR15, 1985BA1V, 1985LA20, 1985IM1A, 1985MA1G, 1985MO1F, 1985PN01, 1986CE04, 1986PE05, 1986RO03, 1986YA1D, 1986ZO1A, 1987AN14, 1987GOZN, 1987GO25, 1987GR1G, 1987MA1I, 1987PI1B, 1988BA82, 1988GIZU, 1988KA1N). Reactions involving kaons and other mesons: (1983BA71, 1983BR1E, 1983FE07, 1983GE13, 1983GE1C, 1983PO1D, 1983ZA1B, 1984BO1H, 1984MO09, 1985MO1F, 1985YA05, 1986AB07, 1986BA1W, 1986CH1P, 1986DO1B, 1986FI1A, 1986GA1H, 1986YA1D, 1986YA02, 1986ZO1A, 1987PI1B, 1987PO1H, 1987YA1I, 1988BA82, 1988MO1B, 1988KH03, 1988WA1B). Antinucleon reactions: (1987LE32, 1988KA1N). Hypernuclei: (1982DZ1A, 1982MO1B, 1983AU1A, 1983BA1M, 1983BA1D, 1983BR1E, 1983FE07, 1983KO1C, 1983MA64, 1983MI1E, 1983MO1C, 1983OR1A, 1983PO1D, 1983SH1E, 1983ZH1B, 1984BA1N, 1984BO1A, 1984BO1H, 1984CH1G, 1984CH1H, 1984DA1D, 1984JI05, 1984KO1B, 1984MI1C, 1984MI1E, 1984MO09, 1984MO1H, 1984SC1A, 1984ZH1B, 1985HA1P, 1985IK1A, 1985MO1F, 1985YA05, 1985YU1A, 1986BA1W, 1986BO1E, 1986CH1P, 1986DO1B, 1986ER1A, 1986GA1H, 1986MA1C, 1986MA1W, 1986ME1F, 1986PO1G, 1986SH1V, 1986WA1J, 1986YA1D, 1986YA1F, 1986YA02, 1986YU1A, 1987BA2K, 1987BO1L, 1987BO1O, 1987IK1B, 1987JI1A, 1987PI1C, 1987PO1H, 1987WA36, 1987YA1I, 1987YA1C, 1987YA1M, 1988BA82, 1988CH48, 1988HA44, 1988JI1A, 1988MA1G, 1988MO1B, 1988KH03, 1988TA29, 1988WA1B). Other topics: (1984CL11, 1984DA11, 1984PO11, 1985AN28, 1985AR1B, 1985EL1A, 1985KA01, 1985SH24, 1986BI01, 1986KU11, 1986IS04, 1986SA02, 1986SC1F, 1987KU1I, 1988KW02, 1988OR1C). Groundstate properties of ^{9}Be: (1983ANZQ, 1983AU1B, 1983KU06, 1983VA31, 1984AN1B, 1984BR25, 1984FR13, 1984MIZM, 1985AN16, 1985AN28, 1985BE59, 1985CL1A, 1985GO1A, 1985HA1P, 1985SA32, 1986CR1B, 1986JI01, 1986GL1A, 1986RO03, 1986SY1A, 1986WI04, 1987HA30, 1987KI1C, 1987LE33, 1987SA15, 1988JO1C, 1988VA03, 1988WO04).
Q = +(53 ± 3) mb: see (1978LEZA). The interaction nuclear radius of ^{9}Be is 2.45 ± 0.01 fm [(1985TA18); E = 790 MeV/A: see also for derived nuclear matter, charge and neutron matter r.m.s. radii]. The decay ^{9}Li_{Λ} → π^{} + ^{9}Be* → π^{} + p + ^{8}Li appears to take place via a T = 3/2 state of ^{9}Be at E_{x} = 18.6 ± 0.1 MeV (Γ ≤ 300 keV) (1985PN01).
The 0° differential cross section for reaction (a) increases monotonically between E_{t} = 0.10 and 2.4 MeV. A resonance has been reported at E_{t} = 1.875 MeV (^{9}Be*(18.94)). The excitation function for ^{8}Li (reaction (b)) increases monotonically for E_{t} = 0.275 to 1.000 MeV. See (1974AJ01) for references. In the range E_{t} = 2 to 10 MeV the total cross section for reaction (b) shows a broad structure [Γ_{c.m.} = 1.5 MeV] at E_{t} = 4.2 MeV (^{9}Be* = 20.5 MeV) (1986AB04; prelim.). Yields and angular distributions for reaction (c) have been measured at E_{t} = 2 to 4.5 MeV (1984LIZY; prelim.). See also (1984AJ01) for other channels and (1984KR1B; theor.).
The energy dependence of the π^{+} to ^{9}Be_{g.s.} has been measured at E(^{3}He) = 235 to 283 MeV (1984WI06).
Angular distributions of p_{0} have been measured at E_{α} = 10.2 to 14.7 MeV and at 30 MeV: see (1974AJ01). See also (1987BI1C) and (1983BE51; theor.).
For E_{d} = 0.1 to 1.1 MeV, a resonance in the yield of capture γrays is observed at E_{d} = 360.8 ± 0.3 keV (1987ZI01), 360.7 ± 1.8 keV (1986BE33), corresponding to the excitation of ^{9}Be*(16.97), the second T = 3/2 state [J^{π} = 1/2^{}]: see Table 9.4 (1987ZI01). The reduced width for the isospin "forbidden" deuteron breakup is 5.4 × 10^{4} relative to the Wigner limit (1987ZI01). See also (1984AJ01).
The yield of neutrons has been measured for E_{d} = 0.2 to 23 MeV [see (1979AJ01)] and at E_{d} = 0.19 to 0.55 MeV (1987DA25). See also (1983SZZY). Polarization measurements have been carried out at E_{d} = 0.64 MeV and 2.5 to 3.7 MeV [see (1974AJ01)] and at 0.40 and 0.46 MeV (1984GA07; n_{0}). Resonances are reported at 0.36, 0.68 and 0.98 MeV: see Table 9.3 (in PDF or PS) in (1974AJ01). See also (1985CA41; astrophys.). The yields of αparticles have been measured for E_{d} = 0.25 to 3.0 MeV: see (1974AJ01, 1979AJ01). Resonances are reported at E_{d} = 0.75, 1.00 and 2.5 MeV; the latter is broad: see Table 9.3 (in PDF or PS) in (1979AJ01). See also (1983SZZY), (1986DIZT, 1987LE1F; applied) and (1984KR1B; theor.).
Excitation functions and cross sections have been measured for E_{d} = 0.29 to 7 MeV [see (1974AJ01, 1979AJ01, 1984AJ01)] and 0.60 to 0.95 MeV (1983FI13). See also (1983SZZY, 1986AB04). Resonances are reported at E_{d} = 0.360(3) [< 0.5], 0.776(7) [250], 1.027(7) [60], 2.0 [broad], 2.375(50), 3.220(50) [400 ± 100] and ≈ 4.8 MeV [Γ_{lab} in keV] corresponding to ^{9}Be*(16.975 [see also Table 9.4 (in PDF or PS)], 17.298, 17.493, (18.5), 18.54, 19.20, 20.4): for references see Table 9.3 (in PDF or PS) in (1979AJ01) and Table 9.3 (in PDF or PS) in (1984AJ01). The total cross section at the E_{d} = 0.78 MeV resonance is important because it serves as normalization for the ^{7}Be (p, γ) ^{8}B reaction: the "best" value suggested by (1983FI13) is 157 ± 10 mb. See also (1986BA38) and (1974AJ01, 1984AJ01) for the earlier values. At E(^{7}Li) = 12.2 ± 1.3 MeV [corresponding to E_{d} = 3.5 MeV] the cross section is reported to be 155 ± 20 mb (1985HA40).
The elastic scattering [E_{d} = 0.4 to 1.8 MeV] shows a marked increase in cross section for E_{d} = 0.8 to 1.0 MeV (perhaps related to ^{9}Be*(17.30)) and a conspicuous anomaly at E_{d} = 1.0 MeV, due to pwave deuterons [^{9}Be*(17.50)]. The elastic scattering has also been studied for E_{d} = 1.0 to 2.6 MeV and 10.0 to 12.0 MeV: see (1979AJ01).
The cross section rises steeply from threshold to 95 mb at E_{d} = 2.4 MeV and then more slowly to ≈ 165 mb at E_{d} = 4.1 MeV. The t_{0} yield curve (θ_{lab} = 155°) decreases monotonically for E_{d} = 10.0 to 12.0 MeV: see (1974AJ01).
Observed proton groups are displayed in Table 9.5 (in PDF or PS). The parameters for the particle and γdecay of observed states are displayed in Tables 9.6 (in PDF or PS) and 9.3 (in PDF or PS). Angular distributions have been reported in the range E(^{3}He) = 0.9 to 14 MeV [see (1974AJ01, 1979AJ01)] and at E(^{3}He) = 14 and 33 MeV (1983LE17, 1983RO22; p_{0}). See also ^{10}B, (1984ME11) and (1986SC35; applications).
Angular distributions of d_{0}, d_{1} and d_{2} have been reported at E_{α} = 30 MeV: see (1974AJ01). See also (1983BE51; theor.).
Angular distributions of the αgroups to ^{9}Be*(0, 2.43, 6.76) have been measured at E(^{7}Li) = 78 MeV (1986GLZV: prelim.). For the excitation of ^{4}He* see (1987GLZX; prelim.; E(^{6}Li) = 93 MeV). For the earlier work see (1974AJ01).
^{9}Li decays by β^{} emission with τ_{1/2} = 178.3 ± 0.4 msec to several ^{9}Be states: see reaction 1 in ^{9}Li and Table 9.7 (in PDF or PS). Measurements of βα coincidences involving ^{9}Be*(11.28) show contributions from the direct n + 2α breakup process as well as the sequential nemission to ^{8}Be*(3.0)[J^{π} = 2^{+}], followed by breakup into 2α. The branching ratio for the ^{9}Be*(2.43) → ^{8}Be_{g.s.} + n decay is (6.4 ± 1.2)%. ^{9}Be*(2.78) [J^{π} = 1/2^{}] decays mainly to ^{8}Be_{g.s.} + n, presumably by pwave neutron emission: see (1979AJ01, 1984AJ01) for references, and (1988MI03) for a discussion of the evidence.
The photoneutron cross section has been measured from threshold to 320 MeV: see Table 9.6 (in PDF or PS) in (1966LA04), (1979AJ01) and (1988DI02). A pronounced peak occurs ≈ 29 keV above threshold with σ_{max} = 1.33 ± 0.24 mb. The shape of the resonance has been measured very accurately for E_{γ} = 1675 to 2168 keV. The FWHM of the peak is estimated to be 100 keV (1982FU11). See also (1983BA52; theor.) and (1987KU05). The cross section then decreases slowly to 1.2 mb at 40 keV above threshold. From bremsstrahlung studies, peaks in the (γ, Tn) cross section are observed corresponding to E_{x} = 1.80 and 3.03 MeV. At higher energies, using monoenergetic photons, the (γ, Tn) cross section is found to be relatively smooth from E_{γ} = 17 to 37 MeV with weak structures which correspond to E_{x} = 17.1, 18.8, 19.9, 21.4, 22.4, 23.8 [± 0.2] MeV and 27 ± 0.5 MeV (broad). In the range E_{γ} = 18 to 26 MeV the integrated (γ, n_{0}) cross section is < 0.1 MeV · mb, that for (γ, n_{1}) = 2.4 ± 0.4 MeV · mb and the combined integrated cross section for (γ, n) to ^{8}Be*(16.6) and (γ,α_{0}) to ^{5}He_{g.s.} is 13.1 ± 2 MeV · mb. The total absorption cross section has been measured for E_{γ} = 10 to 210 MeV: it rises to ≈ 5 mb at ≈ 21 MeV, decreases to about 0 at 160 MeV and then increases to ≈ 1.5 mb at 210 MeV. An integrated cross section of 156 ± 15 MeV · mb is reported for E_{γ} = 10 to 29 MeV as is resonant structure at E_{γ} = 11.8, (13.5), 14.8, (17.3), (19.5), 21.0, (23.0), and (25.0) MeV. Fine structure is also reported at E_{γ} = 20.47 ± 0.04 and 20.73 ± 0.04 MeV. See (1979AJ01) for references. At E_{γ} = 1.58 MeV, the cross section for reaction (c) is 0.40 ± 0.18 μb (1983FU13). For the electroproduction and photoproduction of helium nuclei for E_{e} = 100 to 225 MeV see (1986LI22). For hadron production at high energies see (1983AR24). See also (1987GO1Q), (1982DR08; applications), (1983FR1B, 1984GE1A, 1985AH06, 1985HA1H) and (1983BE45, 1983BO1B, 1983CA22, 1984KO33, 1985GO1A, 1985SH24, 1986JI01, 1987TE1E; theor.).
The yield shows structure in the energy region corresponding to the ^{9}Be levels at 17  19 MeV followed by the giant resonance at E_{γ} ≈ 23 MeV (σ = 2.64 ± 0.30 mb). Structure attributed to eleven states of ^{9}Be with 18.2 < E_{x} < 32.2 MeV has also been reported. Integrated cross sections have been obtained for each of these resonances, and over different energy intervals for protons leading to ^{8}Li*(0 + 0.98, 2.26 + 3.21, 9.0, 17.0). Angular and energy distributions of photoprotons in various energy intervals have been studied by many groups: see (1974AJ01) for references. For momentum spectra of protons using tagged photons with E_{γ} = 360 → 600 MeV, see (1984BA09). See also (1984AJ01) and (1984HO24). The integrated cross sections are reported to be 1.0 ± 0.5 MeV · mb (E_{γ} = 21 → 33 MeV) for reaction (c) to ^{7}Li*(0 + 0.4) and 0.6 ± 0.3 MeV → mb (E_{γ} = 25 → 33 MeV) for reaction (d) to ^{6}Li(0). The total integrated cross section for [(γ, p) + (γ, pn) + (γ, d) + (γ, t)] is 33 ± 3 MeV · mb. Resonances in the (γ, d) and (γ, t) cross sections corresponding to ^{9}Be*(26.0 ± 0.2) and ^{9}Be*(32.2 ± 0.3), respectively, have been reported: see (1974AJ01). For momentum spectra of deuterons and tritons at E_{γ} = 360 → 600 MeV see (1986BA07). Cross sections have been measured in the region of the Δ(1232) resonance by (1984HO09) [(γ, pn), (γ, 2p)], (1987KA13) [(γ, p), (γ, pn), (γ, 2p)] and (1986AR06) [(γ, π^{0})]. For a high energy study of hadron production see (1983AR24). See also (1986MC1G), (1985HO27, 1985MA1G) and (1983TR04, 1986HO11, 1987LU1B; theor.).
The second T = 3/2 state of ^{9}Be at E_{x} = 16.98 MeV has been studied in this reaction: see Table 9.4 (in PDF or PS) and reaction 4 (1987ZI01). See also (1986ZI01). With E_{bs} = 31 MeV eight resonances in (γ, γ') are reported for 17.4 < E_{x} < 29.4 MeV (1984AL22).
b = 1.5_{0.2}^{+0.3} fm [b = oscillator parameter] < r ^{2} >^{1/2}_{M} = 3.2 ± 0.3 fm; Ω = 6 ± 2 μ_{N} · fm^{2} [this value of the magnetic octupole moment implies a deformation of the average nuclear potential]. The elastic scattering of electrons has been studied for E_{e} up to 700 MeV. Magnetic elastic scattering gives indications of both M1 and M3 contributions. Inelastic scattering populates a number of levels: see Table 9.8 (in PDF or PS). At E_{e} = 45 and 49 MeV ^{9}Be*(1.68) has a strongly asymmetric line shape, as expected from its closeness to the ^{8}Be + n threshold. The form factor is dominated by a 0p_{3/2} → 1s_{1/2} particlehole transition. ^{9}Be*(2.43) is strongly excited (1987KU05). Form factors have also been measured for ^{9}Be*(0, 14.39, 16.67, 16.98, 17.49) by (1983LO11; E_{e} = 100.0 to 270.2 MeV). See also (1986MA48, 1987HY01, 1985HY1A). (1984WO09) suggest that the T = 1/2 states [^{9}Be*(16.67, 17.49)] have J^{π} = 5/2^{+} and 7/2^{+}, respectively, and that they have large parentage amplitudes with ^{8}Be*(16.6 + 16.9) [J^{π} = 2^{+}], rather than with ^{8}Be_{g.s.}. See (1974AJ01, 1979AJ01, 1984AJ01) for other work and earlier references. Peaks are observed for the quasifree reaction and for the Δresonance at 72 ± 3 and 315 ± 20 MeV at E_{e} = 537 MeV, and at 115 ± 5 and 375 ± 10 MeV at E_{e} = 730 MeV. The FWHM widths for the quasifree reaction peaks are 80 ± 5 and 115 ± 5 MeV at E_{e} = 537 and 730 MeV (1984OC01, 1987OC01). For the deep inelastic cross sections at very high energies see (1984AR02). A parityviolation study using polarized 300 MeV electrons is reported by (1987OT1C; prelim.). See also (1984LI07, 1985LI15, 1986AC1A, 1986BA85, 1986LI1G), (1984DO20, 1985BE1K, 1985KI1A, 1987DE43, 1987FR1B, 1987HO1D, 1987HO1F) and (1983AL04, 1984CH20, 1984LI1E, 1986AZ01, 1986BE1L; theor.).
The elastic scattering, and inelastic scattering to ^{9}Be*(2.43, 6.76) have been studied at E_{π±} = 162 and 291 MeV. Quadrupole contributions appear to be quite important for the elastic scattering at 162 MeV, but are much less so at the higher energy: see (1984AJ01) and the "General" section here.
The population of ^{9}Be*(0, 1.7, 2.4, 3.1, (6.8)) has been reported in this reaction: see (1974AJ01). For the neutron decay of these states see Table 9.6 (in PDF or PS). Angular distributions have been measured at E_{n} = 3.5 to 14.93 MeV [see (1974AJ01, 1979AJ01, 1984AJ01)], at E_{n} = 7 to 15 MeV (1983DA22; n_{0}), 11 to 17 MeV (1985TE01; n_{0}, n_{2}), 14.6 MeV (1985HA02, 1986HAYU; n_{0}) and 14.7 MeV (1984SH01; n_{0}, n_{2}) as well as at E_{n} = 9 to 17 MeV (1984BY03; n_{0}, n_{2}; see also for transition to ^{9}Be*(6.76)). See also ^{10}Be, (1986MU07), (1986RO1H) and (1985BE59, 1985DI1B, 1985GU1D, 1987HAZS; theor.).
Elastic and inelastic angular distributions have been studied at many energies in the range E_{p} = 2.3 to 1000 MeV [see (1974AJ01, 1979AJ01, 1984AJ01)], at E_{p} = 2.31 to 2.73 MeV (1983AL10; p_{0}), 11 to 17 MeV (1986MU07; p_{0}) and 1 GeV (1985AL16; p_{0}) as well as at E_{pol. p} = 200 MeV (1985GLZZ; p_{0}; prelim.) and 220 MeV (1985RO15; p_{0}, p_{2}). The elastic distributions show pronounced diffraction maxima. A quadrupoledeformed opticalmodel potential is necessary to obtain a good fit to the p_{0} and p_{2} angular distributions: see (1974AJ01). The spinflip probability at E_{pol. p} = 31 MeV is ≈ 0 for the p_{2} group, which is expected in view of the collective nature of the transition (1981CO08). The structure corresponding to ^{9}Be*(1.7) is asymmetric, as expected: see reaction 16 and Table 9.8 (in PDF or PS) for its parameters. [At E_{p} = 13 MeV the spectra are dominated by ^{9}Be*(2.43) (1987KU05)]. The weighted mean of the values of E_{x} for ^{9}Be*(2.4) listed in (1974AJ01) is 2432 ± 3 keV. ^{9}Be*(3.1) has E_{x} = 3.03 ± 0.03 MeV, Γ = 250 ± 50 keV, J^{π} = 3.2^{+}, 5/2^{+}. Higher states are observed at E_{x} = 4.8 ± 0.2, 6.76 ± 0.06 [J^{π} = 1/2^{+}, 5/2^{+}, 7/2^{+} (but see below), Γ = 1.2 ± 0.2 MeV], 7.94 ± 0.08 (Γ ≈ 1 MeV), 11.3 ± 0.2 MeV (Γ ≈ 1 MeV), 14.4 ± 0.3 (Γ ≈ 1 MeV), 16.7 ± 0.3, 17.4 ± 0.3, 19.0 ± 0.4, 21.1 ± 0.5 and 22.4 ± 0.7 MeV [the five highest states are all broad]. For ^{9}Be*(2.4, 6.8) B(E2↑) = 49 ± 6 and 24 ± 4 fm^{4} and Γ(E2↓) = 0.0025 and 0.10 eV, respectively. The strong population of ^{9}Be*(2.4, 6.8) is consistent with the assumption that they have J^{π} = 5/2^{} and 7/2^{}, respectively, and are members of the ground state K = 3/2^{} band. See (1966LA04, 1974AJ01) for references. For K^{+} production see (1986AB07). See also ^{10}B, (1982BE1E), (1986MU07, 1986RO1H) and (1984SH1K, 1985GU1D, 1986BE1L, 1986NA15, 1987CU01, 1987HA01; theor.).
The reactions (p, 2p)X and (p, pd)X have been studied at E_{p} = 300 MeV (1983GR21, 1984HE03). For reactions (a) and (c) see also ^{8}Li, ^{8}Be (1985BE30, 1985DO16; 1 GeV) and (1984AJ01). Reaction (c) at E_{p} = 10  24 MeV involves ^{9}Be*(3.0, 4.7): see (1984AJ01). See also (1984WA21). For reactions (b) and (d) at E_{p} = 58 MeV see ^{7}Li, ^{6}Li and (1985DE17, 1984DE1F). For reactions (e) and (f) see (1985PAZL; E_{pol. p} = 70 MeV). The (p, pα) process (reaction (f)) has been studied at E_{p} = 150.5 MeV (1985WA13; see for S_{α}). For inclusive proton spectra yields see (1985SE15). See also (1983AN18, 1987BO1N), (1986CH1J) and (1983KA1A, 1984KO1E, 1985BO1A, 1985GA1A, 1985VD03, 1986ER1A, 1986OS08, 1987HA01; theor.).
Angular distributions have been measured in the range 1.0 to 410 MeV [see (1974AJ01, 1979AJ01, 1984AJ01)] and at E_{d} = 2.0 to 2.8 MeV (1983DE50, 1984AN16). See also ^{11}B in (1990AJ01). Inelastic groups have been reported to ^{9}Be*(1.7, 4.7, 6.8) and to states with E_{x} = 2431.9 ± 7.0 keV and 3040 ± 15 keV (Γ = 294 ± 20 keV): see (1974AJ01).
Angular distributions of elastically scattered tritons have been measured at E_{t} = 2.10 MeV and at E_{pol. t} = 15 and 17 MeV: see (1974AJ01, 1984AJ01). Reaction (b) at 4.2 and 4.6 MeV proceeds via ^{9}Be*(2.4): see (1974AJ01).
Angular distributions have been studied for E(^{3}He) = 1.6 to 46.1 MeV and at 217 MeV [see (1974AJ01, 1979AJ01, 1984AJ01)]. At E(^{3}He) = 39.8 MeV, ^{9}Be*(1.7, 2.4, 3.1, 4.7, 6.8, 14.4) are populated. Reaction (b) has been studied in a kinematically complete experiment for E(^{3}He) = 3 to 12 MeV (1986LA26) and 11.9 to 24.0 MeV (1987WA25). For the earlier work see (1984AJ01). See also (1987TR01; theor.).
Angular distributions have been studied at many energies in the range E_{α} = 5.0 to 104 MeV [see (1974AJ01, 1984AJ01)] and E_{α} = 23.1 MeV (1984HU1D, 1985HU1B; α_{0}, α_{2}). At E_{α} = 35.5 MeV, states belonging to the K = 3/2^{} groundstate band are strongly excited [^{9}Be*(0, 2.43, 6.76, 11.28); it is suggested that the latter has J^{π} = (9/2^{}); see, however, reaction 12]. The first three states belonging to the K = 1/2^{+} band are also excited [^{9}Be*(1.68, 3.05, 4.70)] (1982PE03; coupled channels analysis). For reaction (b) see (1983ZH09; 18 MeV); S_{α} = 0.96 [see (1984AJ01)] and (1987WA25; E(^{3}He) = 12 to 24 MeV). See also ^{8}Be, (1987BU27, 1987KO1K) and (1984LI28, 1985SR01; theor.).
Elastic angular distributions have been measured at E(^{6}Li) = 4, 6 and 24 MeV and at E(^{7}Li) = 24 and 34 MeV [see (1979AJ01)] as well as at E(^{6}Li) = 32 MeV (1985CO09; also to ^{9}Be*(2.43)) and 50 MeV (1988TRZY; prelim.) and E(^{7}Li) = 78 MeV (1986GLZV, 1986GLZU; also to ^{9}Be*(2.43, 6.76). For the interaction cross section at E(Li) = 790 MeV/A see (1985TA18).
Elastic angular distributions have been obtained at E(^{9}Be) = 5 to 26 MeV [see (1979AJ01, 1984AJ01)] and at 35 to 50 MeV (1984OM02; also to ^{9}Be*(2.43)). See also (1985JA09). For yields and cross sections see (1984OM03, 1986CU02). For the interaction cross section at E(^{9}Be) = 790 MeV/A see (1985TA18).
Elastic angular distributions have been reported at E(^{10}B) = 20.1 and 30.0 MeV (1983SR01). For yields and cross section measurements see (1983SR01, 1984DA17, 1986CU02). See also (1983DU13) and (1984IN03, 1986RO12; theor.).
Elastic angular distributions have been measured for reaction (a) at E(^{12}C) = 12, 15, 18 and 21 MeV and E(^{9}Be) = 14 to 76.6 MeV [see (1979AJ01, 1984AJ01)] and 158.3 MeV (1984FU10) as well as at E(^{12}C) = 65 MeV (1985GO1H; prelim.; various ^{12}C states). For yield and fusion crosssection measurements see (1983JA09, 1985DE22) and (1984AJ01). Elastic angular distributions for reaction (b) are reported at E(^{9}Be) = 14 to 26 MeV: see (1984AJ01). For yield measurements see (1984DA17, 1986CU02). See also (1983DU13, 1984FR1A, 1984HA53, 1985BE1A, 1985CU1A) and (1982GU21, 1983KA17, 1983OH04, 1983SA20, 1984HA43, 1986BA69, 1986HA13, 1986KA22, 1986MI24; theor.).
Elastic angular distributions have been measured at E(^{14}N) = 25 and 27.3 MeV: see (1974AJ01). For a fusion study see (1984MA28).
Elastic angular distributions have been reported in the range E(^{16}O) = 15 to 30 MeV [see (1979AJ01)], at E(^{9}Be) = 14, 20 and 26 MeV [see (1984AJ01)], 43 MeV (1985WI18) and 157.7 MeV (1984FU10), as well as at E(^{18}O) = 12.1, 16 and 20 MeV [see (1974AJ01)]. See also (1983BI13, 1983DA10, 1985BE1A, 1985CU1A) and (1982GU21, 1983GR18, 1983SA20, 1984HA43, 1988PO1D; theor.).
Elastic angular distributions have been measured for many of these reactions: see (1979AJ01, 1984AJ01). Recently they have been studied on ^{26}Mg and ^{40}Ca at E(^{9}Be) = 43 and 45 MeV, respectively (1985WI18) and on ^{26}Mg, ^{27}Al and ^{40}Ca at E(^{9}Be) = 158.1  158.3 MeV (1984FU10). For pion production in reaction (a) see (1985FR13). The interaction cross section for 790 MeV/A ^{9}Be on ^{27}Al has been measured by (1985TA18). Breakup measurements involving ^{40}Ca are reported by (1984GR20). See also (1983BI13, 1984FR1A, 1984HA53) and (1984GU09, 1985AN16, 1985BL18; theor.).
Forward angular distributions have been obtained at E_{d} = 15.0 MeV for the tritons to ^{9}Be*(0, 1.7, 2.4, 3.1). The groundstate transition is well fitted by l = 1. The transition to ^{9}Be*(1.7) [≈ 165 ± 25 keV] is consistent with J^{π} = 1/2^{+}, that to ^{9}Be*(2.4) is quite well fitted with l = 3 [J^{π} = 5/2^{}], and that to ^{9}Be*(3.1) [Γ = 280 ± 25 keV] is consistent with l = 2. No other narrow states are seen up to E_{x} = 5.5 MeV: see (1974AJ01).
See (1974AJ01) and ^{11}B in (1980AJ01).
See (1974AJ01) and (1985BE30, 1985DO16).
Angular distributions of the ^{3}He groups corresponding to ^{9}Be*(0, 2.4) have been studied at E_{d} = 11.8, 28 and 52 MeV [the latter also to ^{9}Be*(6.7)], and at E_{d} = 15 MeV: S = 0.72 and 0.82 for ^{9}Be*(0, 2.4). At E_{d} = 52 MeV ^{9}Be*(11.3) appears to be strongly populated: see (1979AJ01).
At E_{t} = 12.9 MeV αgroups are observed to the ground state of ^{9}Be and to excited states at E_{x} = 1.75 ± 0.03, 2.43, 3.02 ± 0.04 (Γ = 320 ± 60 keV), 11.27 ± 0.04 (Γ = 530 ± 70 keV), (14.4) [Γ ≈ 800 keV], 14.39 and 16.67 MeV. The T = 3/2 state ^{9}Be*(14.39) is very weakly populated [≈ 5% of intensity of α_{2}]. The angular distribution of the α_{2} group shows sharp forward and backward peaking. The α_{0} group is not peaked in the backward direction: see (1979AJ01). See also (1984AJ01) and (1982CI1A; theor.).
At E_{p} = 45 MeV angular distributions are reported for the ^{3}He ions corresponding to ^{9}Be*(0, 2.4, 11.8, 13.8, 14.39 [T = 3/2], 15.96 ± 0.04 [T = 1/2]). In addition one or more states may be located at ^{9}Be*(15.13). It is suggested that ^{9}Be*(11.8, 13.8, 15.96) are the J^{π} = 3/2^{}, T = 1/2 analogs to ^{9}Be*(12.06, 14.01, 16.02). Angular distributions are also reported at E_{p} = 40 MeV. The intensity of the group to ^{9}Be*(3.1) is ≈ 1% of the groundstate group at that energy: see (1974AJ01). The excitation energy of the first T = 3/2 state is E_{x} = 14392.2 ± 1.8 keV (1974KA15), using Q_{m}.
Alpha groups are reported corresponding to ^{9}Be*(0, 1.7, 2.4, 3.1). The width of ^{9}Be*(1.7) [E_{x} = 1.70 ± 0.01 MeV] is Γ_{c.m.} = 220 ± 20 keV. The weighted mean of the values of E_{x} of ^{9}Be*(2.4), reported in (1974AJ01), is 2425 ± 3 keV. The 5/2^{+} state is at E_{x} = 3.035 ± 0.025 MeV: Γ_{c.m.} = 257 ± 25 keV. The ratio Γ_{γ}/Γ of ^{9}Be*(1.7) ≤ 2.4 × 10^{5}, that for ^{9}Be*(2.4) is reported to be (1.16 ± 0.14) × 10^{4}. Since Γ_{γ} is known from (e, e') [see Table 9.8 (in PDF or PS): 0.089 ± 0.010 eV], Γ = 0.77 ± 0.15 keV. See (1974AJ01, 1979AJ01) for references. Angular distributions for α_{0} and α_{2} are reported at E_{d} = 0.39 to 3.9 MeV and at 12 MeV [see (1974AJ01, 1979AJ01)]. Reaction (b), at E_{d} = 10.4 and 12.0 MeV, proceeds via ^{9}Be*(2.4) and to some extent via ^{9}Be*(3.1, 4.7) and possibly some higher excited states. The dominant decay of ^{9}Be*(2.4) is to ^{5}He(0) + α while ^{9}Be*(3.1, 4.7) decay to ^{8}Be(0) + n. It should be noted, however, that the peaks corresponding to ^{9}Be*(3.0) have a FWHM of ≈ 1 MeV, which may imply that ^{9}Be*(2.8) is involved.
See (1986BU22, 1987BU1A, 1987VO08).
Angular distributions of the α_{0} group have been measured at E_{n} = 13.9 to 18.8 MeV [see (1974AJ01)] and at 14.1 MeV (1984HA48). ^{9}Be*(1.7, 2.4, 3.1, 6.8) are also populated. Reaction (b) at E_{n} = 13 to 18 MeV involves ^{9}Be*(2.4). See (1984HA48) for differential cross sections at 14.1 MeV and for partial and total cross sections.
See (1985DE17; E_{p} = 58 MeV).
See ^{7}Be.
For reaction (a) see ^{10}B. For reaction (b) see (1988KR11) and (1985OS06; theor.). For reaction (c) see (1986GO1B; E(^{14}N) = 150 MeV).
Angular distributions have been obtained at E(^{3}He) = 70 MeV for the transitions to ^{9}Be*(0, 2.4) and ^{7}Be*(0, 0.43). Broad states at 2.9, 4.8 ± 0.2, 7.3 ± 0.2 and 11.9 ± 0.4 MeV are also populated: see (1979AJ01).
See ^{8}Be here and ^{9}Be in (1979AJ01).
See (1986GO1B; E(^{14}N) = 150 MeV).
See (1987KW01, 1987KW03; theor.).
See ^{20}Ne in (1987AJ02). See also (1985KA1J).
