StrongE1transitions inBe9,

Structure of unstable light nuclei

“…The MK interaction was "hand crafted" to give a good account of the relative separation of the 1s 1/2 and 0d 5/2 centroids as a function of mass number, through 13 C and down to 11 Be. More attention was given to A = 11 by Teeters and Kurath [68] and by Millener and collaborators in studies of the the β decay of 11 Be [69] and the fast E1 transition in 11 Be [70]. Warburton and Brown [24] have subsequently shown that it is possible to obtain a successful fit with an rms deviation of ∼ 330 keV to a large number of cross-shell energies from A = 10 − 22, including some for 2 ω configurations.…”

“…A recent measurement of µ = −1.6816 (8)µ N for the magnetic moment of 11 Be [75], which is sensitive to the 2 + ⊗ d 5/2 admixture [76], tends to confirm the MK parentage which gives µ = −1.71µ N when bare-nucleon g-factors are used. Note that Suzuki et al [76] used a a quenched spin g-factor based on the tabulated value of µ = −1.315 (70)µ N for 15 C. However, this value appears only in a conference proceedings and I strongly suspect that it is not correct; based on the parentage for 15 C ground states in Table 2, µ( 15 C) should be closer to the Schmidt value than µ( 11 Be).…”

Investigation of E1 Strength in Coulomb Excitation of Light Nuclei

“…(1) n where the sum is over all intermediate states n that are connected by the El operator to both i and f. The reduced matrix elements are as defined by de-Shalit and Talmi (1963). The relation between Tif and the quantity 5(El) * Contrary to the implication by Gomez-Camacho and Nagarajan (1985), Barker (l982a) included excitation of nucleons from both the 1 sand 1 p shells.…”

“…These calculations were put on a more rigorous basis by Barker and Ferdous (1980), for El transitions in both l3e and 13N. Millener et al (1983) considered other cases of strong El transitions between low-lying levels of light nuclei, where use of Woods-Saxon wavefunctions increased B(E1) values calculated with harmonic oscillator wavefunctions by factors of up to 50. The increase is generally associated with an increase (by a factor of order 2-3) in the El single-particle matrix element (SPME) involving alp -+ 2s transition of a nucleon that is loosely bound, whose wavefunction therefore extends out to large distances.…”

“…In their calculations, Barker and Ferdous (1980) and Millener et al (1983) expressed each El matrix element in terms of contributions from single-particle transitions corresponding to different core states, so that the single-particle wavefunctions could be calculated with the appropriate binding energy. It is impracticable to do this for each of the El matrix elements that we need (the numbers range from 51 in 6Li to 930 in 11 B).…”