On the excitation of isoscalar dipole strength in the giant resonance region by inelastic electron and hadron scattering

The possible excitation of isoscalar dinole strength in the region of the giant resonances is investigated. The presence of 20% of the isoscalar dipole energy-weighted sum rule (EWSR) in the region of the giant quadrupole resonance (GQR) would have an appreciable cross section as compared to the total cross section attributed to GQR excitation, and would readily account for the forward-backward asymmetries observed in α0-decay of the GQR in light nuclei

Excitation of the 21+ and 22+ states in the 88Sr(p, p′) reaction at 25 and 31 MeV:A look behind the nuclear surface

Data for the excitation of the 21+ and 22+ states in the 88Sr(p, p′) reaction at 25 and 31 MeV indicate substantial contributions from the interior of the nucleus, Microscopic DWBA calculations reproduce this and yield a fair description of the data. A detailed description, especially of the 22+ state, is sensitive to the effective nucleon-nucleon interaction used and the non-locality of the optical potential, which are insufficiently known at present

The isoscalar quadrupole strength distribution above 10 MeV in 40Ca

From angular correlation measurements of c~ o decay to the 36At ground state, the isoscalar E2 strength distribution between 10 and 16 MeV in 4°Ca has been found to be concentrated in the interval E x = 12.5-15.5 MeV and to exhaust +10 about 12% of the EWSR in the c~ o channel and about (45-15 )% if extrapolated to all channels

Fission decay of the isoscalar giant quadrupole resonance in 24Mg

The 24Mg(ot, a') 12C+12C reaction was studied by measuring 12C fragments in coincidence with inelastically scattered a-particles at E,=120 MeV. Both 12C fragments were identified using the AE-E technique. The measured angular correlations indicate that the 12Cg~ + 12Cg S decay channel is dominated by decay of L = 2 strength, which yields an integrated fraction of 0.14% of the E2 EWSR strength in comparison with 22.2% of the E2 EWSR strength observed in singles inelastic a-scattering experiments in the same excitation energy region

Experimental determination of monopole strength in 40Ca between 10 and 20 MeV excitation energy

The distribution of isoscalar monopole strength in 40Ca was determined from singles 40Ca(α, α′) and from coincident 40Ca(α,α′α0) data at Eα =120 MeV and scattering angles from 0° to 3°. Between 10.5 and 15.7 MeV excitation energy (23±5)% of the EO EWSR was located from the singles and from the coincidence measurements independently, while (30 ±6)% of the EO EWSR was found in the interval 10.5–20 MeV from the singles data only

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