Coulomb excitation of the lead isotopes with α and 16O beams

摘要: Abstract The lead isotopes were Coulomb excited with α-particles of 15 and 18 MeV 16 O ions 70 80 MeV. By measuring the absolute yields de-excitation γ-rays very accurately, B ( Eλ ) values for first 2 + states in 204 Pb 206 Pb, 3 − 208 four 207 obtained. E2 transition strengths to two are well described by coupling these a quadrupole core excitation Pb. (E3) ⊗p 1 doublet show only slight deviations from weak value, yet lifetimes states, which determined Doppler-shift attenuation method, different model predictions. M1 rate state ground as lifetime 0.17 ps agrees value obtained (E2) mixing ratio measurement.