The reorientation effect in Coulomb excitation has been used to measure the static quadrupole moment Q2+ and B(E2;0+->2+) for the 1�779 MeV first excited state of 28Si. The results obtained are Q2+ = +15�5�3�4 efm2 and B(E2;0+->2+) = 326�20 e2fm4 ? The value obtained for Q2+ confirms the results of other recent determinations using the reorientation effect, and the B(E2; 0+ -> 2 +) value is in excellent agreement with the mean value deduced from previous lifetime determinations. Shell model and Hartree-Fock calculations of Q2+ both give a good account of the experimental result.
The corrections for mutual excitation given in Table 2 are wrong. They should read +0�2 efm2 for ilQ (instead of -0�2) and + 1 e2 fm4 for ilB(E2; 0+ ->2+) (instead of - 21). Consequently, the results of the experiment are Q2 + = + 15�9 � 3�4 efm2 and B(E2;0+->2+) = 348�20e2 fm4 ? The conclusions of the paper are not significantly affected.
The reorientation effect in Coulomb excitation with 62 MeV 35Cl projectiles was used to measure the static quadrupole moment of the first excited state in 24Mg. From a comparison of the inelastic scattering cross sections at CM scattering angles of 123.1° and 72.8°, a static quadrupole moment of Q = −0.243 ± 0.035 b was deduced. The E2 matrix element connecting the ground state and first excited state was also measured and corresponds to 20.3 ± 1.4 W.u. for the 2+ → 0+ transition. The results are compared with predictions of the rotational model.
Static Quadrupole Moment of the First Excited State of 28Si
