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Positive-parity collective band structures of low-lying levels in even-even actinide nuclei were analyzed based on an extension of the Davydov-Chaban soft rotator model, which accounts for the rotation and b-and g -vibrations of even-even nuclei with non-axial quadrupole deformation . The parameters to reproduce the 4-bands, i.e., the ground-state rotational band, the Kr_??_2 band, and the nb=1 and n-g=1 bands, were obtained, and their systematic trends were deduced. Based on this result the unassigned band having a sequence of 0+, 2+, 4+,.., which is observed in many actinide nuclei, was assigned likely to be the nb=1 band. The systematic trends of the parameters found in this work could be a guide to estimate the collective band structure of nuclei for which such data are poorly known. The correct assignment of collective levels was found to be important for the calculation of neutron inelastic scattering cross sections.

In the three papers ͓1-3͔, an error was found in the calculation of the flux of the outgoing particle at a final N-N collision point in the nucleus. The error has been corrected with the following consequences.The correction affects the refraction of the outgoing particle by the distorting potential in the exit channel. Typical examples of the correction to Refs. ͓1,3͔ for 90 Zr(p, pЈx) at 160 MeV and 80 MeV are shown in Figs. 1 and 2, by which Figs. 1 and 2 of Ref. ͓3͔ should be replaced. Also, Figs. 1͑c͒ and 2͑c͒ are the revised Figs. 1͑a͒ and 3͑a͒ of Ref. ͓1͔, respectively. The effectof the correction appears particularly in the one-step cross sections at angles less than 40°. The steep drop-off of the one-step cross section at 0°seen in the previous calculation is weakened at 160 MeV, but the cross section still decreases toward 0°. In addition, the one-step cross sections near the quasielastic scattering angle around 30°are reduced and the agreement with the experimental data is improved. As shown in Fig. 2, the one-step cross section does not drop off toward 0°at lower incident energies, which is considerably different from the previous results of Refs. ͓1,3͔. This implies that the refraction effect becomes important as the incident energy decreases. We can conclude that the correction leads to better agreement with the experimental data at small angles, particularly for incident energies less than 80 MeV. It should be emphasized that there is little change in the one-step cross sections at larger angles and the two-and three-step cross sections. Therefore, the other conclusions drawn in Refs. ͓1,3͔ remain unchanged.The changes in the results of the cross sections calculated in Ref.͓2͔ are just the same as those described above. Figure 4 of Ref. ͓2͔ should be replaced by Fig. 3. The agreement with the data is worse than the previous one, although the sign and the qualitative features of the angular distribution of the calculated D NN are not changed. Since the corrected one-step cross sections do not go down at 0°and are much larger than the corresponding two-step cross sections as already mentioned, the calculated D NN at 0°is no longer considered questionable as in Ref. ͓2͔. Figure 6 of Ref. ͓2͔ should be replaced by Fig. 4. One can see that the in-medium effect is clearly seen in the calculated D NN in 90 Zr͑p,nx͒ reaction at 160 MeV in agreement with the conclusion of Ref. ͓2͔. The changes in Fig. 7 of Ref. ͓2͔ are quite small, which shows that the in-medium modification of the tensor force is indeed very important as stated in Ref. ͓2͔. In addition, a factor of 2 /(2ប 2 ) 2 should be replaced by a factor of 4 /(2ប 2 ) 4 in the right-hand side of Eq. ͑2.31͒ in Ref. ͓2͔. This is a typographical error and the correct equation was used in the calculation.Corrected figures for other reactions shown in the three papers ͓1-3͔ can be obtained from the authors.

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