Radioactive ion beams of 17F were used to study several resonance states in 18Ne. Clear evidence for simultaneous two-proton emission from the 6.15 MeV state (Jpi = 1(-)) in 18Ne has been observed with the reaction 17F+1H. Because of limited angular coverage, the data did not differentiate between the two possible mechanisms of simultaneous decay, diproton (2He) emission or direct three-body decay. The two-proton partial width was found to be 21+/-3 eV assuming 2He emission and 57+/-6 eV assuming three-body decay. The total width of the 1(-) state was measured to be 50+/-5 keV. Several additional resonances that decay by single proton emission were also studied.

Evaporation residue and fission cross sections of radioactive 132 Sn on 64 Ni were measured near the Coulomb barrier. A large subbarrier fusion enhancement was observed. Coupled-channel calculations, including inelastic excitation of the projectile and target, and neutron transfer are in good agreement with the measured fusion excitation function. When the change in nuclear size and shift in barrier height are accounted for, there is no extra fusion enhancement in 132 Sn + 64 Ni with respect to stable Sn + 64 Ni. A systematic comparison of evaporation residue cross sections for the fusion of even 112−124 Sn and 132 Sn with 64 Ni is presented. DOI: 10.1103/PhysRevC.75.054607 PACS number(s): 25.60.−t, 25.60.Pj 0556-2813/2007/75(5)/054607(9) 054607-1

Morsch et al. Reply:The author of the preceding Comment 1 questions the extraction of narrow giant-dipoleresonance (GDR) widths, a main point of our previous Letter. 2 His conclusion was derived from a different analysis using full statistical-model calculations, suggesting that the data were better described by large GDR widths.Meanwhile, we have performed full statistical-model calculations for all excitation energies and obtain results very similar to those in the Comment (by using the same parameters). However, a comparison with the experimental data (not done in the Comment) leads to the following conclusions:(1) The experimental data cannot be described adequately with either large or small GDR widths (see Fig. 1).(2) Divided spectra as shown in Ref. 2, Fig. 2, reveal a splitting of the GDR structure which can be explained only by narrow resonances. This must be true for any analysis, including those using statistical-model calculations.To prove this, the experimental data are divided by statistical-model calculations (see Fig. 2). Using the calculations with small GDR widths yields the spectrum in Fig. 2(a). This shows why the standard calculation fails to describe the data [point (l)]: A low-energy peak is observed which is well described by a Lorentzian at Eo = 7.5 MeV with T=4.2 MeV. In similar plots this peak is observed at all excitation energies and was also conjectured in other measurements. 3 Using statistical-model calculations including only this new peak yields Fig. 2(b) which shows a giant-resonance structure with splitting similar to Fig. 2 in Ref. 2. The description of this spectrum requires small resonance widths. In the original analysis presented in Ref. 1 the GDR widths were extracted by a fit with an empirical function, Tb = 300 MeV 162 MeV i ri L j iJLii 29 FIG. 1. /-ray spectrum, bremsstrahlung subtracted, for excitation energy E x -162 MeV, from Ref. 2. The solid and dashed lines indicate statistical-model calculations using small and large giant-resonance widths, respectively. The parameters were those discussed in the preceding Comment except for the solid line for which the energy-weighted sum-rule strength is reduced to 53%. J , L (a) EY = 162MeV **J*uiaiu nihil. Ill (b) FIG. 2. (a) y-ray spectrum divided by a model calculation, equivalent to the solid line in Fig. 1. The solid line is a Lorentzian fit to the structure at 7 MeV. (b) Same data divided by a calculation including only the new low-energy component; this shows the GDR structure. The solid and dashed lines represent calculations with narrow and broad GDR widths, respectively.inspired by the statistical model. The broad low-energy component found here is reflected in the old analysis in the value of the low-energy slope parameter T s , which is systematically larger than the value obtained for the standard statistical-model results (see Fig. 1).In summary, the y-ray spectra in Ref. 2 are not described by standard statistical-model calculations (discussed in the Comment), revealing a new low-energy dipole structure [ Fig...

The B(E2;0(+)-->2+) values for the first 2+ excited states of neutron-rich 132,134,136Te have been measured using Coulomb excitation of radioactive ion beams. The B(E2) values obtained for 132,134Te are in excellent agreement with expectations based on the systematics of heavy stable Te isotopes, while that for 136Te is unexpectedly small. These results are discussed in terms of proton-neutron configuration mixing and shell-model calculations using realistic effective interactions.

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