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In this Letter, we reported a study of the Snð; tÞ reaction at 40 MeV, on the seven stable, even Sn isotopes, to study the pattern of 11=2 À and 7=2 þ single-particle states as the neutron excess changes. The interpretation of the data relied only on the relative cross sections for these 14 transitions. The absolute cross sections given in Table I, columns 2 and 3, have now been found to be in error. This error has no impact on the rest of the paper, which utilized only the relative values of the cross sections. A numerical error in a measured quantity should, however, be corrected.In the experiment, the cross sections were normalized to the yield for elastic scattering in a monitor detector placed at 9.1 . The collimator in front of the detector had a diameter of 1 mm. In the analysis, it was mistakenly assumed to have had a 1-mm radius.The problem came to light in a recent experiment where the same reaction was studied at 37.5 MeV and significantly different cross sections were found [1], lower by a factor of $3:7 if corrected for a small energy dependence, than those in the Letter. This factor is reasonably constant, showing a rms variation of 8.6% among the 14 transitions. This fluctuation is consistent with the estimated uncertainties from other sources.In all subsequent experiments by our group, utilizing the spectrograph at the Yale tandem facility (e.g., Ref.[2]), a different technique for determining the absolute cross sections was used, a method that did not depend on a monitor at small angles. Instead, the target thicknesses were calibrated by measuring scattering at low bombarding energies and at larger scattering angles. This calibration was done directly with the spectrograph, using the same aperture as in the rest of the measurements. Therefore, the mistake reported here has no effect on the results reported from our subsequent measurements at Yale. *schiffer@anl.gov [1] A. J. Mitchell, Ph.D. thesis, University of Manchester, 2012; the data will be submitted to XUNDL, http://www.nndc.bnl.gov/ xundl/. [2] J. P. Schiffer et al., Phys. Rev. Lett. 108, 022501 (2012).

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A measurement of the β-delayed α decay of 16 N using a set of twin ionization chambers is described. Sources were made by implantation, using a 16 N beam produced via the In-Flight Technique. The energies and emission angles of the 12 C and α particles were measured in coincidence and very clean α spectra, down to energies of 450 keV, were obtained. The structure of the spectra from this experiment is in good agreement with results from previous measurements. An analysis of our data with the same input parameters as used in earlier studies gives S E1 (300) = 86 ± 22 keVb for the E1 component of the S-factor. This value is in excellent agreement with results obtained from various direct and indirect measurements. In addition, the influence of new measurements including the phase shift data from Tischhauser et al. on the value of S E1 (300) is discussed.

The 62Ni(n,gamma)63Ni(t(1/2)=100+/-2 yr) reaction plays an important role in the control of the flow path of the slow neutron-capture (s) nucleosynthesis process. We have measured for the first time the total cross section of this reaction for a quasi-Maxwellian (kT=25 keV) neutron flux. The measurement was performed by fast-neutron activation, combined with accelerator mass spectrometry to detect directly the 63Ni product nuclei. The experimental value of 28.4+/-2.8 mb, fairly consistent with a recent calculation, affects the calculated net yield of 62Ni itself and the whole distribution of nuclei with 62