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589Notes to Table I. Absolute values of the reduced widths were estimated from the ground-state data of Re56. b The ridiculously low ro needed to fit the angular distribution is probably connected with "internal" or "volume" effects.'Levels at this excitation lie close to the nucleon separation energy (Q+2.23 =0), where the behavior of the Butler formula is sometimes erratic. Both l =1 and l =2 give a reasonably good fit, with l =2 slightly favored, particularly in the case of Ca58. Both relevant experiments were originally fitted with l =1. See Sec. IV for further discussion of ths point, which was brought to our attention by E. W. Hamburger (private communication). 'Although the curve shows a peak in the characteristic l =1 location, the direct l =1 transition is forbidden by conservation of angular momentum. The background is very high, however, and there is a marked backward maximum. The mechanism of this transition has been analyzed in terms of the so-called "exchange" and "spin-fiip" stripping. (See Au60 for discussion and references. )These levels are not resolved in Ev54. An upper limit of 15% is set in Co57 to the contribution from the 6.81-Mev level, enabling us to give a rough reduced width for the 6.76-Mev level. & Reduced widths relative to ground-state reduced width, as usual. h Neutrons to eight other levels below 9 Mev were observed, two strong unresolved l =1 groups being found. No quantitative reduced-width data could be obtained.' No measurements for 0 c.m. &35, so that no reliable reduced width ' could be extracted. & The neutron group corresponding to this transition was too weak to be analyzed.Only the ground-state cross section was remeasured in Ho53c. Since no measurements were reported for 9 c.m. &20', the Butler curves, particularly for this l =1 transition, had to be fitted at undesirably high angles, and the reduced widths are, accordingly, subject to large errors. i McGruer et aL. (McS6) quote an error of +50% in the absolute cross sections. Recent measurement by E. W. Hamburger and S. Mayo (quoted in Ha59) indicates that the cross sections of Mc56 are too high by 30%. This correction has been made in extracting the relevant reduced widths. It also affects the C'3(d, p)Ci4 results of Mc56. m These levels life far above the neutron separation energy (Q+~z =0). The Butler curves for different l(=0, 1, 2) are no longer very different. The l values, however, are obtained unambiguously in C»(e, e)C» experiments (Wi58). The 7.47and 7,53-Mev levels do not appear in the neutron experiments. These matters were brought to out attention by E. W. Hamburger (private communication).Unresolved. Probably a superposition of l =1 and l =2.

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