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A phenomenological analysis is made of the binding-energy data for light hypernuclei in terms of a two-body A-nucleon interaction, in which account is taken of the empirical information available on the structure of light nuclei. It is found that the observed binding energies can be interpreted in terms of a spindependent A-nucleon interaction; the agreement obtained is adequate for any force-range between 0.4X 10~1 3 cm and 0.7X 10~1 3 cm (for Yukawa shape) and any exchange character for this interaction. From observations on AH 4 decay it is argued that the AH 4 , AHe 4 doublet has zero spin, which requires that the singlet A-nucleon interaction be more attractive than the triplet. The well-depth parameter for the singlet A-nucleon interaction has values from 0.90 to 0.85 for ranges between 0.4X10* -13 cm and 0.7X10 -13 cm, the triplet interaction being also attractive but only one-half to one-third as strong. Spin values are assigned to the light hypernuclei, and the angular correlations which could provide a check on these values are discussed. The absorption of K~ mesons in helium is discussed; it appears that the selection rules for the production of A = 4 hypernuclei in this reaction may be confused by the existence of an excited state AH 4 *, AHe 4 *. A number of uncertainties in the phenomenological analysis of the heavier hypernuclei are pointed out; the present data do not disagree with the conclusions based on the analysis of the lighter and better-known hypernuclei with A ^ 5, but they add little weight to these conclusions. et al. arises mainly from the use of a larger Q value for the free A decay: Q A =37.22±0.22 Mev. This value is the average (weighted by the number of events) of two determinations: QA=36.75±0.2 Mev [given by W. Slater, University of Chicago dissertation, 1958 (unpublished)] for 9 of the events reported by Friedlander, Keefe, Menon, and Merlin [Phil. Mag. 45, 533 (1954)] analyzed on the basis of the range-energy relation used in the world survey; and (>A=37.45±0.17 Mev given for 18 events by Barkas, Giles, Heckman, Inman, Mason, and Smith [University of California Radiation Laboratory Report UCRL-3892, 1957 (unpublished)]. Additional shifts in B A for A Li 7 and ALi 8 are due to the incorporation of new events. Further changes in QA (by AQA) will give rise to a change AQA in each of the BA values. 3 R. H.work more realistic assumptions are made about the range of the A-nucleon interaction, and the analysis is extended to include recent data on the heavier hypernuclei. The qualitative conclusions of the present work remain the same as those reported earlier, 3 however, and disagree with the conclusions reached by Brown and Peshkin 4 on the basis of the same assumptions as those of our earlier report. The A particle is now known to be an isotopic-spin singlet (T=0) state. Charge symmetry for strong interactions then requires that the A-neutron and A-proton interactions be identical. That strong support for this situation can be derived from the approximate equality of the BK values ...

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