Data obtained by the associated production of A hypernuclei through the (n + ,K + ) reaction are presented for a wide range of mass numbers. The special features which make this reaction useful are pointed out. The reaction is shown to be an excellent probe of A single-particle states, as demonstrated by the excitation of deeply bound states which are interpreted as the weak coupling of a A to neutronhole states of the core. The A binding energies and ground-state production cross sections for JvBe, 'AC, '&>, 2 2Si, ^Ca, 5 A V, and ^Y are presented.

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Until recently, the spectroscopy of A-hypernuclei has been studied by use of the well-known, strangeness-exchanging (K,n) reactions. These reactions are typically characterized by small momentum transfer, q < qp, where qp is the Fermi momentum. They populate preferentially states of low angular momentum and are effective in producing "substitutior.al states" in which the A has the same orbital as the neutron it replaces (AL=0).

Dedicated to Professor Theo Mayer-Kuckuk on the occasion of his 60th birthdayThe line shape and the excitation strength of the very weak first excited J~= 1/2 + state at Ex= 1.684 MeV in 9Be has been investigated with high-resolution inelastic electron scattering at Eo=45 and 49 MeV and scattering angles 0=105% 117 ~ 129 ~ and 165% and with high-resolution inelastic proton scattering at E0=13 MeV and 0=15 ~ and 18 ~ Due to lying just above the neutron threshold the level has a strongly asymmetric line shape which in both experiments can be described consistently with a Breit-Wigner expression modified on the low energy side by the threshold behaviour of the cross section. The resonance energy is ER = 1.684_+ 0.007 MeV and the width F = 217 __ 10 keV in the c.m. system. A single particle potential model calculation reproduces the line shape and the resonance parameters fairly well. In addition, the inelastic electron scattering form factor has been measured. In the range of momentum transfers q = 0.24-0.46 fm-1 it is dominated by a 0P3/2 --" 1 $1/2 particle-hole transition. The transition is mainly longitudinal and of isoscalar nature with a strength of B(E1)T =0.027 _+0.002 e 2 fm 2, but a small M2 contribution of B(M2)T = 8.8_+ 1.5 #~ fm z has also been detected.

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