DEPENDENCE ON THE MASS-NUMBER OF ENERGY QUANTITIES OF A LAMBDA IN HYPERNUCLEI WITH THE COSH AND THE GAUSSIAN POTENTIAL

The A binding energies obtained from the (pi+, K+) data are analyzed w ith the aid of suitable LAMBDA-nucleus potentials. Exact and approxima te analytic expressions, as functions of the mass number, for the bind ing energy and other energy quantities of a LAMBDA hyperon in hypernuc lei in ground and excited states are proposed and the region of their validity is discussed. The density dependence of the LAMBDA-nucleus po tential is taken into account in an approximate way and it turns out t hat its role is essential for a reliable description of the recent hyp ernuclear data. The formulas for the ground state LAMBDA energy are us ed to derive approximate expressions for the LAMBDA binding energy in double LAMBDA hypernuclei.