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The energy of normal liquid $^3He$ is obtained using the lowest order constrained variational(LOCV) method. In order to test the vonvergence of the cluster expansion series, the three-body cluster energy is calculated, with the LOCV correlation functions, and by imposing the normaliztion constraint on the two-body distribution function which includes three-body cluster correlations(LOCVE). It is shown that the normalization constraint plays an important role in leeping the higher cluster terms small. The resulting LOCVE calculation for the ground state energy of liquid $^3He$ is compared with the available experimental data and the prediction from different theoretical techniques.
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