A Morphological Indicator for Comparing Simulated Cosmological Scenarios with Observations

We propose a morphological multi-scale analysis of large scale structures obtained by computer simulations and by observations. Structures are obtained at diierent scales by applying a wavelet transform on the observed and simulated data. Application of a segmenta-tion algorithm allows a quantitative morphological description of the structures at each scale. The morphological parameter which we propose represents the deviation of a structure from sphericity. The dependence on scale of this simple parameter is shown to characterize, in simulations , the underlying cosmological model. We compare the HDM, CDM and mixed models with the CfA catalogue. This comparison favours a mixed model containing 65% of CDM, 30% of HDM, and 5% baryonic matter.