The statistical multifragmentation model (A. H. Raduta et al.) will be improved such as to take into account the fragment deformation degrees of freedom and to acheive realistic features specific to dynamical simulations. The modification is supposed to r estore the van der Waals shape of the nuclear phase diagram calculated via statistical models. The new version of the model and results of dynamical simlations at frezee-out will be comparatively applied in all evaluations thus contributing to the solidi ty of the obtained results. The phase diagrams of various nuclear systems will be evaluated and their evolution with size, presence or absence of the Coulomb field and isospin will be investigated. The correlation between the position of the system in the phase diagram and the average isospin of the produced fragments and isoscaling will be investigated. Scaling analyses resulting in identifying the system's critical exponents and, consequently its universality class will be performed. The sharp microcano nical heat capacity formulas recently proposed (A. H. Raduta et al.) will be paralelly applied on multifragmentation data and predictions of statistical and dynamical (BUU or QMD) simulations at various moments in time, thus drawing a solid conclusion conc erning the existence of a liquid-gas phase transition in nuclear matter. Finally, an investigation will be made concerning the relevance of the concept of freeze-out. Can one really identify a distinct, statistically equilibrated stage in the process of collision between two heavy ions? Estimators for equilibrium will be designed and their value will be measured in time for the case of dynamical simulations. Whatever the result, this kind of analysis will help in gaining realism concerning the statistical nature of nuclear multifragmentation and parameters crucial in establishing the system thermodynamics like the freeze-out volume will be identified.
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