96-16U

Investigation of the critical behaviour of $n$-component 3D magnetic model in the vicinity of the phase transition at the temperatures $T>T_c$ is performed. Calculations were performed in the spirit of the renormalization group approach with using collective variables (CV) method. The phase transition temperature and the critical exsponents values are calculated. Calculation of the free energy is performed and the explicit analytical expressions for thermodynamic functions of the system as the functions of the temperature, external field and order parameter components number are obtained. The dependence of the obtained values on the microscopic parameters of the system is investigated. Calculations were performed in the frames of the $\rho_4$-model.