The symmetry breakdown pattern is studied in models containing one fermionflavor multiplet and a multicomponent scalar field, supplemented with a chiralYukawa-interaction, and in presence of an explicit symmetry breaking sourcequadratic in the scalar field. In a detailed investigation of the model with$U_L(1) \times U_R(1)$ chiral symmetry it is shown that by diminishing thestrength of quadratic explicit symmetry breaking one can still keep stable themass ratio of the fermionic and the pseudo-Goldstone excitation. At the sametime the mass ratio of the two bosonic excitations appears to approach alimiting value depending only on the infrared value of the first ratio, but noton the microscopic (ultraviolet) coupling values. The observations receive ageneral interpretation by the existence of an ultraviolet fixed point locatedin the symmetric phase. Understanding the general conditions for its existenceallows the construction of a similar theory with $U_L(2) \times U_R(2)$ chiralsymmetry. All results of the present investigation were obtained withnonperturbative functional renormalisation group technique making use of thefirst two approximations to the gradient expansion of the effective action.
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