A consistent method for calculating the interquark potential generated
by the relativistic string with massive ends is proposed. In this app
roach, the interquark potential in the model of the Nambu-Goto string
with pointlike masses at its ends is calculated. At first the calculat
ion is done in the one-loop approximation. For obtaining a finite resu
lt under summation over eigenfrequencies of the Nambu-Goto string with
massive ends, an appropriate renormalization procedure is suggested.
It is shown that in this case the Luscher term in the string potential
acquires a dependence on the quark mass which results in the reductio
n of the absolute value of this term. Then the interquark potential in
the string model with new boundary conditions is calculated by making
use of the variational estimation of the corresponding functional int
egral.-In this case the quark mass correction results in decreasing th
e critical distance (deconfinement radius) in the string potential. In
the framework of the developed approach, the one-loop interquark pote
ntial in the model of the relativistic string with rigidity is also ca
lculated.