A simple high-accuracy method for solving bound-state equations with the Cornell potential in momentum space

We present a simple, high-accuracy method for solving bound-state integral equations in momentum space with singular kernels. For the case of the linear-confining potential, the associated Cauchy-principal-value singularity is removed by subtraction. Derivatives of the wave function that appear as a result of the subtraction technique are approximated by means of interpolating functions. The resulting non-singular integral equation is solved using the Nystr\"om method. The results show excellent agreement with exactly known energy eigenvalues. By further increasing the number of integration points and the order of the Lagrange interpolation, results with extremely high accuracy can be achieved.