Salpeter equation in position space: Numerical solution for arbitrary confining potentials

1984; American Physical Society; Volume: 30; Issue: 3 Linguagem: Inglês

10.1103/physrevd.30.660

ISSN

1538-4500

Autores

L. J. Nickisch, Loyal Durand, Bernice Durand,

Tópico(s)

Black Holes and Theoretical Physics

Resumo

We present and test two new methods for the numerical solution of the relativistic wave equation $[{(\ensuremath{-}{\ensuremath{\nabla}}^{2}+{{m}_{1}}^{2})}^{\frac{1}{2}}+{(\ensuremath{-}{\ensuremath{\nabla}}^{2}+{{m}_{2}}^{2})}^{\frac{1}{2}}+V(r)\ensuremath{-}M]\ensuremath{\psi}(\stackrel{\ensuremath{\rightarrow}}{\mathrm{r}})=0$, which appears in the theory of relativistic quark-antiquark bound states. Our methods work directly in position space, and hence have the desirable features that we can vary the potential $V(r)$ locality in fitting the $q\overline{q}$ mass spectrum, and can easily build in the expected behavior of $V$ for $r\ensuremath{\rightarrow}0$,$\ensuremath{\infty}$. Our first method converts the nonlocal square-root operators to mildly singular integral operators involving hyperbolic Bessel functions. The resulting integral equation can be solved numerically by matrix techniques. Our second method approximates the square-root operators directly by finite matrices. Both methods converge rapidly with increasing matrix size (the square-root matrix method more rapidly) and can be used in fast-fitting routines. We present some tests for oscillator and Coulomb interactions, and for the realistic Coulomb-plus-linear potential used in $q\overline{q}$ phenomenology.

Referência(s)