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Register a new userScattering and bound states of Dirac Equation in presence of cosmic string for Hulthen potential
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In this work we study the Dirac equation with vector and scalar potentials in the spacetime generated by a cosmic string. Using an approximation for the centrifugal term, a solution for the radial differential equation is obtained. We consider the scattering states under the Hulth{e}n potential and obtain the phase shifts. From the poles of the scattering $S$-matrix the states energies are determined as well.
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The relativistic quantum motion of scalar bosons under the influence of a full vector (minimal $A^{mu}$ and nonminimal $X^{mu}$) and scalar ($V_{s}$) interactions embedded in the background of a cosmic string is explored in the context of the Klein-Gordon equation. Considering Coulomb interactions, the effects of this topological defect in equation of motion, phase shift and S-matrix are analyzed and discussed. Bound-state solutions are obtained from poles of the S-matrix and it is shown that bound-state solutions are possible only for a restrict range of coupling constants.
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