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On the Threshold for the Pair Production and Localization of Spinless Particles

Tatiana R. Cardoso·Antonio S. de Castro
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Abstract

The one-dimensional Klein-Gordon equation is investigated with the most general Lorentz structure for the external potentials. The analysis of the scattering of particles in a step potential with an arbitrary mixing of vector and scalar couplings reveals that the scalar coupling contributes for increasing the threshold energy for the particle-antiparticle pair production. Furthermore, it is shown that the pair production is only feasible whether the vector coupling exceeds the scalar one. An apparent paradox concerning the localization of a particle in an arbitrarily small region of space, due to the presence of the scalar coupling, is solved by introducing the concept of effective Compton wavelength.

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Tatiana R. Cardoso, Antonio S. de Castro. 2007-02-14. On the Threshold for the Pair Production and Localization of Spinless Particles. https://arxiv.org/abs/quant-ph/0702143

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