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arXiv · 2006.14159

Scalar scattering amplitude in Gaussian wave-packet formalism

Kenzo Ishikawa·Kenji Nishiwaki·Kin-ya Oda
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Abstract

We compute an $s$-channel $2\to2$ scalar scattering $\phi\phi\to\Phi\to\phi\phi$ in the Gaussian wave-packet formalism at the tree-level. We find that wave-packet effects, including shifts of the pole and width of the propagator of $\Phi$, persist even when we do not take into account the time-boundary effect for $2\to2$, proposed earlier. The result can be interpreted that a heavy scalar $1\to2$ decay $\Phi\to\phi\phi$, taking into account the production of $\Phi$, does not exhibit the in-state time-boundary effect unless we further take into account in-boundary effects for the $2\to2$ scattering. We also show various plane-wave limits.

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Kenzo Ishikawa, Kenji Nishiwaki, Kin-ya Oda. 2020-06-25. Scalar scattering amplitude in Gaussian wave-packet formalism. https://arxiv.org/abs/2006.14159

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