Magnetars as Laboratories for Strong Field QED

Chul Min Kim; Sang Pyo Kim

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arXiv · 2112.02460

Magnetars as Laboratories for Strong Field QED

Chul Min Kim·Sang Pyo Kim

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Abstract

A strong electromagnetic field polarizes the vacuum and in the presence of an electric field creates pairs of a charged particle and its anti-particle. Magnetars, highly magnetized neutron stars with magnetic field comparable to or greater than the Schwinger field, give a significant amount of the vacuum polarization and vacuum birefringence and the induced electric field can create the electron-positron pairs, which are strong field quantum electrodynamics (QED) processes. In this paper, we use a closed formula for the one-loop effective action in the presence of a supercritical magnetic field and a subcritical electric field, find the vacuum birefringence analytically and numerically, and then discuss possible measurements in magnetars.

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Chul Min Kim, Sang Pyo Kim. 2021-12-05. Magnetars as Laboratories for Strong Field QED. https://arxiv.org/abs/2112.02460

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