Magnetic coupling of planets and small bodies with a pulsar wind"

TL;DR

This paper explores how relativistic pulsar winds interact electromagnetically with orbiting planets or small bodies, extending Alfvén wing theory to relativistic regimes and revealing significant induced currents comparable to pulsar magnetospheric currents.

Contribution

It extends the theory of Alfvén wings to relativistic stellar winds, analyzing electromagnetic interactions with orbiting bodies around pulsars.

Findings

Relativistic winds can induce strong electric currents in orbiting bodies.

The induced currents can reach magnitudes comparable to the pulsar's Goldreich-Julian current.

Electromagnetic interactions may influence the dynamics of planets and small bodies around pulsars.

Abstract

We investigate the electromagnetic interaction of a relativistic stellar wind with a planet or a smaller body in orbit around the star. This may be relevant to objects orbiting a pulsar, such as PSR B1257+12 and PSR B1620-26 that are expected to hold a planetary system, or to pulsars with suspected asteroids or comets. We extend the theory of Alfv\'en wings to relativistic winds. When the wind is relativistic albeit slower than the total Alfv\'en speed, a system of electric currents carried by a stationary Alfv\'enic structure is driven by the planet or by its surroundings. For an Earth-like planet around a "standard" one second pulsar, the associated current can reach the same magnitude as the Goldreich-Julian current that powers the pulsar's magnetosphere.