Dissecting axion and dark photon with a network of vector sensors

TL;DR

This paper proposes a formalism for a network of vector sensors to detect and analyze signals from light axions or dark photons, enabling detailed characterization of their properties and origins.

Contribution

It introduces a novel formalism for vector sensor networks to identify and distinguish axion and dark photon signals, including their polarization and source characteristics.

Findings

Network of vector sensors can detect axion and dark photon signals.

Method can differentiate between axion-fermion and dark photon couplings.

Potential to localize sources and determine polarization modes.

Abstract

We develop formalisms for a network of vector sensors, sensitive to certain spatial components of the signals, to identify the properties of a light axion or a dark photon background. These bosonic fields contribute to vector-like signals in the detectors, including effective magnetic fields triggering the spin precession, effective electric currents in a shielded room, and forces on the matter. The interplay between a pair of vector sensors and a baseline that separates them can potentially uncover rich information of the bosons, including angular distribution, polarization modes, source localization, and macroscopic circular polarization. Using such a network, one can identify the microscopic nature of a potential signal, such as distinguishing between the axion-fermion coupling and the dipole couplings with the dark photon.