Smoking gun signature from axion and the constraints with radio telescopes

TL;DR

This paper proposes an improved method for detecting axions via radio telescopes near magnetars, setting new constraints and demonstrating the potential for future detections within specific axion mass ranges.

Contribution

It refines axion-photon conversion calculations, develops a matched filtering method, and validates the approach with real data, enhancing detection prospects with radio telescopes.

Findings

New constraint on axion-photon coupling from TMRT data

Potential to detect axions with FAST or SKA within 10 hours

Validated detection method reduces spectrum confusion

Abstract

Axions are an elegant solution to the strong CP problem for particle physics and a promising dark matter candidate. They can convert into photons under a strong magnetic field, while magnetars with extreme magnetic fields are natural labs for axion detection. Radio telescopes can detect the radio emission from axion-photon conversion near magnetars. In this study, we have refined the calculation of axion-photon conversion and developed the matched filtering integration method to largely improve the signal-to-noise ratio. We validate our method using end-to-end simulation and real observational data from TMRT. A new constraint is set with only 687 seconds of observations with TMRT. Using 10 hours of observation with the high-frequency receiver in FAST or SKA, we can reach the theoretical coupling constant prediction for the axion mass range from 1$\mu$eV to 100$\mu$eV. We validate the possibility of axion detection with radio telescopes and avoid spectrum confusion.