# A New Signal Model for Axion Cavity Searches from N-Body Simulations

## TL;DR

This paper introduces a new signal model for axion cavity searches based on advanced cosmological simulations, improving upon the traditional isothermal sphere model by accounting for realistic galaxy structures and baryonic effects.

## Contribution

It develops a novel signal model for axion detection using high-resolution cosmological simulations, capturing complex galaxy structures and baryonic physics.

## Key findings

- Signal shapes differ significantly from the isothermal sphere model.
- Proposed model improves accuracy of axion detection sensitivity.
- Projected bounds on axion dark matter from existing data.

## Abstract

Signal estimates for direct axion dark matter searches have used the isothermal sphere halo model for the last several decades. While insightful, the isothermal model does not capture effects from a halo's infall history nor the influence of baryonic matter, which has been shown to significantly influence a halo's inner structure. The high resolution of cavity axion detectors can make use of modern cosmological structure-formation simulations, which begin from realistic initial conditions, incorporate a wide range of baryonic physics, and are capable of resolving detailed structure. This letter uses a state-of-the-art cosmological N-body+Smoothed-Particle Hydrodynamics simulation to develop an improved signal model for axion cavity searches. Signal shapes from a class of galaxies encompassing the Milky Way are found to depart significantly from the isothermal sphere. A new signal model for axion detectors is proposed and projected sensitivity bounds on the Axion Dark Matter eXperiment data are presented.