A Way of Axion Detection with Mass $10^{-4} \text{-}10^{-3}$eV Using Cylindrical Sample with Low Electric Conductivity

Abstract

A dark matter axion with mass $m_a$ induces an oscillating electric field in a cylindrical sample placed under a magnetic field $B_0$ parallel to the cylinder axis. When the cylinder is made of a highly electrically conductive material, the induced oscillating current flows only at the surface. In contrast, if the cylinder is composed of a material with small conductivity, e.g. $σ= 10^{-3}\text{eV}$, the electric current flows inside the bulk of the cylinder. Within the QCD axion model, the power $P$ is estimated as $P\simeq 5.7\times 10^{-27}\mbox{W}g_γ^2 \Big(\frac{L}{100\mbox{cm}}\Big)\Big(\frac{R}{6\mbox{cm}}\Big)^2 \Big(\frac{B_0}{15\mbox{T}}\Big)^2 \Big(\frac{m_a}{10^{-4}\mbox{eV}}\Big)\Big(\frac{10}ε\Big)\Big(\frac{ρ_a}{0.3\rm GeVcm^{-3}}\Big)$ with radius $R$, length $L$, permittivity $ε= 10$ of the cylinder and axion energy density $ρ_a$, where $g_γ$ is model dependent parameter; $g_γ(\text{KSVZ}) = -0.96$ and $g_γ(\text{DFSZ}) = 0.37$. The detection of dark matter axions in our method may be feasible in the mass range $m_a =10^{-4}\text{-}10^{-3}\text{eV}$.

Figures (1)

• Figure 1: cylinder sample with length $L$ and radius $R$ under external magnetic field $\vec{B}_0$