Search for light scalar Dark Matter candidate with AURIGA detector

TL;DR

This paper reports a search for light scalar dark matter particles, called moduli, using the AURIGA detector, setting new upper limits on their coupling to matter around specific low masses.

Contribution

First experimental search for scalar moduli dark matter using a cryogenic resonant-mass detector, providing constraints on their coupling at low masses.

Findings

Set upper limits on moduli coupling at $d_{e}\lesssim10^{-5}$

Focused on moduli mass around $3.6\times10^{-12}$ eV

Achieved strain sensitivity of $h_{s}\sim2\times10^{-21}$ Hz$^{-1/2}$

Abstract

A search for a new scalar field, called moduli, has been performed using the cryogenic resonant-mass AURIGA detector. Predicted by string theory, moduli may provide a significant contribution to the dark matter (DM) component of our universe. If this is the case, the interaction of ordinary matter with the local DM moduli, forming the Galaxy halo, will cause an oscillation of solid bodies with a frequency corresponding to the mass of moduli. In the sensitive band of AURIGA, some $100\,\mathrm{Hz}$ at around $1\,\mathrm{kHz}$, the expected signal, with a $Q=\tfrac{\triangle f}{f}\sim10^{6}$, is a narrow peak, $\triangle f\sim1\,\mathrm{mHz}$. Here the detector strain sensitivity is $h_{s}\sim2\times10^{-21}\,\mathrm{Hz^{-1/2}}$, within a factor of $2$. These numbers translate to upper limits at $95\%\,C.L.$ on the moduli coupling to ordinary matter $d_{e}\lesssim10^{-5}$ around masses $m_{\phi}=3.6\cdot10^{-12}\,\mathrm{eV}$, for the standard DM halo model with $\rho_{DM}=0.3\,\mathrm{GeV/cm^{3}}$.