Unidentified falling objects in the LHC as dark matter signals

TL;DR

This paper explores the possibility that some UFOs observed at the LHC are caused by axion quark nuggets, a dark matter candidate, which could generate detectable acoustic signals when passing near the collider.

Contribution

It proposes a novel hypothesis linking UFOs to axion quark nuggets and suggests the LHC could detect these dark matter particles through acoustic signals.

Findings

Approximately 1-10% of UFOs could be caused by AQNs.

Detection of three correlated UFOs could confirm AQN signals with high confidence.

LHC can act as a broadband acoustic detector for dark matter AQNs.

Abstract

Unidentified Falling Objects (UFOs) refer to sporadic beam losses observed during LHC operation. The prevailing explanation is that micrometer-sized dust particles released from the beam screen produce beam losses through interactions with the protons. However, the release mechanism of these particles remains unknown. We propose that roughly $(1-10)$% of UFOs may be caused by axion quark nuggets (AQNs), macroscopic dark matter (DM) candidates with masses of order $(5-1000)\,$g. The AQN model naturally relates the dark- and visible-matter abundances ($\Omega_\mathrm{DM}\sim\Omega_\mathrm{visible}$) and provides a mechanism for generating the baryon-antibaryon asymmetry, with DM composed of both matter and antimatter AQNs. When passing underground within approximately 100km of the LHC, an antimatter AQN generates acoustic waves strong enough to trigger multiple UFO events within $2\,$s. If three correlated UFOs (placed at different locations along the LHC ring) are detected, the signal-to-noise ratio can exceed 5 across the entire allowed AQN mass range for a measurement time of about 360 hours. Practically, the LHC can serve as a large broadband acoustic detector for AQNs.