Detecting Dark Blobs

TL;DR

This paper explores the possibility that dark matter forms large composite blobs due to self-interactions, proposing new detection strategies that utilize existing experimental techniques across multiple platforms.

Contribution

It introduces the concept of dark matter forming large composite blobs and identifies how current detectors can be adapted to search for these objects.

Findings

Cosmological and astrophysical bounds on dark blobs are established.

Existing detectors like XENON, LIGO, and CASPEr can potentially detect dark blobs.

Parameter space for detectable dark blobs is identified.

Abstract

Current dark matter detection strategies are based on the assumption that the dark matter is a gas of non-interacting particles with a reasonably large number density. This picture is dramatically altered if there are significant self interactions within the dark sector, potentially resulting in the coalescence of dark matter particles into large composite blobs. The low number density of these blobs necessitates new detector strategies. We study cosmological, astrophysical and direct detection bounds on this scenario and identify experimentally accessible parameter space. The enhanced interaction between large composite states and the standard model allows searches for such composite blobs using existing experimental techniques. This includes the detection of scintillation in MACRO, XENON and LUX, heat in calorimeters such as CDMS, acceleration and strain in gravitational wave detectors such as LIGO and AGIS, and spin precession in CASPEr. These searches leverage the fact that the transit of the dark matter occurs at a speed ~220 km/s, well separated from relativistic and terrestrial sources of noise. They can be searched for either through modifications to the data analysis protocol or relatively straightforward adjustments to the operating conditions of these experiments.