Ultraheavy dark matter search with electron microscopy of geological quartz
Reza Ebadi, Anubhav Mathur, Erwin H. Tanin, Nicholas D. Tailby, Mason C. Marshall, Aakash Ravi, Raisa Trubko, Roger Fu, David F. Phillips, Surjeet Rajendran, Ronald L. Walsworth
Abstract
Self-interactions within the dark sector could clump dark matter into heavy composite states with low number density, leading to a highly suppressed event rate in existing direct detection experiments. However, the large interaction cross section between such ultraheavy dark matter (UHDM) and standard model matter results in a distinctive and compelling signature; long, straight damage tracks as they pass through and scatter with matter. In this work, we propose using geologically old quartz samples as large-exposure detectors for UHDM. We describe a high-resolution readout method based on electron microscopy, characterize the most favorable geological samples for this approach, and study its reach in a simple model of the dark sector. The advantage of this search strategy is twofold; the age of geological quartz compensates for the low number density of ultraheavy composite dark matter, and the distinct geometry of the damage track serves as a high-fidelity background rejection tool.