Search for stable Strange Quark Matter in lunar soil

TL;DR

This study searched for strangelets in lunar soil using accelerator mass spectrometry, setting new upper limits on their concentration and flux, which informs theoretical models and cosmic ray observations.

Contribution

It provides the first experimental search for strangelets in lunar soil over a specific mass range, establishing the most sensitive flux limits to date.

Findings

No strangelets detected in lunar soil samples.

Excluded strangelet concentrations above 10^{-16} at 95% confidence for charge 8.

Set new upper limits on strangelet flux in cosmic rays.

Abstract

We report results from a search for strangelets (small chunks of Strange Quark Matter) in lunar soil using the Yale WNSL accelerator as a mass spectrometer. We have searched over a range in mass from A=42 to A=70 amu for nuclear charges 5, 6, 8, 9, and 11. No strangelets were found in the experiment. For strangelets with nuclear charge 8, a concentration in lunar soil higher than $10^{-16}$ is excluded at the 95% confidence level. The implied limit on the strangelet flux in cosmic rays is the most sensitive to date for the covered range and is relevant to both recent theoretical flux predictions and a strangelet candidate event found by the AMS-01 experiment.