New experimental bounds on the contributions to the cosmological density parameter Ω from strongly interacting massive particles

Strongly interacting neutral massive particles ( SIMPs) have been proposed as candidates for dark matter, as the lightest supersymmetric particle, as a possible explanation for ultra high-energy cosmic rays, and as a dark matter solution to galactic structure problems. If bound to nuclei, SIMPs could manifest themselves as anomalously heavy isotopes of known elements. We analyze the results from a recent experimental search for SIMPs in a collection of gold and iron samples with various exposures to cosmic rays and to a SIMP component of dark matter. The samples included gold own on the NASA Long-Duration Exposure Facility, as well as geological samples and an iron meteorite. We show that the bounds on SIMPs from that experiment can be used to set nontrivial constraints on the SIMP contribution to the cosmological density parameter.