



01697nas a2200181   4500008004100000245007000041210006900111260001400180490000800194520115900202100002301361700001501384700001901399700002001418700001901438700002101457856003701478       2020                        eng d00aSearch for composite dark matter with optically levitated sensors0 aSearch for composite dark matter with optically levitated sensor  c11/2/20200 v1253 a<p>Results are reported from a search for a class of composite dark matter models with feeble, long-range interactions with normal matter. We search for impulses arising from passing dark matter particles by monitoring the mechanical motion of an optically levitated nanogram mass over the course of several days. Assuming such particles constitute the dominant component of dark matter, this search places upper limits on their interaction with neutrons of αn&le;1.2&times;10&minus;7 at 95\% confidence for dark matter masses between 1--10 TeV and mediator masses mφ&le;0.1 eV. Due to the large enhancement of the cross-section for dark matter to coherently scatter from a nanogram mass (&sim;1029 times that for a single neutron) and the ability to detect momentum transfers as small as &sim;200 MeV/c, these results provide sensitivity to certain classes of composite dark matter models that substantially exceeds existing searches, including those employing kg-scale or ton-scale targets. Extensions of these techniques can enable directionally-sensitive searches for a broad class of previously inaccessible heavy dark matter candidates.&nbsp;</p>1 aMonteiro, Fernando1 aAfek, Gadi1 aCarney, Daniel1 aKrnjaic, Gordan1 aWang, Jiaxiang1 aMoore, David, C.  uhttps://arxiv.org/abs/2007.12067