Dark matter search results from the commissioning run of PandaX-II

Abstract

We present the results of a search for weakly interacting massive particles (WIMPs) from the commissioning run of the PandaX-II experiment located at the China Jinping Underground Laboratory. A WIMP search data set with an exposure of $306\ifmmode\times\else\texttimes\fi{}19.1\text{ }\text{ }\mathrm{kg}\text{\ensuremath{-}}\text{day}$ was taken, while its dominant $^{85}\mathrm{Kr}$ background was used as the electron recoil calibration. No WIMP candidates are identified, and a 90% upper limit is set on the spin-independent elastic WIMP-nucleon cross section with a lowest excluded cross section of $2.97\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}45}\text{ }\text{ }{\mathrm{cm}}^{2}$ at a WIMP mass of $44.7\text{ }\text{ }\mathrm{GeV}/{\mathrm{c}}^{2}$.