We report the weakly interacting massive particle (WIMP) dark matter search results using the first physics-run data of the PandaX-II 500 kg liquid xenon dual-phase time-projection chamber, operating at the China JinPing underground laboratory. No dark matter candidate is identified above background. In combination with the data set during the commissioning run, with a total exposure of $3.3\times {10}^4\mathrm{kg}\text{day}$, the most stringent limit to the spin-independent interaction between the ordinary and WIMP dark matter is set for a range of dark matter mass between 5 and $1000\mathrm{GeV}/c^2$. The best upper limit on the scattering cross section is found $2.5\times {10}^{-46}{\mathrm{cm}}^2$ for the WIMP mass $40\mathrm{GeV}/c^2$ at 90% confidence level.

• Received 26 July 2016

DOI:https://doi.org/10.1103/PhysRevLett.117.121303