Design of the ZEPLIN II Detector

We will discuss the detailed design of the ZEPLIN II detector, to be installed in the Boulby Mine, UK, for the direct detection of WIMP dark matter. Based on the liquid xenon (Xe) R&D work carried out at CERN by UCLA and Torino, which measures ionization and scintillation simultaneously in two-phase Xe, ZEPLIN-II will have very high radioactive-background rejection efficiency. We will describe in detail the technology and the design considerations. The ZEPLIN-II detector will be operated in collaboration with the UKDMC, Columbia University, and CNR Torino.