XMASS 1.5: The next step in Kamioka, Japan. Issue 4 (May 2016) - Xu, Benda
Abstract: The XMASS program at Kamioka Observatory uses self-shielding liquid xenon scintillation detectors to search for dark matter, double beta decay, and ultimately low energy solar neutrinos. For the next stage in this program, we envision building alt fiducial volume detector: XMASS 1.5. The upgraded detector design reflects our experience with the current XMASS detector. The new design requires PMTs that can intercept light traveling parallel to the inner detector surface. The first batch of these new PMTs has passed the performance verification test.