China-Japan Collaboration (IMAGE) Chinese Academy of Sciences Headquarters Caption The China-Japan collaboration placed new water Cherenkov-type muon detectors under the existing cosmic-ray air-shower array in 2014. These underground muon detectors can suppress 99.92% of cosmic-ray background noise. Credit Image by IHEP Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.