Liquid xenon purification system. (IMAGE) DOE/SLAC National Accelerator Laboratory Caption Xenon purification system at SLAC. The two central columns are each filled with almost half a ton of charcoal, which is used to produce ultra-clean xenon for the LUX-ZEPLIN (LZ) dark matter experiment. Credit Jacqueline Ramseyer Orrell/SLAC National Accelerator Laboratory Usage Restrictions Use credit. License Original 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.