Speaker
Dr
Chamkaur Chamkaur Ghag
(UCL)
Description
The LZ dark matter experiment will require an unprecedented low background rate within its fiducial volume, defining strict constraints on radioactivity from construction materials that is further mitigated through the combination of powerful self-shielding from liquid xenon, 3D event vertex reconstruction, and external veto detector systems. An aggressive screening campaign with cutting-edge instrumentation will be performed, prior to construction, to measure the trace levels of radioisotopes in materials and construct the experiments background model.
To provide sufficient sensitivity for LZ we have been re-developing the UK’s low-background screening capability. New ultra-low background HPGe and BEGe detectors have been installed at the Boulby Underground Laboratory, itself undergoing substantial facility re-furbishment, to provide high sensitivity gamma spectroscopy for all DMUK and 0vBB interests. Dedicated low-activity mass spectrometry instrumentation has been developed at UCL for part per trillion level contaminant identification to complement underground screening, complete U/Th assays, and meet throughput demands. Finally, radon emanation screening at UCL measures radon background inaccessible to gamma or mass spectrometry techniques. With gamma spectroscopy, mass spectrometry and radon screening to world-class sensitivities, the UK will deliver half of the radioactivity screening for LZ.
Primary author
Dr
Chamkaur Chamkaur Ghag
(UCL)
