First, LZ construction is continuing to progress at a fast pace. The central component, the `Time Projection Chamber’ completed assembly and insertion into the cryostat, you can see some photos of this process here.

And second, the 3He/4He dilution refrigerator for the helium side of our efforts (`HeRALD’, Helium Roton Apparatus for Light Dark Matter) arrived and was successfully installed in our lab, the culmination of a multi-year design and assembly process (photo to the right). Everything about the fridge is state-of-the-art. Soon we’ll be running several types of experiments in this fridge at mK temperatures.

Looking forward to some amazing science with both these instruments.

These are exciting times for LZ, as major components are arriving on site in South Dakota, and the first stages of detector assembly are taking place. These major pieces include the cryostat vessels, the large acrylic vessels that will surround the cryostat, and many inner workings of the xenon-based detector itself, including the arrays of photomultiplier tubes. For more, see the links below.

recent article
LZ twitter feed

We recently posted a general description of the 4He-based detector concept, including realistic estimations of backgrounds and resulting sensitivities. Now, on to making this happen! Next steps in our lab: installing the dilution fridge (March) and optimizing the methods used to keep the upper detector platform free of 4He superfluid film (next few months into the summer).

arxiv:1810.06283

We spent some time recently moving everything into two beautiful laboratory spaces in the new Physical Sciences Building.

https://www.umass.edu/dcm/psb

We recently posted a description of a calibration technique first used in LUX relying on mixing a calibration activity with the bulk liquid xenon detector material. Our group is working to build on this success and supply similar calibrations for the upcoming LZ experiment.

arxiv:1708.02566

arxiv:1703.09144