Dr. Priscilla Cushman

But that's what we're looking for.

Imagine that you are standing in the middle of a large stadium and then the nucleus would be like putting a little grape

down in the middle, and all the electrons are out at the edges of that stadium.

So for a dark matter particle that needs to get very, very close to that grape, there is a ton of open space for it to go through.

And that's our main problem is that there's a lot of dark matter particles, but as they move through us and through

the Earth, and also through our detectors, we have a hard time detecting them because they mostly just pass through.

Obviously, the more detectors you have, the more nuclei you have, and the longer you wait to see an interaction, the more likely you are to see one.

So that's what drives the need for a larger and larger detector, or in our case, very

sensitive detectors that can look at the very lowest and tiniest energy depositions.

Well, there are actually two reasons.

First of all, we are better able to distinguish that deposited energy from the particle interactions we care about, right, from the generalized thermal energy of the surrounding atomic nuclei.

But also the crystals are outfitted with superconducting sensors, and they only work when they're extremely cold.

Well, how cold does it have to be?

So for super CDMS, the temperature at which our sensors can operate is somewhere between 20 and 40 millikelvin.

The exact temperature depends on the TC or transition temperature of the tungsten sensors and where they go superconducting.

So let's take 30 millikelvin.

That is about 0.03 degrees above absolute zero.

Wow.

It's actually not unusually cold.

It is unusually cold for humans, I suppose.