There is a figure that the Deep Underground Science and Engineering Lab (DUSEL) guys were bandying about back when the NSF was making its initial decision on which underground facility would best suit an underground neutrino detection lab, maybe seven years ago. The figure showed Homestake mine was the deepest candidate with operational facilities at 8,000 feet below the ground surface. This was considered favorable because the deeper the lab was buried the more cosmic rays would be filtered out. This was good because those pesky cosmic rays interfered with the neutrino detectors (the neutrinos were not affected by the earth above).
My question is how the topography of the ground and the density of the ground change the shielding properties of the earth above the neutrino lab? I know this work has been done already to some extent. I had a conversation with Bill Roggenthen who told me Wick Haxton at U. of Cal Berkely did the theoretical work and Nicolai Tolich at U of Washington looked at the topography issue. But I still don't think anyone has looked in detail at the properties of the rock surrounding the lab, which could impart a directional shielding effect.
Talking to my friend Mark, who is helping with a little experiment called LUX at the DUSEL, he says the important thing to look for is how many Muons can be shielded with depth. I told him this would be a problem since I did not believe in Muons, but he insists they really exist. So, if anyone is interested, I want to look into the question and you are welcome to join me. It is work that is likely already done or could be tested in a few years when the lower levels of the lab are developed and the muon background is directly measured. But it is a fantastic question and probably will impart lots of edumacation in the process.
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