The Effect of Concrete and Steel Shielding on Cosmic Ray Muon Flux

The purpose of this experiment was to determine the effect of a combination of concrete and steel shielding on cosmic ray muon flux. Concrete is known to be a semi-effective shield, while iron is known to be a highly effective shield. The types of steel tested were standard steel and galvanized (zinc-plated) steel, tested at the same thicknesses. The results obtained from this research were the percent decrease in muon flux for the two types of steel that were tested with the concrete. The concrete was stacked to increase the thickness of the shield, and a 0.96 mm layer of steel was placed between every 4 cm concrete block. To determine the percent decrease for both the concrete and standard steel shield and the concrete and galvanized steel shield, varying thicknesses of the concrete were tested and a linear regression t test was performed to confirm that the data follows a negative linear pattern. Then, the slope calculated from the t test was used to determine the percent decrease in muon flux from 0 m shield thickness to 47.6 cm shield thickness.

The results of this experiment demonstrated that adding layers of steel between the concrete blocks decreased the number of muons that would pass through the shield. 44.2% of muons were shielded by concrete and standard steel at a thickness of 47.6 cm. The results of the zinc-plated steel trials were inconclusive.

The information gathered from this research is important to physics research because it can be used to protect sensitive dark matter experiments from muon interference. This research can also reveal properties of muons, which expands on current knowledge of particle physics.

Research Conducted By:

Emily Elizondo
Sterling Heights High School

Jillian Schell
Sterling Heights High School