The Effect of Water Depth on Muon Flux

The Effect of Water Depth on Muon Flux

Grace Gutierrez (Roosevelt High School), Finsam Samson (Troy High School)

Mike Niedballa (Wayne State University)

Gil Paz (Wayne State University)



This study was conducted to analyze the effect of water depth on muon flux. It built upon other research in this field, using larger scales of depth than was done in previous studies. Our hypothesis is that increasing the depth of the water that muons have to travel through will decrease the flux of the muons at the bottom, as the muons can be slowed and stopped by interacting with water molecules.



In this study, 3 large plastic bins with a maximum depth of 26 centimeters each were used. Four detector plates set in a column with a four-fold coincidence were used with these bins. The arrangement of these were as so (from top to bottom): plate, bin, plate, bin, plate, plate. Plateauing was conducted at first, and the four detector plates were calibrated accordingly. The study began with a control of 0 centimeter depth, and increased by 10 centimeters with every flux study conducted, until 70 centimeters. Two flux studies were run every day, with data collection running for at least 4 hours in each study.



              Our data shows an inverse relationship between muon flux and water depth. However, this relationship becomes unclear after .30 meters of water depth. The uncertainty is also graphed above. The depth of .40 meters had an uncertainty significantly larger than that of the other depths. One possible reason for this could be a power outage that occurred on the day that data was collected, as well as in subsequent days.


Meaning of the Data

              The collected data does support our hypothesis. In the first half of the experiment, muon flux decreased as depth increased, with low uncertainties. However, high uncertainties in the latter half of the experiment led to unclear results beyond .40 meters of depth.


Suggestions for Further Experimentation

              In future studies, efforts can be made to accurately collect the data from high values of depth. This is because it is unclear whether the relationship between muon flux and water depth is linear or exponential (decay). Additionally, other liquids could be tested as shielding to research the properties of substances that shield muons.




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