Theoretical formula for the cosmic-ray muon attenuation coefficients of Pb, Cu, Zn, and Al

Abstract

The attenuation coefficients of cosmic-ray muons through metal plates were theoretically determined. Three methods (A, B, and C) were proposed by the researchers using the experimental data of count rate which was obtained from the detection of cosmic-ray muons through metal plates of different thicknesses. Method A was applied to Pb, Cu, Zn, and Al, whereas Methods B and C were applied to Pb only. The proposed A and B methods were based on ignoring the detected count rate produced by the shower of electromagnetic cascades to obtain the attenuation of cosmic-ray muons. The values and the formula of the radiation length of metals were used in Method A to obtain a theoretical formula to measure the cosmic-ray muon attenuation coefficients. The results showed consistent behavior with the atomic number, mass number, and mass density. In Method C, the penetrating muon is assumed to generate many sources of photon-electron cascades at every collision. The result was successful in describing the theoretical count rate behavior and to implicitly determine the muon attenuation.

Using Cosmic Watch Detectors to Measure the Attenuation Coefficient of Cosmic Muon in the Lead Bricks

“…Compared to ours, they have used the decaying of muon to calculate the value. This may lead to some distinction [9].…”

“…Compared to ours, they have used the decaying of muon to calculate the value. This may lead to some distinction[9].The statistical error for total count each are 6.1474×10−3, 5.6184 ×10−3, 5.4587×10−3, 6.0068 ×10−3. There are some systematic errors that we need to take into ac-count: temperature variations and pressure.…”