An Analysis of Muon Flux from Angle Variation of the QuarkNet Cosmic Ray Detector

TL;DR

This study measures how muon flux decreases with angle using the QuarkNet Cosmic Ray Detector, providing insights into detector calibration, flux modeling, and demonstrating the feasibility of classroom-based cosmic ray experiments.

Contribution

First experimental quantification of muon flux angle variation with the QuarkNet detector, including flux modeling and validation of classroom science experiments.

Findings

Muon flux decreases with increasing angle from zenith.

Estimated flux model exponent n=1.39±0.01 for angles <75°.

Demonstrated feasibility of conducting cosmic ray experiments in classrooms.

Abstract

We present one of the first cosmic ray muon flux-angle variation experiments on the QuarkNet Cosmic Ray Detector (QNCRD). We first describe QNCRD and its calibration. The main focus is then quantifying muon flux decrease as a function of angle from the zenith. The angle of counters of QNCRD were incremented 15 degrees on average every $3.1$ days over the range of 0 degrees to 90 degrees for a period of approximately one month. Results showed that as the angle of the detector increased from the zenith, muon flux decreased, which agrees with previous studies. An estimate for the flux based on the model $I(\theta)=I_0cos(\theta)^n$ had an exponent value of $n=1.39 \pm 0.01$ for $\theta < 75$ degrees, an underestimate of values in other literature. These findings provided a reasonable, although not entirely accurate, estimate for the value of $n$ considering the duration of the study and sensitivity of the instrument. Our results constrain the accuracy of QNCRD and provide a source for future long-term experiments. This study also demonstrates the feasibility of conducting science experiments in high school classrooms, increasing science accessibility.