| Abstract |
The primary goal of this project was to investigate simultaneous increases and decreases in radiation levels detected by Geiger-Müller counters in close proximity, despite the random nature of radioactive decay. The rise and fall in radiation seemed more like a pattern than random noise, suggesting the possibility of density fields. Having a better understanding of the type of random noise could be useful in calibrating radiation detectors such as X-Ray and Gamma Ray telescopes. I measured with five Geiger counters (FS2011, QA060, XH-901, BELLA, RAD 100) at different intervals. At 35-second intervals close together, the correlation here was low at <0.6 so I performed a speed read using shorter intervals, hypothesising that radiation fields were changing in density faster than our detectors could register. With 5-second intervals, keeping the same close distance, significant correlation was found between the counters. Far apart, no correlation was detected, suggesting the presence of small, transient hotspots or cold spots, passing by us in mere seconds. Radiation levels in the school ranged from 0.082 to 0.124 µS/h per room, averaging 0.101 µS/h, falling into the average 0.08-0.15 in Ireland. This was made into a detailed heatmap of the school. From 0.025 to 0.043 µS/h, the GM counter deviations highly affect the readings. Conclusively, three counters exceeded their claimed specs, meaning they could cause false positives of much higher readings. As the values I discovered are not uniform (gaussian), a Wiener filter would best eliminate the noise.
|