Evaluating the Effects of Differing Elevations on the Cosmic Ray Detector

1. Evaluating the Effects of Differing Elevations on the Cosmic Ray Detector Chris Allen, Jeff Allen, Drew Kemp-Baird, Nick Ross, Lucas Strakowski Anderson High School, Cincinnati, Ohio MATERIALS AND METHODS RESULTS BACKGROUND • What are cosmic rays? • Particles that come from outer space. • Only secondary cosmic rays reach sea level. • These rays are mostly from the sun. • Solar cosmic rays are low in energy. What is a cosmic ray detector? A cosmic ray detector is a device that records instances in which cosmic rays collide with the detector. The detector can be set up in different ways, such as with two detectors on top of each other. This allows for more precise data, as the detector can be calibrated to only record instances that align with both panels of it. This data is saved, uploaded to the QuarkNet website, and further analyzed. • Materials: • Two cosmic ray counters stacked on top of each other • Laptop, cart, and other materials required for data to be taken • Methods: • Began tests in Room 105 as a control; we would use the data from the control to determine if any change in cosmic ray detection was evidentbased on day-to-day changes in the flux. • Moved cosmic ray detector to different heights to determine whether or not a change in height and surface amount would cause the amount of cosmic rays detected to vary, making sure that the same voltages were measured at all times • We used the following rooms, from highest to lowest in elevation: • Chorus Music Library • Band/Orchestra Music Library • Wrestling Room Closet • Tested the control in Room 105 again to see if any difference is noticed • Analyzed the data to get flux graphs • Compared the control results with the variable results to determine if a change in location and elevation results in a significant change in the amount of cosmic rays detected The results from a control study using the 5509 detector performed in Room 105 are the data we used as our control group. Our data collected in Room 105 using the 6228 detector showed an average of 2322 events/m²/60sec, and our control averaged 792 events/m²/60sec. The data collected using the 6228 detector in the chorus library (highest in altitude) averaged 2165 events/m²/60sec, while the control running in room 105 averaged 728 events/m²/60sec. The data collected in band/orchestra library (midway in altitude) averaged 1946 events/m²/60sec, while the control averaged 767 events/m²/60sec. The data collected in the wrestling room closet (lowest in altitude) averaged 1371 events/m²/60sec, while the control averaged 728 events/m²/60sec. We then found the percent of change by dividing the average count rate found by the experiment by the average count rate of the control. (ex: divide the chorus library count by the control count which was 2165/2322 (7%) and the control count from the chorus room by the control count in room 105 which was 728/792 (8%).) The greater change in percentage between the control count rate and the experiment count rate shows that the counts detected in the experiment decrease. For the band/orchestra library the average count rate divided by the control count rate was 16%, while the control was 3%. The average count rate from the experiment divided by the control count rate was a percentage of 41%, while the control percentage was 8%. The large differences between the percentages show that less cosmic rays reach the detector when it is located in lower levels of the building compared to when it is located in a higher level. PURPOSE AND HYPOTHESIS The purpose of our experiment is to find the presence and amount of collected cosmic rays based on which floor of a primarily concrete building the detector is located. By changing the floor the detector is on we can see the effect that the building has on cosmic rays. The hypothesis is that the floor will stop or slow down the cosmic rays, yielding a result in which the detector on lower floors of the building will receive less cosmic rays. CONCLUSIONS Using the results from the experiment, we concluded that there is a difference between the cosmic ray events of the experiment and the events of the control. Therefore, our hypothesis for the experiment was proved to be true: the cosmic ray count on the building’s lowest level received the least number of hits whereas the cosmic ray count on the building’s highest level received the most hits. The event hits in the Chorus Library remained relatively close to the control because the quantity of material above the Chorus Library and Room 105 is about the same. The altitude therefore affects the number of hits mainly because the cosmic rays become slowed or stopped by the interaction with materials of the building above each room. Also, a cascading effect may occur in which a particle in the building materials, such as lead, cause a high energy particle to break up into many smaller, low energy particles upon contact with the building. In these instances, the count rate is decreased as the building materials above the detector is increased because some particles either never reach the detector or the particles have such low energy that it doesn’t affect the count rate. Experiment Using 6228 counter Control Data Control Data gathered from 5509 Experiment Using 6228 counter Band/Orchestra Library Data Control Data gathered from 5509 Rm: Chorus Library Avg events: 2165 (percent chg: 7%) Avg events from control: 728 (percent chg: 8%) Change in Percent: 1% BIBLIOGRAPHY http://www18.i2u2.org/elab/cosmic/home/splash.html Experiment Using 6228 counter Chorus Library Data Control Data gathered from 5509 Experiment Using 6228 counter Wrestling room closet Data Control Data gathered from 5509 Rm: Band/ Orch Library Avg events: 1946 (percent chg: 16%) Avg events from control: 767 (percent chg: 3%)Change in Percent: 13% Rm: 105 (Control) Avg events: 2322 Avg events from control: 792 Rm: Wrestling Room Avg events: 1371 (percent chg: 41%) Avg events from control: 728 (percent chg: 8%) Change in Percent: 33%