Calculating the Average Speed of a Cosmic Ray Muon using a Scintillating Cosmic Ray Muon Detector

Our research this summer was divided in to two parts:  cosmic ray muon detector experiments and neutrino physics.  Abstracts for both projects are attached.

The Velocity of Muons in Direct Relation to an Indoor Environment vs. an Outdoor Environment

Jacob Travis (Woodhaven High School), Joseph Kovalchik (Roseville High School)
 
Mike Niedballa (Michigan Collegiate High School)
 
Gil Paz (Wayne State University)

 

The purpose of this experiment is to test if a substantial amount of matter could affect the velocity of a muon as it travels through space. We tested this idea out by collecting data from the scintillators on a wooden shelf that stands 2.175 meters tall, with an average of a 0.725 meter difference in length between each scintillator paddle. The data collected from the paddles is analyzed from the trials the detector runs from both inside the building and outside the building. A time of flight study is ran on both groupings of trials: inside data and outside data. We found that there is no real significant difference in the velocity of the muon comparing the velocity of the muon within the time of flight studies of the indoor and the outdoor data. Possible conclusions that could explain our results could include the possibility that the muons that travel through the building are travelling at such a high velocity that the building can't offer enough impedance to significantly change the muon's velocity. Future studies that could possibly be ran and investigated includes utilizing thicker buildings to run studies in, or running the detectors in a wide open field so the muon’s velocity wouldn’t be hindered by structures or matter farther away from the detectors.

 

Effects of Varying Water Depths on Shielding Muon Flux

Allen Diao (Troy High School), Ben Zeman (Groves High School)

Mike Niedballa (Michigan Collegiate High School)

Gil Paz (Wayne State University)

 

The purpose of our experiment was to determine the relationship between depths of water and muon flux. We wanted to see if water could be effectively used to shield detectors from muons. To run the experiment, we set up detectors above and below coolers of water at different depths of water. The data was recorded for periods of over seven hours and each depth had only one trial due to time constraints. We recorded data from all four detectors with a coincidence level of 4, so each muon had to hit all four detectors to be recorded as an event. Therefore, they traveled relatively straight and passed through the water, making our results more accurate. The results of our study saw a steady decline in muon flux as water between the detectors was increased to 85 cm. After testing the various depths of water, we concluded that water does cause a statistically significant difference in muon flux by running an ANOVA test on our data. As a result, it can be reasonably assumed that water is able to shield against low energy muons.

Time of Flight Studies

Dylan Beasley (Huron High School), Mary Zylinski (Utica Academy for International Studies)

Mike Niedballa (Michigan Collegiate High School)

Gil Paz (Wayne State University)

 

            This experiment is to find the panel layout that gives the most accurate time of flight of muons. We set up three different layouts of panels and veto panels, tested all at three different heights, and ran data collection to get similar hit counts for each height. Data shows too large of discrepancies for each set-up, thus none are viable to use. Most “accurate” in this case, however, is standard 2-panel set-up which had the smallest increase of velocity at 13%. Further improvements could be made with more time to collect more data and run more trials as well as obtain a program that can segment data.

The Effects of Steel Shielding on Observed Muon Flux

Kurt Huebner (Grosse Pointe South High School), Phillip Popp (The Roeper School)

Mike Niedballa (Warren Collegiate High School)

Dr. Gil Paz (Wayne State University)

The purpose of our research was to determine if sheet metal of widths ranging from 1/16th of an inch to ¼ of an inch (in 1/16th of an inch increments) would have a shielding effect in the detection of muon flux. The experiment was performed by using two pair of scintillator paddles with steel plating in between. We found that a quarter inch of steel was effective in reducing the control flux of 479 events/minute/meters2 to 466 events/minute/meters2. Reducing the shielding yielded diminishing returns, to the point where 1/8th of an inch plating gave statistically insignificant results. These results suggest that steel is capable of being used as a shield from cosmic ray. This research could be continued by testing a larger variety of steel plating thicknesses, and even testing different metal’s effectiveness in cosmic ray shielding.

The Effect of Angle of Elevation on Muon Flux

Sudheshna Gullanki (Troy High School) and Tanner Allen (Paul K Cousino High School)

Teacher Mentor: Mike Niedballa (Michigan Collegiate High SChool)

Research Mentor: Gil Piz (Wayne State University)

 

The purpose of our research is to study and experiment the correlation between the angle of the cosmic ray detectors and the count of incoming muons. We believe that the more perpendicular the stacked detectors are to the earth, the more muons will be detected, inversely the more horizontal the stacked detectors are to the earth the less muons will be detected.

 

We tried to keep the data as accurate as possible. We collected data more approximately eight hours for each angle of elevation. We never never changed the position of the placement of the detectors. We also used many different kinds of graphs to prove our experiment correct. We made a flux study to compare results between the detectors. A box plot was made to show a standardized way of displaying our results of minimum, first quartile, median, third quartile, and maximum. Then we conducted an ANOVA test to statistically analyze the difference between data. Lastly we also mathematically verified our experiment’s validity using a unique theoretical equation for predicting muon flux at a given angle of elevation written from scratch.

 

Our hypothesis was accepted. We hypothesized that angles of elevation closer to vertical would have higher rates of directional muon flux, and they did. However, why does this work? Muons are typically formed by cosmic ray collisions with particles in the atmosphere about 10-15km from the Earth's surface. Since they are traveling so quickly (.98c), Einstein's principles of relativity allow them to reach the surface of the Earth in relatively large numbers; almost 4.9% of muons at that altitude and that speed reach the surface of the Earth before decaying. However, when the angle of elevation shifts away from vertical, the distance muons must travel to reach the surface from any given altitude increases exponentially. For example, if all muons in a given trial decayed at 15 km, vertically aligned muons would only travel through 15 km of atmosphere and reach the Earth only a couple units of mean lifetime later, whereas muons traveling from the horizon have to cross almost 450 km of atmosphere before reaching the detectors, spending about 130 mean lifetimes.

Shower Studies

Frank Vella (Western International High School)

Rumana Begum (Hamtramck High School)

Mike Niedballa (Michigan Collegiate High School)

Dr. Gil Paz (Wayne State University)

1 July 2016

            Our project was based on shower studies. The purpose of our project was to find the most efficient way to detect cosmic ray shower events. Our first method was setting our detectors 4 meters apart. This is the format that we believe to capture the least amount of events in the highest amount of time.  After that, we set our detectors into what would be our smallest area, only 0.3 meters apart, the format we believe to be the most efficient. Then we enlarged the area by 1.4 meters. At last, we increased the area once more. We set each paddle 2.4 meters apart. Our hypothesis was correct! Indeed, the smallest format detected the highest amount of events in the shortest amount of time. The smallest area detected 373 events in approximately 4.85 hours while the large took 64.63 hours. The paddles that were set 1.7 and 2.4 meters apart detected 373 events in 30 hours and 58.5 hours. By learning this, we now know the most efficient format to perform a shower study.

Speed of a Muon

Mohit Bansil(North Farmington High School) & Alex Johnson(Woodhaven High School)

Teacher Mentor: Mike Niedballa(Michigan Collegiate High School)

Research Metor: Rob Harr(Wayne State University)

Our experiment is designed to find the speed of a muon. We set up 4 stacked detectors and recorded the time that a muon took to pass through the detectors and used it to calculate the average speed. The final results showed that the average speed of a muon is about .95 times the speed of light. The accepted speed of a muon is .996 times the speed of light, which means our data had a 4.6% error.  This could easily be caused by unknown variables such as multiple muons hitting or delay times between the muon passing and the photon being detected.

Surface Area vs. Rate of Shower Events

Christopher Coulter(Woodhaven High School) and Nathaniel Lee(Roeper Upper School)

Teacher Mentor: Mike Niedballa(Michigan Collegiate High School)

Research Mentor: Robert Harr(Wayne State University)

The purpose of this experiment was to determine the relationship between the rate of cosmic ray showers with varying surface area of detection. We used the 6600 CRMD equipment from QuarkNet to conduct the experiment. We placed detectors in a square configuration and varied the side length of the square to change the surface area of detection. The smaller area trials picked up small showers and larger showers, so the resulting data was the integral of the rate of showers with respect to area. This is why we had to take the negative derivative of the best fit line of the original result to find the actual rate of shower at a specific area. The ultimate results supported the idea that smaller showers are more common because the negative derivative showed an inverse relationship. In the future this experiment could be tested with a greater distance between detectors and run for longer periods of time to possibly determine the average surface area of cosmic ray showers. 

How Angle Affects Muon Flux

Pranathi Locula(Troy High School) and Sadia Farha(Frontier International Academy)

Teacher Mentor: Mike Niedballa(Michigan Collegiate High School)

Research Mentor: Rob Harr (Wayne State University)

The purpose of our research is to determine the effect of changing the angle of the cosmic ray detectors on muon flux. By changing the angle at which the detectors are pointed, we are changing the amount of atmosphere that the muons have to pass through and the direction that the muons have to travel in in order to hit the detector. Thus, our hypothesis is that as we increase the angle from horizontal the muon flux will increase. To change the angle at which the detectors are held, we used a wooden telescope with racks to place the detectors in. We secured the telescope at a different angle for each study and then analyzed our data. After completing our research, we found that as the angle  increased, the amount of muon flux also increased. We concluded that this is because at a lower angle, the muons have to pass through more atmosphere, making it harder for them to reach the detector, resulting in less flux. At a higher angle, the muons have to pass through less of the atmosphere to reach the detectors, resulting in more flux.