User:Lsimons
From MariachiWiki
[[1]]My part of lab one!
My name is Leah Simons. I was born in Bloomfield, New Jersey, but currently live in Pound Ridge, New York. I am a freshman at Stony Brook University, majoring in Biology and participating in the WISE program. Throughout high school I participated in a 3-year research program that allowed me to do my own project and present at presigious competitions across the country. I was a semifinalist in the Intel Science Talent Search and was also able to show my work in Albany and other competitions throughout Westchester County. I hope to go on to graduate school after graduating from Stony Brook, but I am unsure of what career I would like to pursue. I have always had a passion for marine science and animal science, so I may pursue marine biology or veterinary medicine.
In my free time I volunteer and intern at the Maritime Aquarium in Norwalk, Connecticut. When I am there I do research on harbor seals in Long Island Sound, and act as a docent to visitors at the aquarium. I have been working at the aquarium for the past four years and it has been an amazing help with my research and with getting experience in other fields of science. In my free time I like to hang out with my friends and my twin sister. When I'm not doing school work, I spend a lot of time outside with my parrot, Sweetpea, and often go to Fire Island or just down to the pond at my house to get some time alone.
(all blog entries are in the Discussion section)
[[2]]
CONCLUSION (lab #2)
The goal of this lab was to find the effect that materials had on the detection of cosmic rays and if placing various materials directly on scintillator detectors would change the rate of coincidences. By using the same set up with two scintillator detector system, we were able to separate the boxes and do trials using various materials of various densities. We had gone into the lab assuming that materials would change the amount of coincidences recorded due to their thickness and density slowing down, deflecting, or absorbing the cosmic rays. However, we had already considered the fact that we were indoors and any rays that we detected would have already passed through very thick materials such as the ceiling. So although we expected a change when utilizing other materials, we did not expect to see a large difference.
For our control, we separated the scintillator system by a distance of 61.4 centimeters with nothing in between the boxes. This would show us the affect that ordinary air has on cosmic rays, which is what has consistently been between the boxes throughout previous experiments. In a 5:00.3 minute trial, we recorded 1220 coincidences. This is approximately 4.06 coincidences per minute. We found the largest deviation from that control number when using the 1 centimeter thick piece of aluminum. In one trial of 5:00.3 minutes, and two trials of 5:00.2 minutes, we recorded 1129, 1051, and 1072 coincidences respectively. The average amount of coincidences passing through the aluminum in five minutes was 1084, a significant change from the control. Using less dense materials, we also detected changes similar to what we had expected to see. Using 0.6 centimeter thick tiles, we detected 1134 coincidences in 5:00.55 minutes. With 1.6 centimeter thick wood, we got 1125 coincidences in 5:00.3 minutes.
This data showed that materials affect the detection of cosmic rays. It also shows that various materials affect the detection to different degrees. The thick and very dense aluminum had the greatest deviation from the control, reducing the amount of rays detected by an average of 27.2 coincidences per minute. The tile reduces the occurrence of coincidences by approximately 17.2 per minute and the wood reduced it by 19 per minute. The data for the wood and tile did not coincide with the rest of our data as we would have hoped. Although the trials showed that bother the wood and the tile have a small effect on cosmic rays, it also showed that more cosmic rays pass through the much heavier and denser wood than the tile. This could be due to the thickness of the wood, which was 1.3 centimeters thicker than the tile. This disproves our theory that density of the object is the only factor that affects cosmic rays from passing through. It appears as though the thickness may be a controlling factor. This also shows that it may be the composition of the materials that affects the passing of cosmic rays.
In order to really get a hold on the interference of materials and whether or not that changes cosmic ray detection, we used a portable scintillator set which could be brought to various places throughout the building to measure the amount of coincidences. In order to show definitively whether materials of different kinds make a change in the amount of coincidences that occur, we took the portable scintillator to the basement of the physics building. With four floors blocking cosmic rays from passing, we did a trial of 30 minutes in the basement. We compared this to a 30 minute trial that we did on the top floor, where we usually conduct our experiments. The change in rate was undeniable. On the top floor we saw 3001 coincidences in 30 minutes, approximately 100.03 coincidences per minute. In the basement, with a plethora of materials of numerous densities, sizes, and shapes blocking rays, we got 656 coincidences in 30 minutes. That was approximately 21.87 coincidences per minute. This is a significant change in rate which could also be seen while watching the counter on the scintillator. On the top floor, the counter reset three times and counted very quickly. In the basement, the counter didn't even reset once, and the number rose at a slow rate. This evidence shows undoubtedly that materials do change the detection of cosmic rays. It required a large amount of material to see a very significant change in the rate of detection, showing that thinner, less dense materials would not have a large affect on cosmic ray detection if places between scintillator sets. Good absorbers of cosmic rays are thick, dense, heavy materials. This is probably due to the disruptive effect of the nuclei that the cosmic ray hits as it passes through the material. This causes it to slow down, which makes the equipment record it as a separate cosmic ray when it eventually hits the second detector. This effect could be seen when testing the 1 cm thick aluminum. Compared to the other mediums, it slowed the rate the most. Obviously whatever was used to make the physics building, such as large pieces of wood, various metals, and other materials make good absorbers of cosmic rays.
