The Effect of Materials on Cosmic Rays
From MariachiWiki
Materials experiment
Date performed: April 19, 2006
Nicole Alimario
Zubaria Iram
Komal Majahid
Youstina Michael
Abstract
The objective of this experiment is to see how cosmic rays differ when exposed to different materials. Velocity is the main factor of cosmic rays that we are going to study. Will the speed of cosmic rays increase, decrease, or stay the same when exposed to high density or low density elements? By how much is the speed going to increase or decrease when exposed to these different materials? All these questions will be explored in this experiment. The basic idea was that if something is put in between the two scintillators then the cosmic rays would not pass as fast. The experiment was performed five times with two different controls. The results of this experiment would be lower compared to the control setup.
Theory
The counter counts the number of coincidences of cosmic rays between the two scintillators. However, if something is put in between the two scintillators, the number of coincidences or the speed of cosmic rays would change. We used three minutes as our time interval, because it didn't seem too long or too short, and it was enough for the class time we had to obtain the data. Our theory for this experiment is that when there will be something in between the scintillators the number of coincidences will be lower than when there is nothing in between.
Experimental
Materials
2 Scintillators
1 oscilloscope
Aluminum
Wood
Lead bricks
Cosmic Chris
Procedure
The control of this experiment will be the speed of cosmic rays without any materials added in the experiment, as we have done in the previous experiment. We set two scintillators at a fixed distance from each other and we use the oscilloscope to measure the speed of the cosmic rays. We keep the scintillators at the same disctance, but now we add different materials in between them, and again we measure the speed. We repeat the experiment with different materials added between the two scintillators. The control setup, the one without any material between the scintillators but with the same distance will be compared to the one with the setup that has the material in between, if the number of coincidences decreases then the material is blocking the cosmic rays, otherwise they are not. Therefore, it is the density of the object that is affecting the travel speed of the cosmic rays.
Data
Graph II
Thick materials decreased the number of coincidences. Our control experiment, in which no material was added between the two scintillators gave us 2528 coincidences. We then added different types of material i between, all of which changed the number of coincidences compared to our control. Wood seems to be the only material that did not change the numer of coincidences significantly. Data shows that the number of coincidences obtained by placing wood in between the two sintillators is 2520. Comparing the thick an think aluminum, we used as materials, we find that the thick aluminm decreased the number of coincidences to 2440 and surpisingly the thin aluminum increased the number of coincideces to 2575. The lead bricks decreased the number of coicidences significantly. The control lead brick had 1043 and the lead brick material decreased it to 971.
Conclusion
Conclusively, the materials with the most density and thickness blocked the greatest number of coincidences. When comparing the thin and the thick aluminum blocks, it was evident that the thick aluminum blocked the most coincidences. Also, when comparing all the materials used in this experiment, lead blocks were the responsible for the blockage of the greatest number of coincidences. The experiment done using cosmic chris, it was evident that the enormous amount of mass between the D Floor and the S Level blocked a great number of coincidences because on D Floor it took around 11 minutes for 999 coincidences to occur, whereas, on the S Level it took approximately 30 minutes for the same number of coincidences to occur. This proves that there are some materials which block cosmic rays more than the others. This depends on the thickness and density of the materials.
