Week+of+11-5+to+11-11

November 6th
I couldn't make it into QuarkNet early in this week or late last week because I was first slammed with schoolwork and then I went out of town, and couldn't work on my logbook during the vacation because my MacBook would not connect to the Internet. On Tuesday night, I finally had the chance to make up some lost ground and get in my last few graph explanations. I first chose to take a stab at explaining E sum vs. M1 parent rest frame. Although this graph looks interesting on first sight, further analysis seems to support that in fact there is not much of a relationship at all between these two variables. I talked with Dr. L a while ago about the trickiness of comparing data taken from largely different perspectives. To me, the most valuable thing this graph proves is that some graphs can truly just look interesting when in reality the things being compared are largely unrelated. Taking a closer look at the variables being compared shows how odd this comparison is. First of all, one variable (E sum) is observed from the outside of the system, while the other variable (M1 parent rest frame) is taken from the perspective of the parent particle. There's our first indicator that this comparison will be very hard to interpret. Next, we can see that one variable is a sum while the other refers to a specific particle. This can be a valuable relationship when the specific data is part of the sum, but in this situation, it is clear that M1 parent rest frame is not a significant component of E sum. Yes, the mass is indeed a component of energy, but when we move between parent rest frames and which particle we are referring to, this graph becomes largely meaningless. Next, I decided to tackle the graph of E1 parent rest frame vs. M1 parent rest frame. There are two main patterns shown at the same time in this graph: M1 parent rest frame is focused around 0.1 GeV, and particles of high E1 parent rest frame have a high M. This second trend is yet another thing that shows our assumption that cosmic rays are high mass particles, high energy particles. We know they are high energy particles, because of how massive the speed at which they travel is, and this would be shown from any measurement perspective in the detector. So, the fact that E1 parent rest frame seems to be directly correlated with M shows yet again that the high energy particles tend to have higher mass. As for the M1 parent rest frame always focusing around 0.1 while M raises similarly to E1 parent rest frame, after a discussion with Dr. L, I realized that this is showing that the rest mass of a muon. He previously knew that it was 0.1, and this was the first time he had seen a graph which showed those mass values concentrated around 0.1 for all energies. The final graph I will look at for this project is pz1 parent rest frame vs. pz1. This graph is a very interesting look at the difference between measurements from the parent rest frame and measurements from the outside of the detector. With this graph I noticed for the first time the arrow-drawing tool in Jing, and realized that it is very helpful in highlighting the trends we see in these graphs. Below is a copy of the graph above with arrows drawn on to accentuate where I thought the patterns were in this graph. It appears that there are a group of particles which had a pz1 parent rest frame of 0 but in fact did have pz1 of varying values. This makes sense because some of the particles must have gone on the same vertical trajectory as their parent particles, which means the parent particle wouldn't see any momentum but someone observing from the outside would. The other trend that stood out to me was the grouping of large particles on the line y=x, as shown with the angled arrow above. This is yet another place where we see that for what we figure to be the cosmic rays, the parent rest frame and the outside view return the same values because the detector artificially creates a parent rest frame when in fact there was no parent particle. With that, I am finished analyzing my ten interesting graphs. After a good chunk of work on Tuesday night, I finished at QuarkNet on Wednesday after asking Dr. L a question.

November 7th
Today I arrived at QuarkNet at 3:45 along with Jason, Grace, and Jeremiah. I started by sorting out a bit of confusion in part of the post I mostly completed last night. Then, Dr. L had us move on to commenting on each other's ten graphs in order to possibly enhance each other's understanding of the trends in the data. We spent the next hour or so delving through each other's logbooks. Then, the group moved into an Excel project with the CMS data while I broke off into a completely different direction and started toying around with MATLAB. It turned out I didn't actually have the chance to try out MATLAB because there was no available computer where I could successfully use it. So, I sat in on the Excel debriefing. Dr. L showed some basic Excel skills, such as creating columns and using formulas. He explained how to very quickly calculate large volumes of data by referencing cells and copying formulas rather than typing in individual numbers and calculations. He also showed how to sort columns by numbers or alphabetical order, and he showed how to mass-copy and just generally deal with the huge amount of data in the CMS dimuon data. Interestingly, he discovered that the sort function can only handle 1000 items at a time, which is far fewer than the number of rows in the dimuon data, but is still a substantial set of data. I finally got my hands on a computer with MATLAB, but didn't have very long to begin fooling around. I checked out the "Desktop Basics" and "Matrices and Arrays" tabs of the "Getting Started with MATLAB" page (which can be found by searching for the title in the "Search Documentation" box. The functions of MATLAB I learned from these were essentially calculator functions. These functions in the Command Window are a slightly modified version of many of the things we can do on graphing calculators. I left QuarkNet at 5:45