Week+of+October+1-6,+2012

October 1, 2012
I arrived at Quarknet at about 3:45, and, having continued playing around with the Many Eyes graphs over the weekend, I had taken a few more Jing pictures on my laptop worth noting. Today, John, Alex, Dr. Loughran, and I discussed where our project will be heading as well as new ways of manipulating the data set on Many Eyes. The pictures I had previously taken (but not yet put into my wiki) as well as the images from above became more conclusive when I learned to highlight certain particles to see how they move and change when the axes are changed. In the following picture, I highlighted a line of particles on the Eta 2 vs. Mass graph in a line around 0 Eta on the Y axis.

Then, I switched the Y axis to Eta 1 to see where the trajectory of the selected points on the corresponding "half" of Eta fell.

From this image, it appears that the particles heavier than 40 GeV follow a linear trajectory, whereas the less massive particles scatter. I tried once again with a new set of points that worked even better. The graph below on the left shows highlighted points on Eta 1 vs. Mass; the graph on the right shows the same group of highlighted points on Eta 2 vs. Mass. The points greater than 40 GeV scatter even less here (more linear trajectory) than above. ==

I then used the same set of selected points from the second trial of Eta1 and Eta 2 vs. Mass, and switched the Y axis to Phi 1 and 2 in order to see if the linear trajectory noted in the Eta coordinates was vertical or not. I hoped to see that the selected points would concentrate around positive and negative 1/2 pi on phi 2 and 1, respectively, in order to show that the 40+ GeV particles were coming in from above in a straight line (vertically). The following pictures are Phi 1 vs. Mass and Phi 2 vs. Mass.

As I had hoped, the more massive particles that held interest as potential cosmic rays concentrated around positive 1/2 pi and negative 1/2 pi on either half of the Phi coordinate plane.

October 3, 2012
Today, Jason and I arrived at 3:30, and as we waited for the others to arrive, I summarized our work from Monday that he had missed. When John came, he got us started looking at histograms on the CMS eLab page. We looked at the dimuon 2011 data, and selected the graphs for mass, Eta, and Phi. The first step in analyzing the data was to narrow it down to around 0 Eta. We cut the graphs from -0.200 to 0.200 Eta; we knew that any potential cosmic rays would have entered the detector from this point. We then shifted our focus to the graph of mass. As a group, after some trial and error, we decided to change the scale of the graph to "log y" and we kept the bin width at 1. The most noteworthy feature of this graph is the huge jump at 40 GeV/c^2. From 30-40 GeV/c^2, there were no events, and then a spike at 40. Referring back to conclusions previously drawn through the Many Eyes graphs, this is the mass at which particles (presumably cosmic rays) began having a strictly linear trajectory, as opposed to the scattering of the other particles in the collision.

Next, we looked at the Phi graph. I noticed spikes between 1 and 2 and -1 and -2, so I changed the bin width to 0.1 in order to get a better idea of where the peaks were. The following picture shows a spike in events at both -1/2 pi and 1/2 pi. This shows an unusual number of particles interfering at these points--the same spots through which cosmic rays should travel through the detector.