I’m not sure if this is one of those things that only a mother could love, but my M.S. thesis (“An Extended Study on the Effects of Incorrect Coordinates on Surface Detector Timing”) is submitted and will be defended next week. This fellow, alias “Figure 6,” is the most colorful and hence cutest of the graphs.
Yes, I just called a bunch of Gaussian distributions cute. Shut up!
For anyone who actually wants an explanation here, what I basically did for my M.S. thesis was take GPS units similar to those in the Pierre Auger Observatory and test to see what would happen if the position got increasingly wrong on them. In addition to position data a GPS unit also gets timing from satellites, making them a very accurate clock, and accurate timing is exactly what you need when you’re trying to track a shower of particles hitting the ground at nearly the speed of light. Literally every nanosecond counts!
Normally in the field we just set the position to make the timing data more accurate (because the GPS won’t have to worry about finding where it is and what time it is with each cosmic ray strike), but sometimes that’s off for a myriad of reasons. So the above graph is the product of modeling that: one GPS “clock” was allowed to find the correct position/time and the other was given an increasingly incorrect position, and the difference between the two tells you what happens when you actually have an incorrect position in the field. Then when you add up all those differences over the time it took to collect the data (five days was typical, with one data point each second) and plot the distribution, you discover that the higher you go the quicker you receive the signal. Just what you’d expect when a GPS is getting signals from overhead satellites really: when you go higher up you’ll receive the signal just a little bit quicker.
And that, ladies and gents, is what science looks like. Thank you, I’ll be here all week.
