Tuesday, July 24, 2007

Research in High-Energy Astrophysics

I have finally finished the process of moving and returned to Cleveland, the land of old industry and flat terrain, but not all is lost because I have begun working on my senior project! Hooray! I am working with the High-Energy Astrophysics (HEA) group on campus that I started working on last summer, and while the project is not quite looking for aliens, it should be fun.

The (main) current focus in HEA has to do with high energy cosmic rays. In the early 90s, a group in Utah detected a subatomic particle from deep space (aka a cosmic ray) which had energies greater than fifty Joules. (For comparison, 50 J is about the amount of energy used in pitching a 60 mph baseball. Except a baseball is a lot bigger!) This discovery excited everyone greatly because it was theoretically impossible for such energies to be observed, and no one was really sure how these particles were given such huge energies or where they came from. As it is estimated that only one of these particles hits a square kilometer in a century, this did not really help in figuring out these questions much either.

In order to figure out what on Earth is going on, the Pierre Auger Observatory was built down in a remote corner of Argentina. The thing is huge: it covers an area the size of Rhode Island and consists of over a thousand detectors in an attempt to get a sizable amount of data. (One of these detectors is in the picture on the left.) They're collecting data as we speak, but in order to get a full scope of the sky there are plans underway to build a northern component to the observatory, which would be built in Colorado.

Anyway, the point of my project is to see if there's a cost-effective way of building a Cherenkov light detectors for the northern Auger. Cherenkov light this bluish radiation you see whenever something is moving faster than the speed of light in a medium- light doesn't travel as fast through air as it does through space, so if a high-velocity cosmic ray plows through the atmosphere faster than it should be going you see radiation as a result. This radiation can help you pinpoint how much energy your cosmic ray had in the first place, so if you could distribute weatherproof, cost-effective Cherenkov light detectors in the field would be really cool.

Two other seniors have had this as their project already which has proven to be both a good and a bad thing: good because a lot of the design is already taken care of (leaving me primarily with tying up loose ends, testing, and analysis), but the bad news is these past seniors did not leave much by way of documentation! Yeah, ends up there's a reason they're such sticklers about you keeping your lab notebook tidy... also, as the third person to have this project it's sort of on my shoulders to finally conclude if a detector of this nature is feasible, and I need to say something by November so no pressure or anything.

I will say though, I am excited about this: it's the sort of project that lets you get your hands dirty and actually accomplish something, which is unfortunately not something you'll hear about in all senior thesis projects. Plus the nature of cosmic rays is one of the biggest mysteries in astrophysics right now and it's very, very exciting to think that your work might help find an answer! Either way, saying you spent your summer working in a High-Energy Astrophysics laboratory sounds a lot cooler than saying you worked some anonymous internship, doesn't it?