Neutrino Mass Verified

April 2, 2006

From 1999 to 2001, as an undergraduate research assistant, full-time employee, and then graduate research assistant, I worked on a high energy physics project called MINOS. Just this week the project finally announced its first results: neutrinos do indeed have mass. And this has made me a bit nostalgic, even though in most respects I was miserable at the time.

This is the project overview I wrote for my MA thesis in physics while in the High Energy Physics Lab at The University of Texas at Austin:

While the standard model of particle physics does not require neutrinos to trade flavors—or oscillate—many physicists believe that they interchange just as other leptons and quarks do.  Further, oscillation theory demands that, in order for oscillations to take place, neutrinos must have a positive, non-zero rest mass.  The original use of neutrinos to explain beta decay required them to have no mass whatsoever.  Thus if these particles are massive at all, it is only in the sense of having mass, but not much of it.

Recent experiments such as Super Kamiokande in Japan and those at the Sudbury Neutrino Observatory have offered strong evidence for neutrino oscillations.  One problem with these experiments is that their neutrinos are either solar or atmospheric, and thus there is no certainty about the original composition of their source particles. The MINOS project on the other hand will aim a high intensity beam of neutrinos, originating at Fermi National Accelerator Laboratory in Batavia, IL., at a detector in a remote mine in Soudan, Minnesota.  By comparing the statistical contents of the controlled beamline at Fermi with that 735 km away in northern Minnesota, the project’s collaborators hope to more firmly establish evidence of oscillations and produce more accurate boundaries for neutrino mass.

Keeping it brief, my role was to write software used to analyze the characteristics and quality of photo detectors. Doing so afforded me little opportunity for any real physics, which was one part of my misery. On the other hand, I enjoyed the programming work (which has led to a great job), and I really wasn't very good at physics anyway. I was also rather despondent and depressed for non-school reasons, with school and personal life feeding off each other. Another factor was the number of hours required to excel and the number of hours I wanted to dedicate to the Baha'i community of Austin and to the United Religions Initiative.

At least once a year for the past five I've become nostalgic for the research I was working on. Mind you I'm not necessarily wishing to be back doing the exact things I was doing... I think it is more of a nostalgia for what could have been, for what I once felt so sure I wanted (to be a research physicist). And that is an incredibly important realization.

What could have been was never meant to be, at least in the way I imagined it. Just when I think I've fully come to grips with that, something stirs up this old mental wound. The reality, I think, is that I was too attached to a specific idea, compounded by the naïvety to think I could excel at the very subject that, even in the introductory classes, I found the most challenging.