This Friday, Fermilab will turn off the Tevatron for the last time after a 28-year run. It has been a constant in my life as a particle physicist, and indeed for a whole generation of particle physicists. I know some people who have managed to spend their entire careers involved with the Tevatron in some way. Not true for me; I was on hiatus at the Cornell Electron Storage Ring for five years as a graduate student. But the Tevatron was where I had my first experiences as an undergraduate researcher; as a college freshman, I was stunned to find myself with a Fermilab ID card in my pocket and suddenly in on the hunt for the top quark. (No dice; another six years, significant detector upgrades, and more than an order of magnitude more data had to come first.) And as a postdoctoral researcher, it was where I had my greatest triumphs (moderate as they may be) as a full-time researcher. (As a professor with many other things to juggle, it would be a stretch to call me a full-time researcher now.) I learned a tremendous amount along the way about physics and about how to be a physicist.
(But I will not be attending the shutdown ceremonies on September 30 — it’s Rosh Hashanah, the Jewish new year. What is it with the managers of particle physics laboratories who can’t read a calendar? So much for getting Fermilab Today to pick up this blog post….)
The Tevatron’s longevity surely puts it into a special category of scientific enterprises that have captured the public imagination because of their epic scope. The Voyager 1 satellite, for instance, has been chugging along since 1979, and barring unforeseen circumstances will continue to tell us about the nature of the universe. The Tevatron in its own way will keep chugging along too, as there is so much data yet to analyze that it will keep teaching us about the universe for some years to come.
I’m not going to tick off all of the accomplishments of the Tevatron and CDF and D0, its principal experiments; this has been done elsewhere, and also has been covered in excellent presentations at the DPF meeting by Steve Holmes and Paul Grannis, both of whom were there pretty much from the beginning. (Chris Quigg also provides a lovely summary of the physics achievements in the CERN Courier.) But what I would like to point out is that the Tevatron program of 2011 is not the program that was envisioned when the machine design was launched in the late 1970′s. The clear targets of the machine were the W and Z bosons and the top quark, and these are now understood in detail because of the Tevatron. But as far as I know, no one anticipated the program of bottom-quark physics that emerged, no one thought that precision measurements of masses could be done at a hadron collider, and even just a few years ago it would have been optimistic to suggest that the Tevatron experiments would have the capability to observe the Higgs boson. On the accelerator side, the final instantaneous luminosity was a factor of 400 better than design, meaning that there was an average 35% annual improvement over twenty years.
Since this is an LHC blog — what can we learn about the LHC from this? It is that we should not underestimate the potential that we have in front of us. The LHC will likely operate for as long as the Tevatron has, and we can realistically expect similar performance improvements along the way. We should also not underestimate how our experimental reach can be increased through advances in detector technology, and the just plain cleverness that physicists will bring to the table when given the chance to solve a challenging and important problem. In 2037, there will be new generation of particle physicists for whom the LHC is a constant of life, and I expect that we will be looking back on an LHC legacy that is just as memorable as that of the Tevatron.