1983 TeV 2011
September 30, 2011 10:35 AM   Subscribe

Wednesday night, my friend Todd showed me the key he had made. On the fob was engraved the following text. "1983 TeV 2011". Today, at 2PM CDT, Helen Edwards, the lead scientist of the machine in 1983, will turn that key, and the Tevatron will shut down forever.

The world's most powerful collider for over two decades, the Tevatron -- named after the energy goal, one trillion electron volts (TeV), was the first to observe the Top Quark. An enormously complicated machine, with 774 superconducting magnets, it was originally designed for fixed target work, but made most of its discoveries as a collider, slamming 36 bunches of protons into 36 bunches of antiprotons.

Along with the Tevatron, the two detectors, CDF, named as the Collider Detector at Fermilab, and D0, named after the location on the Tevatron ring, and three other accelerators, the Antiproton Source's two rings and the Antiproton Recycler will also shut down.

Fermilab itself will continue with the years of data reduction from the CDF and D0 experiments. Along with that, as Fermilab moves from the high energy to the high intensity realm, neutrino research continues with the MINOS, MiniBooNe, and upcoming NOvA experiments, and the lab as a whole will move into a new realm -- muons -- with the Muon g-2 and mu2e experiments leading to the next big experiment at Fermilab, Project X.

In the penultimate Tevatron accelerator update, several people who've worked with the machine reminisce about building, repairing, coddling, and trying to understand a machine that always ran on the edge of failure to push the boundaries of science.

The enormous R&D effort needed to build the Tevatron was critical in the design and construction of the machine that would finally exceed the luminosity and intensity of the Tevatron, the Large Hadron Collider. Fermilab was a fundamental part of building the LHC -- although not always without mistakes, but Fermilab's years of working with superconducting magnets was critical in building the much larger LHC, and one of the remote control centers of the LHC lives today at Wilson Hall, amongst the prairie and the bison that are as much a part of Fermilab as neutrinos, physicists, and temperamental machines.
posted by eriko (44 comments total) 20 users marked this as a favorite
Rest in peace, Tevatron. Sorry we didn't bother to finish your big brother, the SSC.
posted by wierdo at 10:37 AM on September 30, 2011 [3 favorites]

Ars Technica published an article a couple days ago about how the proposed Muon collider project might happen. With all the scientific and engineering knowledge there it seems almost a sin not to re-purpose it.

I visited Fermilab a few years ago and I was impressed with basically everything that goes on there. What was amazing was how they were able to speak to people from vastly differing educational backgrounds.
posted by thewumpusisdead at 10:47 AM on September 30, 2011

Wilson Hall is one of my favorite buildings. It looks exactly like you'd want the nerve center of a giant accelerator to look.
posted by COBRA! at 10:48 AM on September 30, 2011

Thanks, eriko!

For one insider's eulogy. . . Smash Hits:
The final collisions at Fermilab's Tevatron collider bring to an end an odyssey that began in Bob Wilson's (not the Arsenal goalkeeper's) mind as Elvis topped the charts with The Wonder of You; produced its first collisions to the accompaniment of Jennifer Rush warbling about The Power of Love; and discovered the top quark just as Celine Dion was advising the world to Think Twice.
posted by Mister Bijou at 10:51 AM on September 30, 2011 [1 favorite]

Fermi lab is a modern cathedral. They explore fundamental physics, but don't forget they also treat certain forms of throat cancer with neutrons, they work on restoring the prairie and raising bison. They're pretty much the best of our civilization.

(I wish particle physics weren't so dreadfully boring)
posted by Chekhovian at 10:52 AM on September 30, 2011 [5 favorites]

So... what you're saying is the Tevatron is not the machine they use to make Tevas. Shame.
posted by nathancaswell at 10:52 AM on September 30, 2011 [1 favorite]


The Chicago Reader ran a nice retrospective this week. I had no idea that Fermilab's location was inspired by a bit of small town boosterism gone awry:
...Weston village president Arthur Theriault had heard that the Atomic Energy Commission was looking for a home for its new particle accelerator...Theriault thought that the accelerator lab might bring the town the economic growth it'd been seeking—that a "science city" could form with the lab as its basis...

In December 1966 the Atomic Energy Commission chose Weston for the new lab. Weston had ample space for housing scientists, the University of Chicago and other colleges weren't far away, and the town was just a 30-minute drive from O'Hare. The science city wouldn't be Weston, though—it would swallow Weston. The AEC's plans had the lab displacing the town entirely, with the state using eminent domain to capture the land and transfer ownership to the lab.
posted by Iridic at 10:55 AM on September 30, 2011 [6 favorites]

My high school biology teacher used to take some of us dedicated nerds out to Fermilab where he worked part-time (yep, even back in the 60s/70s, teachers were paid like serfs), so as teens we got to see this remarkable edifice that eventually became home to the Tevatron. We got to meet Dr. Bob Wilson, director of the Fermilab & one of the original designers/proposers of the Tevatron & Dr. Lederman who eventually followed Wilson as director (and who was head of the team that "discovered" the Upsilon particle(Wiki).

Coolest thing I remember about Doc Wilson: the locals in nearby Warrenville & West Chicago were plagued with both brownouts & blown fuses from electrical spikes when the collider was pulling & returning electricity from the power lines. He designed & had built a device shaped like a huge tree (sort of) that had the job of being a surge protector. In the early days, people in the area feared Fermilab with a nuclear/cold-war fervor, but moves like that helped convince people that Fermi was a good neighbor.

Now that Tevatron's being decommissioned, it can be used for its backup purpose & churn out Teva sandals at breakneck speed. (with nod of head towards nathancaswell)
posted by beelzbubba at 10:59 AM on September 30, 2011 [2 favorites]

Regarding Weston, Illinois: only part of the Fermilab would displace what was once Weston, IL, a small village whose own board voted itself out of existence in order to provide Fermilab with a home. My guess is that the local boosters also had farmland to sell at a far better price than could be had on the open market at that time.
posted by beelzbubba at 11:04 AM on September 30, 2011

Someone needs to write a children's book of the same genus as Mike Mulligan And His Steam Shovel in which Helen Edwards and the anthropomorphized Tevatron show that upstart Large Hadron Collider what's what, one more time.
posted by Halloween Jack at 11:06 AM on September 30, 2011 [11 favorites]

I interviewed for a job as an accelerator operator at Fermilab two years ago. Got to sit in the seat in the control room, see the beam sources, and got one hell of a tour of the facility. It also didn't hurt that Femilab seemed a whole lot less.....stuffy than any of the other Physics labs that I've worked in.

Suffice it to say, I completely flubbed the interview, and did not get the job.

Although part of me is very glad that I'm not being put out of a job by the Tevatron shutdown, another part of me weeps that I'll never have that opportunity again.

Also: Fermilab will continue to exist. There are lots of other experiments going on there, and their Neutrino experiments are of obvious particular interest given the recent results out of CERN.
posted by schmod at 11:09 AM on September 30, 2011

...and the Tevatron will shut down forever.

What are the chances it could be booted back up periodically? There are only so many particle colliders around the world. Wouldn't there be a need for independent confirmation should the LHC discover the Higgs-Boson and/or rend a hole in the fabric of space-time, flooding the universe with soul-sucking ectocreatures?
posted by Terminal Verbosity at 11:13 AM on September 30, 2011

Checkhovian, bite your tongue. Particle physics? BORING? Comeon man, we're breaking fundamental symmetries over here.

I work at Fermilab, and can hear them setting up for the shutdown party as I type this. The shutdown and budget uncertainties have made this last year pretty interesting to be a scientist here, but I'm new here and I can't really talk to much about the lasting changes to lab. I think the biggest effect on morale (at least among theorists) is that we don't have a clear goal for a new collider coming down the pipeline. The other experiments are interesting and worth the effort, but nothing gets physicists going like a collider. From a science perspective, we can't do anything till the LHC tells us where to look next, but it takes 20 years to build one of these things, and as people retire (or are forced to retire), we lose a huge amount of institutional knowledge that will make a new collider that much harder and more expensive to build.

On a (somewhat) lighter note, the beam dump for the Tevatron keeps one of the ponds here ice-free all year. There was a lab-wide email sent out discussing the effects of the shutdown on the pond's duck population (one of the other beam dumps will be active, so they should be able to move one pond over).

I'll add a quote by Robert Wilson here, in response to a question by Congress on how Fermilab would contribute to national defense:

"It has only to do with the respect with which we regard one another, the dignity of men, our love of culture. It has to do with: Are we good painters, good sculptors, great poets? I mean all the things we really venerate in our country and are patriotic about. It has nothing to do directly with defending our country except to make it worth defending."

(but for the bottom-liners out there, I think that the contributions of Fermilab and American particle physics to the American scientific juggernaut still makes us an economic bargain and a net positive for national security.)
posted by physicsmatt at 11:15 AM on September 30, 2011 [20 favorites]

. He designed & had built a device shaped like a huge tree (sort of) that had the job of being a surge protector.

The capacitor tree. It wasn't so much a surge supressor as a power factor corrector. The Main Ring* presented a huge inductive load to ComEd**, which meant to handle it, the ring effectively drew far more power*** than it used. Since the load was inductive -- an inductor, after all, is simply a coil, and the Main Ring was a very big coil -- the solution to bring the current waveform in line with the voltage waveform was a large bank of capacitors, which would be tuned to the coil. The fact that they were in a tree is very Robert Wilson, who designed the original power poles at the lab to look like the letter π.

I have heard a story -- from Todd, actually -- about being stuck up there during a thunderstorm. Eep.

Nowadays, the tree isn't used -- faster automatic systems are used to switch in caps as needed, and lowering the entire inductance of the ring was a requirement of the Tevatron, given the individual inductance of the magnets (.6H)

* The predecessor to the Tevatron -- in the pics in the top link, the Main Ring Remnant, used to move beam to the fixed target areas from the Main Injector, is the blue machine on top, and is made of standard electromagnets and peaked at 400GeV, but with vastly lower current. The lower, red machine is the Tevatron.

** Huge, as in "measured in henries."

*** Here, we get into real power, measured in watts, apparent power, measured in volt-amperes, and reactive power, measured in reactive volt-amperes, or var. Power companies deliver in volt-amperes, but bill in watts, so when the power factor is bad, they have to delivery much more volt-amperes than they get to bill in watts. If your PF is consistently low, they charge you more for electricity. I asked Todd once, if the lab annoyed ComEd more than ComEd annoyed the lab, and he said "It's sort of a tie at times...."
posted by eriko at 11:18 AM on September 30, 2011

Godspeed, Tevatron!
posted by roboton666 at 11:19 AM on September 30, 2011

There's a decent PBS documentary about Fermilab from 2008, released by Independent Lens, called The Atom Smashers that I enjoyed watching a few months ago, if you want to see the internal workings and their budget struggles. Their website has links to a few places to watch it beside Netflix Instant, but that's where I saw it.
posted by skynxnex at 11:21 AM on September 30, 2011 [1 favorite]

Physicsmatt, I like the way Neil DeGrasse Tyson put it: The things done with an accelerator (or any other theoretical work for that matter) will not change anybody's life in the next 5 years. Instead, the discoveries made through hard science provide the fodder for inventors to use to revolutionize the world 20 years from now. It's no less useful than more immediate engineering work, it's just done on a longer horizon.

Unfortunately, we seem to be losing the collective will to look that far into the future.
posted by wierdo at 11:24 AM on September 30, 2011 [3 favorites]

in response to a question by Congress on how Fermilab would contribute to national defense

It's unbelievable how ignorant members of Congress can be.
posted by GuyZero at 11:24 AM on September 30, 2011 [2 favorites]

Terminal Verbosity; the magnets have to be kept cold, vacuums have to be maintained. It costs ~$100 million a year to run this thing (if I remember correctly), and I imagine a lot of that is spent up front getting the accelerator up and ready to go (so, running for 1 month is not 1/12th the cost of running for a year). Right now, we don't even have the budget to dismantle and mothball the experiment; we're just shutting it down.

However, we will have 10 inverse femtobarns of data* per experiment, and only ~7 have been analyzed. Certain things are easier to see at the Tevatron compared to at the LHC. For any collider, lots of strongly interacting events at "low" energy are produced (here low just means << beam energy), which are background to new physics that you might want to look for. Since the LHC is higher energy than the Tevatron, this annoying background is somewhat worse at higher energies (comparatively). So looking for certain types of events are easier at the Tevatron just because the background is lower. So, for example, right now, due to the range of Higgs masses that are still possible, the LHC will have to find the Higgs. However, once that's done, if it's in a certain range of masses, the Tevatron data can be used to look for other decay products of the Higgs (the LHC would find them eventually, but it would take more luminosity -- in order to reduce the statistical importance of background -- and that takes time). So we're still relevant.

*A barn is a unit of area: 1 bn = 10^-24 cm^2. The probability of interactions goes like the "cross section," measured in barns. Think of it as "surface area" of the objects being thrown at each other. Smaller cross sections are harder to create because they're harder to "hit." Higgs cross sections are 10's to 100's of femtobarn (1000 fb = 1 pb), so to tell how many events we expect, we multiple the cross section by the "Luminosity" (how many proton/antiprotons we collide), to make things easy, we measure luminosity in inverse femtobarns (or inverse picobarns), so a cross section of 10 fb with a luminosity of 10 fb^-1 would give 100 events. One of the oddities that messes up new grad students is that higher luminosity goes with SMALLER prefixes. 1 fb^-1 is 1000 times better than 1 pb^-1.
posted by physicsmatt at 11:27 AM on September 30, 2011 [5 favorites]

... and now off to the party. There will be cake.
posted by physicsmatt at 11:28 AM on September 30, 2011 [9 favorites]

Strange. That is exactly the same thing engraved on the key to my DeLorean.
posted by chemoboy at 11:34 AM on September 30, 2011

Looking at the accelerator status, store #9158 will be the final store in the Tevatron. Pbar is in access, so the antiproton rings there are already off. Old Habits Die Hard, of course, so despite the last store, they've got the Recycler chock full of pbars.

I imagine a lot of that is spent up front getting the accelerator up and ready to go (so, running for 1 month is not 1/12th the cost of running for a year).

Yes, which is why the lab did the rolling furloughs last year, rather than shutting down the accelerator complex for a month. Plus, in terms of science, not only do you lose the shutdown month, but you lose a good part of the next month as they try to get everything retuned and running smoothly.

I'm glad the last store is a good, clean one, initial luminosity between the two detectors was about 360x10e30 fb-1.

Someone else at the lab mentioned "thankfully, we made the MainIinjector a jack-of-all-trades." Even though it won't be feeding the TeV or PBar anymore, the NuMI and fixed target test work will keep it busy until new experiments are online.
posted by eriko at 11:34 AM on September 30, 2011

360x10e30 fb-1

Dammit. 360x10e30 cm-2s-1, or 360 μb-1s-1. It's not integrated yet. I swear I knew that...
posted by eriko at 11:41 AM on September 30, 2011

I kinda hope that for the last half hour or so, y'all are just dumping change and shit in there to see what you can collide.

"I think we have a chance at finding new paperclip and jerky particles!"
posted by klangklangston at 11:59 AM on September 30, 2011 [2 favorites]

There will be cake.

Did a disembodied robotic female voice tell you that? If so, BE CAREFUL!
posted by kmz at 12:08 PM on September 30, 2011 [1 favorite]

From the shutdown event: of course the kill switch is a big red button. I appreciate their design philosophy.
posted by physicsmatt at 12:15 PM on September 30, 2011 [2 favorites]

CDF just shutdown. Unlike the TeV, they used a mouse. :-/
posted by eriko at 12:23 PM on September 30, 2011

CDF is off. They, along with D0, found the top quark.
posted by physicsmatt at 12:24 PM on September 30, 2011


Enjoy the cake, physicsmatt, and watch out for handsy experimentalists.
posted by Diagonalize at 12:29 PM on September 30, 2011

D0 now offline.
posted by eriko at 12:32 PM on September 30, 2011

And there goes D0. It's up to ATLAS and CMS now.
posted by physicsmatt at 12:33 PM on September 30, 2011

CDF and DO HV now offline, ready for end of store.
posted by eriko at 12:34 PM on September 30, 2011

TeV aborted.
posted by eriko at 12:36 PM on September 30, 2011

TeV offline. Run IIA over.

Nice work, everyone. Never forget you did great things.
posted by eriko at 12:36 PM on September 30, 2011 [1 favorite]

It's just something in my eye....
30 Sep 2011 14:41:25
The TeVatron is now off.
posted by eriko at 12:43 PM on September 30, 2011 [2 favorites]

A barn is a unit of area: 1 bn = 10^-24 cm^2.
There was an barn-related askme the other day.
posted by zamboni at 1:00 PM on September 30, 2011

For a half-second there, physicsmatt, I thought you were a friend of mine who worked on MINOS and NOVA and who's also named Matt.

I hope funding stays in place for all the Matts and non-Matts in US physics research. It's cool to know more.
posted by jiawen at 1:25 PM on September 30, 2011

Checkhovian, bite your tongue. Particle physics? BORING? Comeon man, we're breaking fundamental symmetries over here.
I work at Fermilab

I'm sure glad there are people that find high energy interesting so that I don't have to do it. I do find it weird that physics is always "math, data, math, data", not stamp collecting. Then you learn the standard model as our penultimate insight into the universe. and it pretty much seems like stamp collecting.
posted by Chekhovian at 2:13 PM on September 30, 2011

Chekhovian, sorry, didn't mean to be actually mean in my response there. Still a bit confused though, since particle physics is about as far from stamp collecting as you can get. It's reductive rather than descriptive: the goal is to reduce the laws of nature down as far as they go, not memorize lists of things (which is what stamp collecting in science usually is interpreted as). Probably not a necessary derail though.

And to update, the cake was not a lie.
posted by physicsmatt at 3:36 PM on September 30, 2011 [1 favorite]

the goal is to reduce the laws of nature down as far as they go, not memorize lists of things
I shouldn't disrespect you brave high energy guys so directly. I've just never been able to sit through high energy talks without immediately entering snooze mode e.g. "here are all these leptons, here are all these quarks, etc etc".

You would agree with me though that the standard model doesn't really "feel" like the base level physics right? The limited amount I've been able to absorb feels like we just have this list of stuff and no insight beyond that. Admittedly that stuff has withstood every experimental test to man's highest levels of precision, but there's just gotta be something more.
posted by Chekhovian at 3:59 PM on September 30, 2011

Or even worse, Medium Energy physics...the most boring of energies.
posted by Chekhovian at 3:59 PM on September 30, 2011

Oh, of course the Standard Model isn't the basis of physics. It's just as far as we have gotten so far. String theory tried to jump way ahead and get to the bottom of everything, but I think it has overreached itself and has turned into a math exercise which doesn't connect very much with experiment. Right now, I'm just trying to plod along and move just a bit further than the Standard Model (also, completing it with the Higgs would be a nice first step).

The amazing thing about particle physics (and what elevates it above stamp collecting) is how intricately the Standard Model fits together: yes there are more moving parts than one might want, but it's like a building where every beam rests against the others. The more you study it, the more clear it becomes that it's really hard to build such a theory. That's also one of the things that convinces me that there has to be deeper underlying physics.

Anyway, my original response was mostly in jest, and I certainly have no hard feelings towards people who aren't as monomaniacal as me and my colleagues. It takes all kinds, and if everyone did this, I'd have to deal with more competition.

(though medium energy physicists are the ones making all the useful stuff)
posted by physicsmatt at 5:17 PM on September 30, 2011 [2 favorites]

posted by lester at 7:57 PM on October 1, 2011

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