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Science

Tevatron Beams Turn On At FermiLab 39

Posted by timothy from the and-earth-is-still-here dept.
skwang writes: "This press release at Fermi National Accerator Labratory (FermiLab) announces the start of "Collider Run II." FermiLab collides protons and anti-protons in order to study high-energy phyisics (HEP). One of the labs goals is to find the Higgs Boson, an elementary particle that couples with mass. More information about Run II Physics can be found at the FermiLab Web site or at the detector Web Sites: D-Zero (D0) and Collider Detector at FermiLab(CDF)"
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Tevatron Beams Turn On At FermiLab More

Tevatron Beams Turn On At FermiLab

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  • Bad Link (Score:1)

    by Anonymous Coward
    the first link to the fermilab is www.gnal.gov, it should be www.fnal.gov
  • You can find it at http://www.bnl.gov/bnlweb/pubaf/pr/bnlpr020801.htm It's called the g-2 experiment at Brookhaven National Lab.
  • Well, it was muon precession measurements, and although it got a lot of press I'd hardly say a 2.7 sigma deviation rules anything out. I wouldn't be surprised if improved calculations and more data made this go away, just like all of the other false alarms in recent years.
  • No, but I am curious as to what Burt Reynolds and Dom DeLuise's involvement might be. Do you think Jackie Chan will have a cameo?
  • I can send you a topo if you want it. :)

    --SONET
  • My last AutoCAD drawing was of the particle accelerator at Fermi for the National Department of Energy. What a bitch that was. The funny part was, they sent me cut up hard-copy drawings to go from along with what they wanted added on hand-drawn on the work (placement for a ton of fiber!); the majority of my work was piecing together what they already had (which had been drawn in AutoCAD before - and they still had the AutoCAD files). It is policy for them to do it this way so people don't pass top-secret information in the drawing files. In a way I can see what they are thinking, but in another way... what a huge waste of money. I charged them quite a bit to re-create something they already had.

    Anyway, those plans were such a pain that they brought me to quitting AutoCAD completely. Even though they paid me quite well, it just wasn't worth the hassle. heh

    --SONET

  • Paris: Captain, the Borg are trying to pull us in with a tractor beam!

    Janeway: Direct a Tevatron pulse through the deflector grid, that should disable their tractor beams.

  • Mr. Freeman, so good to see you today... You're wanted in the Tevatron laboratory right away!
  • I've got a few friends that work over at Fermi, they've been cutting back the work force to increase spending on their colliders. In fact they are working on one right now that will send a proton through the earth and collide in Minneapolis. Can't wait to see the results of that.

    ----------------------------------
  • Don't laugh. My employer received a loaner server (E3500) from Sun that had done a stint at Fermi. They had to pass components of the system through radiation testing several times before they'd allow it to leave the premesis to come to us. Oddly enough, they didn't wipe its drives first. Oh well.
  • They have over 2000 nodes running Linux including desktops and farm workers, with plans to buy 100s more this year. One of the coolest things is seeing Linux being used right next to the Origin 2ks and Sun boxes...


    --------
  • Yeah, I'd be inclined to agree for the most part...
  • If, indeed, the "clobbering" refers to the g-2 muon anomaly experiment recently completed by Brookhaven, then it has no effect on the relevance of Run II. In fact, if you read the press release and other information on the Fermi Lab website, you'll realize that both experiments have similar purposes: to probe physics beyond the Standard Model, such as supersymmetry. These additional elements enrich the Standard Model, definitely not clobbering it.
  • Yeah, but you seem to be a Debian user, and /. readers prefer Mandrake this week, so don't expect to be modded up, or anything like that!

    FP.

    (if I have to say '+1 funny not -1 troll', then it probably wasn't funny, was it? Ooops)
    --
  • Mother of god, a trillion electron volts [auger.org] thru a pair of sport sandals? That can't be good for my feet!

    While I'm sure it kicks the ass of the tree-hugging Birkatron [birkenstock.com], I have to believe that something like the Nikatron [nike.com] will eventually replace it due to reduced, off-shore labour costs.
  • To split some more hairs, actually Newton's gravitational theory is more properly defined as an approximation of a more general theory (General Theory of Relativity), just as Newton's Laws of Motion are the zero-velocity limits of Special Relativity.
  • Let's hope they don't blow a hole in the Bozon layer ...

    Dave
  • funkbrain is misleading when he says Newton's theory is "incorrect". The test of a theory is the extent to which its predictions match experimental data. Newton's theory is not incorrect, rather it is not as accurate as the theory of General Relativity. Indeed, it is usually impossible to prove that a theory is 100% correct since it is impossible to test the infinite number of conditions it predicts. If Newton's theory of gravitation is "incorrect", why do engineers, astronomers, astro-physicists use it every day? Newton works well except in very special circumstances, in these cases GR is more accurate.
  • For instance, what research is going on to build the world's first handheld railgun? If the U.S. Army gets hold of that weapon, they can recruit all the Quake players in the nation and send a hail of depleted uranium slugs flying toward the enemy!

    Then again, an army of hundreds of thousands of railcampers is never good.

  • Expect the next Katz article to be "Bosons in the Workplace"...
  • This posting by funkbrain should definitely be moderated up.

    Thanks,
    Fred Gray

  • I find this rather hard to believe: absolutely no classified research is done at Fermilab.

    On the other hand, this might be the result of a generic DoE policy that no one has taken the time to review for appropriateness to the facility.

  • Well, using it is one thing, but our group's experience with Linux wasn't anything better than our experience with Windows. It was just different problems to get around. Hardware compatibility was also huge issue since we were doing processor and graphics intensive simulations, and we were unable to buy the best equipment. The decision to use Linux was made not because of it's features, but because the price was right.
  • Believe it or not, the first railgun was developed during World War 2! It was designed to act as an anti-aircraft weapon that couldn't be spotted by muzzle flashes (and thus attacked from the air).

    Unfortunately the muzzle velocity never reached what the military concidered a pratical level, but imagine if it had! Railguns used in World War II? What a concept!
  • Well, the Higgs Boson is the last item in the Standard Model, and finding it would complete the Standard model. Unfortunately, recent boson precession measurements show the Standard Model is wrong. Oh well, it's still kinda nice to explain mass. Even in a dead model!
  • >Unfortunately, recent boson precession measurements show the Standard Model is wrong. Oh well, it's still kinda nice
    >to explain mass. Even in a dead model!

    I don't believe this is "unfortunate" and it certainly isn't a bad thing for Fermilab. In addition to looking for the Higgs, there will be searches for new physics (i.e. physics beyond the standard model) in Fermilab run 2 data, just as in run 1. SUSY (supersymmetric) Higgs possibilities will be examined as well as the standard model Higgs. And in general, most physicists have thought that the standard model was inadequate, hence all of the theoretical work on SUSY, superstring theory, additional extended spatial dimensions, and other ways of going beyond the standard model.

    You said "boson precession measurements." I assume you're alluding to the muon g-2 experiment? I believe they claim 99% confidence for a value that does not match the standard model. While that is compelling, it's just not enough sigmas to be decisive.

    A couple of other notes... I'm just an undergrad, so people with more experience in physics can feel free to correct me:

    Don't expect to see an announcement of the Higgs discovery right away. It will take time to collect enough data for a "discovery," although I suppose Higgs-like events could show up relatively soon. Also, I think the Higgs is harder to detect in p-pbar collisions than in e+ e- collisions (as at LEP) because the decay modes leading to the Higgs are closer to some background processes. But perhaps someone who knows more about this could explain.

    And last, a technical note for all the Slashdotters who think every article should relate to Linux. Most of the work being done at Fermilab is on Linux, specifically Fermilab Linux, which is based on RedHat. For the CDF experiment, the Run 1 code was written in Fortran, but most Run 2 code is in C++. There are a number of modules which process event data, and TCL scripts are used to set module parameters and the order in which modules are run. ROOT is used to interactively run C++ scripts for data analysis based on the output of these modules. I don't know much about how D0 operates but I believe it's similar.
  • Run II is actually divided into 2 parts, a and b with a shutdown for upgrades between the two parts. The entire run is supposed to last 3 (or 5?) years and have an integrated luminosity of 10 fb-1. Each experiment (D0 and CDF) is expected to take somewhere between 1 and a few petabytes of data (yes, that's PB = 1000 TB = 1000000 GB plus or minus 1000 vesus 1024 or so). It is expected that this dataset will contains 1000's of top quark events and a few 100 Higgs events (assuming that the Higgs mass is low and in the Tevatron energy range).
  • The proposal for the detector said that it would have a luminosity of 2 fb-1 (inverse femto-barns for those who don't know the units) but the techs at Fermilabs have a reputation of getting better then predicted luminosity. It is probably too early to tell, but does someone know if they have once again done better then expected? Talking with my advisor 2 fb-1 isn't good enough to get reliable information on the existance of the Higgs, and considering I am doing some research in Supersymmetry I am very interested the potential discovery of a "low" energy higgs.

  • "Mrs. Tweedy, Mrs. Tweedy! I tell ya, those particles, they're organized!"

    Did this go through anybody else's head when the read "Collider Run II"?
  • Sorry but you got most of the facts wrong :(

    See this link for the real story on this... http://www.hep.anl.gov/ndk/hypertext/numi.html [anl.gov]

  • It's true... I'll post a link if I can find it. The group of physicists were using a relatively new measurement technique, which is supposed to be more accurate. They divided the data-gathering work into two independent parts, and gave each part to a different group of scientists, to keep the results from being colored by wishful thinking. When the datasets were related and analyzed, the results disputed the standard model. There's a 10% chance that their data is incorrect, but the implications are deep enough that the experiment will likely be repeated. If the results are verified, this is big news.

    (Although, since AFAIK GNU/Linux wasn't used by the scientists, it's not big enough news for Slashdot, I guess.)

    --

  • For a minute there, I read "Bossoms in the Workplace", and I thought it had something to do with Sexual Harrassment in the workplace. Or working at a topless bar.

  • Here's the text of the article, since it seems to be borderline /.'ed:

    Batavia, Ill-Officials at the Department of Energy's Fermi National Accelerator Laboratory today (March 1) announced the start of Collider Run II at the Tevatron, the highest-energy particle accelerator now operating in the world. Researchers at Fermilab hope that high-energy particle collisions at the Tevatron in Run II will yield significant, long-awaited discoveries about the fundamental nature of matter in the universe.

    Fermilab Director Michael Witherell expressed satisfaction at the culmination of the laboratory's decade-long preparations for Run II and anticipation of the scientific opportunities it will provide.

    "I am delighted that we are starting Run II on time," Witherell said. "Now we can look forward to the excitement of seeing new physics results. We can't predict what Nature has in store for us. All we can guarantee is the opportunity for discovery."

    Like Witherell, many Fermilab scientists stressed that, while they have models and theories, they do not know what new physics Run II will reveal. Nevertheless, world attention has focused on Fermilab's two collider detectors at the Tevatron, CDF and DZero, as the next possible venue for discovery of the Higgs boson, an as-yet-unseen particle that physicists believe may determine the property of mass. Late last year, experiments at the Large Electron Positron collider at CERN, the European Laboratory for Particle Physics, detected hints of what might have been signals of the Higgs. However, the LEP accelerator shut down before scientists there could either confirm or rule out a Higgs sighting. If the Higgs boson does exist at a low enough mass, Fermilab experiments may be able to detect it during Run II.

    Run II also has the potential for revealing much more new physics, including evidence for a theoretical model known as supersymmetry, signals of possible extra dimensions in the universe, new insight into the asymmetry between matter and antimatter and a better understanding of the top quark, discovered at Fermilab in 1995 during Collider Run I. All are subjects with profound implications for modern particle physics and for the understanding of the fundamental physical workings of the universe.

    "Two recent results from other experiments add to the excitement of Run II," said Fermilab theorist Joseph Lykken. "The results from Brookhaven's g-minus-two experiments with muons have a straightforward interpretation as signs of supersymmetry. The increasingly interesting results from BABAR at the Stanford Linear Accelerator Center add to the importance of B physics in Run II, and also suggest new physics. I will be shocked and disappointed if we don't have at least one major discovery."

    During Run II, beams of protons at an energy of 980 billion electron volts will collide with beams of antiprotons at the same energy, for a total energy of 1.96 trillion electron volts at the collision point, a 10 percent increase over the energy of Run I. However, the greatest enhancement of the Tevatron's capability will come from the use of a new injection accelerator, the $260 million Main Injector, completed in 1999. The Main Injector and other improvements will permit a much greater rate of high-energy collisions in the Tevatron, providing more than a 20-fold increase in the number of particle collisions observed and recorded at the particle detectors. Because the new phenomena that physicists are seeking occur extremely rarely in particle collisions, the increased collision rate is critical to making discoveries.

    Although Collider Run II officially began on March 1, it will take some weeks before Fermilab physicists begin seeing physics results from the upgraded and newly configured Tevatron.

    "Turning on the Tevatron is not like turning on a toaster," said Fermilab Operations Chief Robert Mau, whose department operates Fermilab's accelerators. "Besides the approximately seven miles of particle beam enclosures, the accelerator complex includes 44,000 controllable devices and more than a hundred thousand readbacks. Millions of components, circuits and parts all have to work together. The Tevatron is one of the most complex devices on earth. It takes a while to get it up and running."

    Mau expects to see proton beams in the Tevatron within a few days. Experiment collaborations at the CDF and DZero detectors should begin observing proton-antiproton collisions later in March. The collaborations, each comprising about 550 physicists from universities and laboratories throughout the nation and the world, have each completed five-year, $100-million upgrades to take advantage of the Tevatron's enhanced capabilities.

    "Our sensitivity to new physics comes not only from the big increase in numbers of collisions," said CDF collaborator Rob Roser. "We gain an additional factor due to beam energy and a further increase due to the improvements in our detector. For top-quark physics, for example, we are looking at about a 50-fold improvement over Run I."

    Run II will continue, with a mid-course interruption for further upgrades and improvements to accelerators and detectors, until 2007. At about that time, results will begin to emerge from a new accelerator, the Large Hadron Collider at CERN, which will have seven times the Tevatron's energy and will overtake the Tevatron at the high-energy frontier. Fermilab scientists are eager to make the most of the opportunities now before them.

    Experimenter Robin Erbacher expressed the prevailing sentiment among physicists at the laboratory after five years of work and preparation for Run II.

    "I'm ready to get my hands on some data and analyze it," Erbacher said.

    Fermilab is operated by Universities Research Association, Inc., under contract with the U.S. Department of Energy, whose Office of Science funds more than 90 percent of the federally supported research in high-energy physics in the United States.

  • There's a comment in the main post about the Higgs "coupling with mass". The Higgs Boson doesn't couple to mass, rather, it gives a mass to fermions through a coupling of the form HYY, where H is the Higgs and Y are fermions. When the Higgs has a non-zero expectation value this effectively looks like the fermions have a mass term. Also, it's not quite right to say that the measurements of the muon anomalous magnetic moment are out of line with Standard Model predictions. I'd love it if these experiments are in fact showing us indicators of physics beyond the Standard Model, but there are a lot of factors that go into calculating g-2, any one of which might explain the recently observed value.

  • Linux at FermiLab (Score:3)

    by elerium ( 21148 ) on Saturday March 03, 2001 @02:36PM (#386993)
    Just because I remember stumbling across it some time ago and bookmarking it, and because it's fun to advocate Linux positively by showing that real people are choosing (and pleased) to use Linux for real things:

    Linux at Fermi National Accelerator Laboratory [fnal.gov]

  • tevatron? (Score:3)

    by martyb ( 196687 ) on Saturday March 03, 2001 @01:28PM (#386994)

    Tevatron? How did they get electronics into my sandles? ;) Gives new meaning to going for a power walk, too!

    (cf http://www.Teva.com [teva.com])

  • You seem to have some serious misunderstandings about this...

    First things first, he experiment to which you refer is the g-2 experiment at Brookhaven [http] ; it is an experiment to measure the anomolous magnetic moment of the muon (which is a fermion, not a boson).

    The anomolous magnetic moment of the muon is a physical quantity predicted by the SM (a prediction which is itself a paramaterization of other measured quantities, and thus has some uncertanty). The g-2 experiment yielded a value which is 2.5 standard deviations away from the SM prediction.

    This is a good thing for physicists (specifically the ones at Fermilab)! For one thing, no serious physicist has ever believed that the standard model is a complete description of nature. There are aspects of the universe for which the standard model cannot account (for example the obvious matter-antimatter asymmetry...).

    The really exciting thing about the g-2 result and it's potential impact on the physics about to happen at Fermilab is that it is highly suggestive of new physics (i.e. supersymmetry... susy).

    Think of the progress of scientific thought in the past 600 years. Newton's gravitation is a good theory; it makes predictions which mach quite well with observation (experiment). However, it is incorrect... along came Einstien's theory of gravitation, (General Relativity, which itself is a good theory, but not the correct one) which reproduces all of the predictions of Newtonian gravity, and and "does one better" by getting right what Newton got wrong (i.e. precession of the orbit of Mercury; the deflection of light by massive objects...).

    So we have the standard model, which is by far the most successful physical model in human history. Yet we know it's wrong. But untill we find a better description of nature, it'll have to do.

    The standard model is far from dead. It will evolve, in some sense, into a better description of nature.

  • Hi, folks,

    I'm a graduate student who works on the experiment to which this thread is alluding. It is the muon g-2 experiment [bnl.gov].

    The post to which I am responding contains several factual errors:

    • There is about a 1 or 2 percent (rather than 10 percent) probability of obtaining this result by chance if the "true" value is given by the Standard Model. In any event, this is a probability of obtaining the result because of a statistical fluctuation, rather than a mistake (as implied by the phrase "their data is incorrect).
    • We actually use GNU/Linux for the vast majority of our data analysis! Our data acquisition system, which moves the raw data from the electronics to DLT tapes, is based on vxWorks. Essentially every other step in the analysis chain runs on Linux machines, either at Brookhaven or one of the collaboration institutions. For instance, we have a cluster with twelve dual 500 MHz Linux machines in our group here at the University of Illinois.
    • In some sense, the experiment has already been repeated. The result that we recently announced was based on an analysis of only about 20 percent of the data that we currently have on tape. We're working hard on getting the rest of it analyzed, though: hopefully we'll have an answer by the end of the year. Then I can write my thesis, add "Ph.D." to my name, and start collecting the kind of salary that IT people make straight out of high school. :-)

    Thanks,
    Fred Gray

  • Aha! (Score:5)

    by jjeffries ( 17675 ) on Saturday March 03, 2001 @03:02PM (#386997)
    I guess this explains the splattered whale carcass and smashed flower and pot in my front yard...

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