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New Particle Collider Is One Foot Long

Jason Koebler writes The CERN particle collider is 17 miles long. China just announced a supercollider that is supposed to be roughly 49 miles long. The United States' new particle collider is just under 12 inches long. What the SLAC National Accelerator Laboratory's new collider lacks in size, it makes up for by using plasma to accelerate particles more than 500 times faster than traditional methods. In a recent test published in Nature, Michael Litos and his team were able to accelerate bunches of electrons to near the speed of light within the tiny chamber."

17 of 161 comments (clear)

  1. so size DOESN'T matter? by Anonymous Coward · · Score: 5, Funny

    i'm so confused.

    1. Re:so size DOESN'T matter? by Anonymous Coward · · Score: 4, Funny

      No, only how hard you thrust particles.

    2. Re:so size DOESN'T matter? by Anonymous Coward · · Score: 5, Funny

      The Republicans took control of the Senate just yesterday, and we are already seeing results. American capitalism and Yankee ingenuity has beaten those big government and high tax liberal Europeans. This would have never happened if Harry Reid was still in charge.

    3. Re:so size DOESN'T matter? by DoofusOfDeath · · Score: 4, Funny

      Obama to SLAC's creators: "You didn't build that."

    4. Re:so size DOESN'T matter? by Anonymous Coward · · Score: 5, Funny

      George W. made some huge contributions to particle physics during his presidency:

      President Bush met with members of the Fermi National Accelerator Laboratory research team Monday to discuss a mathematical error he recently discovered in the famed laboratory's "Improved Determination Of Tau Lepton Paths From Inclusive Semileptonic B-Meson Decays" report.

      Bush shows Fermilab scientists where they went wrong in their calculations.

      "I'm somewhat out of my depth here," said Bush, a longtime Fermilab follower who describes himself as "something of an armchair physicist." "But it seems to me that, when reducing the perturbative uncertainty in the determination of Vub from semileptonic Beta decays, one must calculate the rate of Beta events with a standard dilepton invariant mass at a subleading order in the hybrid expansion. The Fermilab folks' error, as I see it, was omitting that easily overlooked mathematical transformation and, therefore, acquiring incorrectly re-summed logarithmic corrections for the b-quark mass. Obviously, such a miscalculation will result in a precision of less than 25 percent in predicting the resulting path of the tau lepton once the value for any given decaying tau neutrino is determined."

      The Bush correction makes it possible for scientists to further study the tau lepton, a subatomic particle formed by the collision of a tau neutrino and an atomic nucleus.

      Bush resisted criticizing the Fermilab scientists responsible for the error, saying it was "actually quite small" and that "anyone could have made the mistake."

      "High-energy physics is a complex and demanding field, and even top scientists drop a decimal point or two every now and then," Bush said. "Also, I might hasten to add that what I pointed out was more a correction of method than of mathematics. Experimental results on the Tevatron accelerator would have exposed the error in time, anyway."

      Fermilab director Michael Witherell said the president was being too modest "by an order of magnitude."

      "In addition to gently reminding us that even the best minds in the country are occasionally fallible, President Bush has saved his nation a few million dollars," Witherell said. "We would have made four or five runs on the particle accelerator with faulty data before figuring out what was wrong. But, thanks to Mr. Bush, we're back on track."

      "It's true, I dabbled in the higher maths during my Yale days," said Bush, who spent three semesters as an assistant to Drs. Kasha and Slaughter at Yale's renowned Sloane High-Energy Physics Lab. "But I didn't have the true gift for what Gauss called 'the musical language in which is spoken the very universe.' If I have any gift at all, it's my instinct for process and order."

      Continued Bush: "As much as I enjoyed studying physics at Yale, by my junior year it became apparent that I could far better serve humanity through a career in statecraft."

      While he says he is "flattered and honored" by the tau-neutrino research team's request that he review all subsequent Fermilab publications on lepton-path determination, Bush graciously declined the "signal honor."

      "This sort of thing is best left to the likes of [Thomas] Becher and [Matthias] Neubert, not a dilettante such as myself," Bush said. "I just happened to have some time on the plane coming back from the European G8 summit, decided to catch up on some reading, and spotted one rather small logarithmic branching-ratio misstep in an otherwise flawless piece of scientific scholarship. Anyone could have done the same."

    5. Re:so size DOESN'T matter? by ClickOnThis · · Score: 5, Informative

      It would have been good form to cite your source.

      --
      If it weren't for deadlines, nothing would be late.
  2. Not exactly by Anonymous Coward · · Score: 5, Informative

    If you read the article (damn you, paywall!) you note that this is essentially an afterburner, and does not start with stationary electrons. In this particular instance it requires a 2 km linear accelerator before the 12 inch magic booster box. 20 GeV electrons are accelerated by a further 1.6 GeV. Still interesting research, but definitely not what is claimed in the summary (surprise).

    1. Re:Not exactly by joe_frisch · · Score: 4, Informative

      If you do a Google search on

      SLAC PUB plasma wakefield
      you will find a lot of non-paywalled papers on this and related plasma accelerator experiments at SLAC.

    2. Re:Not exactly by Chalnoth · · Score: 4, Informative

      There's no problem in daisy chaining them, but I don't think you can guarantee the same energy boost each time. One of the big physics problems here is that accelerating charged particles radiate when they are accelerated, which acts as a sort of friction. The amount that is radiated increases quite dramatically as the particle gets closer to the speed of light (the energy loss scales as (E/(mc^2))^4). In practice, this means that if you dump a bunch of energy into an electron to accelerate it, you'll only add a fraction of that amount to its kinetic energy (the rest will be lost in radiation).

      Given this, the naive expectation is that each subsequent box will add less and less to the energy of the particles. The disclaimer here is that I haven't studied the specific physics of plasma shock acceleration, so I don't know how such acceleration scales with energy. I do know, however, that this is the exact same mechanism that is suspected to be behind the "oh my god" particles (single particles with more than ten million times the energy that the LHC can produce): plasma shock fronts in the galaxy accelerate some small fraction of the interstellar protons to unbelievable speeds.

    3. Re:Not exactly by the+gnat · · Score: 4, Informative

      Yes, that is actually before the US entered WWII and long before the invention of the cyclotron.

      Huh? The cyclotron was invented in 1932. Obviously a relatively primitive instrument (it would easily fit on my kitchen table), but the underlying design is still in use.

  3. It's been done...in 1959 by 602 · · Score: 5, Interesting

    Here's a tabletop particle accelerator in Scientific American's Amateur Scientist column in 1959: http://www.sciencemadness.org/... And in the Sept 1953 issue, an account of some high school students in El Cerrito who built a cyclotron.

  4. Not a collider by AchilleTalon · · Score: 4, Informative

    Actually, it is the accelaration module that is 1 foot long. It is not a collider, it is an accelerator a collider would be at least two feet long and in reality would have more than one acceleration module.

    --
    Achille Talon
    Hop!
  5. SLAC FACET accelerator by joe_frisch · · Score: 5, Informative

    I am peripherally involved in the SLAC plasma wakefield accelerator described in the article.

    It provides a very high energy gain in a short distance, but needs to be driven by a high energy drive beam. The present design uses a 20GeV drive beam (using part of the old high energy physics accelerator).The required drive beam energy could be reduced to ~10GeV but probably not a whole lot lower. So this is a way to build a relatively short very high energy accelerator, but not a way to build a very short low-medium energy machine.

    Other labs are working on laser driven plasma accelerators that do not need to start with a high energy beam, but do need an enormous laser system and are presently limited to much lower average beam powers .

    Plasmas are very promising for future accelerators and there was some excellent work done at SLAC as well as laser / plasma accelerators at other labs. There is still a lot to do. There are issues with staging multiple plasma cells to get high energies, beam quality and stability issues etc.

    1. Re:SLAC FACET accelerator by joe_frisch · · Score: 4, Informative

      That is a slightly different concept. This uses a medium-energy (20GeV), high current electron beam to drive the plasma, which then accelerates a high energy beam.

      There is also a scheme to use a high energy proton beam to drive the plasma, and a scheme to use a high power (Peta-watt) laser to drive the plasma.

      All are being seriously considered / developed by various laboratories.

      This type of scheme probably doesn't apply well to a circular machine like LHC because the energy limit there is the magnets used to bend the beam into a ring .You might accelerate the protons at the end, but you wouldn't be able to send them back for re-use and you would not get enough collisions to get interesting physics.

  6. Re:Compensating, again by budgenator · · Score: 5, Funny

    It may only be 12 inches long, but it's 1.5 MeV around!

    --
    Apocalypse Cancelled, Sorry, No Ticket Refunds
  7. USA are a country? by CaptQuark · · Score: 4, Informative

    The Unites States of America are a country

    A group is considered a single entity if all the members of the group are addressed together. You cannot have a group of "United States" be a country without including all 50 of them so they are addressed as a single group. The capitalization of United States of America also indicates you are referring to the collection of all 50 states together.

    In contrast, if you said "The Red States are more conservative." then you are referring to the individual states in that group so they are treated as a plural subject.

    Other examples: The Pit Crew is efficient, but the pit crew members are tired. The choir is rehearsing, but the choir singers are upset. http://public.wsu.edu/~brians/...

    ~~

    1. Re:USA are a country? by Richard_at_work · · Score: 4, Informative

      It depends on where you come from - its natural here in the UK to use "are" for the collection, eg "Microsoft are..." rather than "Microsoft is..."