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Europe's LHC To Run At Half-Energy Through 2011 194

Posted by samzenpus
from the part-time-collision dept.
quaith writes "ScienceInsider reports that Europe's Large Hadron Collider will run at half its maximum energy through 2011 and likely not at all in 2012. The previous plan was to ramp it up to 70% of maximum energy this year. Under the new plan, the LHC will run at 7 trillion electron-volts through 2011. The LHC would then shut down for a year so workers could replace all of its 10,000 interconnects with redesigned ones allowing the LHC to run at its full 14 TeV capacity in 2013. The change raises hopes at the LHC's lower-energy rival, the Tevatron Collider at Fermi National Accelerator Laboratory in Batavia, Illinois, of being extended through 2012 instead of being shut down next year. Fermilab researchers are hoping that their machine might collect enough data to beat the LHC to the discovery of the Higgs boson, a particle key to how physicists explain the origin of mass."
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Europe's LHC To Run At Half-Energy Through 2011

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  • Re:Damn... (Score:1, Informative)

    by Anonymous Coward on Wednesday February 03, 2010 @11:13PM (#31018464)

    7 TeV is about 1 microjoule, which is the energy that a 400 Watt computer would use in 3 nanoseconds.

  • by Maury Markowitz (452832) on Wednesday February 03, 2010 @11:25PM (#31018548) Homepage

    > much higher collision rate than the Tevatron

    About 100 times. But remember that cross section goes down with E, so the effective collision rate at high energies is just about flat. See:

    http://lhc.web.cern.ch/lhc/general/acphys.htm

    TRIUMF still kicks in this regard.

    Maury

  • Re:Damn... (Score:5, Informative)

    by marcansoft (727665) <hector@marcans o f t . com> on Thursday February 04, 2010 @12:14AM (#31018784) Homepage

    The beam energy at 7TeV is 362 megajoules. This is about the energy that you could get by maxing out a household mains connection (230V 20A) for one day, or about the energy content of 11 liters of gasoline. Quite a bit, but not huge at energy scales.

    Of course, the beauty of the LHC is that it accomplishes this energy in the form of a particle beam circling the collider at near the speed of light. This means that the power of the beam is about 4 terawatts if my math is right, so it could power about 3300 DeLorean time machines (not for very long, though). Keep in mind that this power is circling endlessly in the LHC, so it isn't being consumed - the actual electric power consumption to run the whole LHC is "only" about 120 megawatts.

  • by Idarubicin (579475) <allsquiet@hotma3.14il.com minus pi> on Thursday February 04, 2010 @12:16AM (#31018794) Journal

    I seem to have heard this argument before.
    The Apollo fire. The loss of the Challenger. Repairs to the Hubble.

    I seem to have heard this misconception before. The Apollo fire wasn't because of a cutting-edge project taking technical risks, or making a considered judgement to accept smaller safety margins in exchange for reduced costs.

    Having a mixed-gas oxygen-nitrogen atmosphere in the Apollo capsule would have increased the internal capsule pressure in orbit, requiring a beefier structure and more weight. More dangerously, it would have required the development of suitable partial-pressure sensors for the precise measurement of oxygen levels within a mixed-gas environment. That would have constituted a technical risk. In contrast, the system used in the original Apollo design required only a simple pressure gauge to ensure sufficient oxygen for the crew.

    Moreover, in orbit the Apollo capsule internal pressure would be only about 5 psi - about a third of an atmosphere. While that pressure of oxygen is sufficient to support combustion, it isn't dangerously high, and all of the materials used aboard Apollo were tested for fire safety under those conditions. The big problem was that on the launch pad, the capsule contained a full atmosphere of oxygen (the excess pressure would be bled off as the capsule ascended to orbit). Nobody thought to test under those conditions. Even then, there's at least some evidence to suggest that it was the astronauts' webbing the capsule with large amounts of Velcro that allowed the fire to spread so rapidly.

    Finally, the earliest design for the Apollo capsule hatch opened outwards and was equipped with explosive bolts for rapid egress. It was at the insistence of astronaut Gus Grissom (who may have been the victim of premature triggering of such a system on his Mercury capsule) that the hatch be replaced with an inward-opening, 'plug' design that lacked explosive bolts.

    Both previous manned U.S. space capsules (Mercury and Gemini) had used essentially identical pure oxygen atmospheres, without concern and without any problems. Did they get lucky? Absolutely, in retrospect. Should the Apollo engineers have recognized the dangers that their predecessors had overlooked? Probably. Was the fire the result of taking 'technical risks' on a 'cutting edge project'? Nope. They thought they were sticking with a simple system that had worked for years, and didn't want to asphyxiate an astronaut by fiddling with something reliable.

  • Re:Baguette (Score:2, Informative)

    by bdwlangm (1436151) on Thursday February 04, 2010 @12:21AM (#31018830)
    IIRC, the bird dropped its bread on something a little more innocuous [web.cern.ch] sounding than a reactor. The bird escaped unharmed but lost its bread.
  • by The_Wilschon (782534) on Thursday February 04, 2010 @01:22AM (#31019138) Homepage
    Cross sections for most interesting processes go up with a large power of E (~6) at a hadron collider. This is largely due to the gluon parton distribution functions: as you go to higher proton energies, you need smaller and smaller fractions of the proton energy for heavy particle production, and at small fractions of the proton energy, there are gillions of gluons. This has the additional interesting effect that heavy particles are primarily produced at rest, because the less of the proton's energy you use (and therefore less kinetic energy for the produced heavy particle), the more gluons are available to contribute to the cross section.
  • by Werthless5 (1116649) on Thursday February 04, 2010 @04:30AM (#31019900)

    Because the two machines operate at different collision energies. The Higgs cross section is going to be different at each collider due to this energy difference, so when you go to measure this cross section you're going to get different results.

    You can perform a meta-analysis, whereby you make a "best measurement" at different colliders and energies in order to better understand the measurements. However, that's not what you're proposing; you're proposing that they combine data in order to get a result in the first place, which you can't do.

  • Re:Half-measures (Score:3, Informative)

    by qmaqdk (522323) on Thursday February 04, 2010 @04:37AM (#31019940)

    Maybe you get a Schrodinger's black hole - it may or may not be there until you open the lid.

    No, no, no. It's both there AND not there until you open the lid.

  • by physburn (1095481) on Thursday February 04, 2010 @04:42AM (#31019954) Homepage Journal
    I very much doubt that the LHC will find the Higgs in its 2011, 7TeV is plenty of power to find a Higgs between 100 and 200 GeV, however the luminosity of the LHC and the number of collisions it will make is a lot lower too. The LHC will only deliver about 1 inverse femtobarns in that time. But the Tevatron has will a built up to 8.5 inverse femtobarns of collisions in that time. That means that the first years run of the LHC will be a drop in the ocean of the already existing Higgs data from the Tevatron. So hard luck Europe, but the LHC won't detect a Higgs before 2013. The Tevatron might just see the beginnings of a signal, but probably not enough to confirm anything.

    ---

    LHC [feeddistiller.com] Feed @ Feed Distiller [feeddistiller.com]

  • by zmooc (33175) <zmooc@z[ ]c.net ['moo' in gap]> on Thursday February 04, 2010 @06:25AM (#31020378) Homepage

    Oh there's so much more. The sinking of Columbus' ship Santa María comes to mind, the death of Marie Curie by cancer, the risks Franklin took when proving lightning was electricity and the murder of William Bullock by his printing-machine. Here are some more: http://listverse.com/2008/12/14/10-inventors-killed-by-their-inventions/ [listverse.com]

    The thing is, the greatest discoveries very often come at a great risk. The risk-averse culture than has steadily been introduced since, say, the 1970s probably greatly holds back mankinds progress. No longer are victims of cutting-edge technologic failures hero's, instead their designers are the victim of outrage and lawsuits. This makes me very sad. Risks are not something bad, risks are things taken by brave people. Very often those people are the ones responsible for great leaps in mankinds progress.

    Therefore the argument you quote is not just a good argument, it is a great argument. Wimps that cannot handle it should stay away from it and keep their mouth shut.

  • Re:Damn... (Score:3, Informative)

    by marcansoft (727665) <hector@marcans o f t . com> on Thursday February 04, 2010 @12:03PM (#31023136) Homepage

    Yup, synchrotron radiation. This is significant with electron accelerators, but the LHC accelerates heavy ions where it isn't that much of a problem. The synchrotron power emitted is about 3.7kW in total.

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