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Particle beam has What Amount of voltage per meter LHC

  1. Jul 4, 2015 #1
    So for sake of example the LHC beam one pointing at the other to cause a collision, the one beam is 6.5 TeV per beam. How can I calculate the volts per meter or given size of pulse? I understand that the particles have kinetic energy in the form of the speed of their travel but theoretically isn't it possible that if you had a positive beam and a negative beam that you could point the beams to a fantastically large cathode and anode of a light bulb and it would light it up as long as the particle beam was continuing to provide a flow of positively charged particles and circuit of negative charge particles. Or at the least you could bleed off that energy with a magnet. Isn't it true that some magnetic force is occurring when the LHC is turned off and the particles are continuing to move past the magnets or it would be true for a short period in a straight accelerator beam, no?

    I would like to compare/contrast a charged particle beam to a bolt of lightening to explain to students.
    An average bolt of negative lightning carries an electric current of (1)30,000 amperes (30 kA), and transfers (2)15 coulombs of electric charge and (3) 500 megajoules of energy. Duration of 30 microseconds. Wikipedia.

    So a 30 microsecond pulse of the LHC would have an electric current of (1) ? amperes and transfer (2) ? coulombs of electric charge and have (3) ? amount of megajoules of energy.

    I guess a related question is whether the LHC beam is a charged particle beam which is a spatially localized group of electrically charged particles that have approximately the same position, kinetic energy (resulting in the same velocity), and direction.

    Thank you in advanced.
     
  2. jcsd
  3. Jul 5, 2015 #2

    mfb

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    6.5 TeV per proton in the beam. There are about 1011 protons per bunch, and up to ~2500 bunches per beam (achieved so far: ~1300). They make about 11000 revolutions per second. You can multiply those numbers with the 1 elementary charge per proton to get total charge, beam current and stored energy.

    Volts per meter is not a meaningful unit for the beams.

    Both beams consist of protons with a positive charge.

    Which magnetic force where? When the LHC turns off, the beams get disposed of within a millisecond. Ramping down the magnets afterwards needs about 20 minutes.

    That is a good approximation for the individual bunches, but particles at one side of the ring clearly have a different position and direction than particles at the other side.
     
  4. Jul 5, 2015 #3
    If the beam has positive charged particles then it should have some measurable charge. So I don't know how to precisely communicate the questions but basically I'm asking if you put an induction coil next to the beam how much current would be generated in just one revolution or one pass of the 1,300 bunches consisting of 10 to the 11th power protons in each bunch? Assuming a reasonably sized coil with a reasonable size amount of windings.
    So something like:
    (1.602176565(35)×10−19 coulombs )x(10 to the 11th power x 1,300) = amount of volts?
    You use Faraday's law of induction to determine the amount of current that can be generated. Conceptually, you are doing the reverse of what the LHC does. It uses electricity to create a proton beam. Conversely, you should be able to take a proton beam and convert it to electricity, no?
     
  5. Jul 6, 2015 #4

    mfb

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    Sure. Roughly 50 microCoulomb at design parameters.
    That depends on much more - the precise geometry, the distance to the beam, the resistance of the coil, its inductivity and so on.
    Sure, but then you slow down the protons in the LHC, and the conversion is very inefficient.
     
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