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Why LHC use proton-proton collide instead of proton-antiproton(like,Tevatron) collide?
What is the advantages use proton-antiproton than proton-proton collision?more difficult; producing antiprotons and having high luminoisty with them.
Yes, all of that is true but you left out the most important advantage of the proton-antiproton colliders. That is the ease of identification and detection of some of the most interesting events. If there are any vector particles to be discovered in the mass range of 2 to 12 TeV, the proton anti-proton collider can produce a clean signal of a particle decaying near at rest, while the proton-proton collider produces the same signal along with 100 tons of other garbage that you have to sort through very very carefully. On one hand the higher luminosity helps with the proton-proton colliders, on the other, the signal to noise ratio at the detectors hurts you. Overall, you win for some processes (probably most I must admit), but you lose for others. Worst of all, for a few select (but important) processes you lose extremely badly (by more than an order of magnitude.)you only need one magnet ring, instead of two since the antiproton has opposite charge.
for some processes, the reaction rate is higher for p-bar + p than p+p, but only at "low" energies such as 1-3TeV (which is energy for the Tevatron), but for higher energies, such as 10 (LHC range), this advantage dissapears.
So the advantages is that you only need one set up of magnet rings, and that at lower E, reaction rate is higher for some processes.
Disadvantages is that producing and facilate antiprotons is very diffcult, and that the higher reaction rate is reduced when increasing the energy.
Are you sure that you mean proton-antiproton and not electron-positron? This is usually given as an argument in favor of e+e-.If there are any vector particles to be discovered in the mass range of 2 to 12 TeV, the proton anti-proton collider can produce a clean signal of a particle decaying near at rest, while the proton-proton collider produces the same signal along with 100 tons of other garbage that you have to sort through very very carefully.
I disagree with "no reason whatsoever". For very heavy new physics - say a Z' at 10 or 12 TeV - one does better with pbar-p. However, for the vast majority of things we want to study, like you say, there is no physics advantage and a luminosity penalty to go to pbar-p. So it's not difficult to see why this particular design choice was made.However, for the LHC, there is no reason whatsoever to make antiprotons - you don't gain anything (gluon pdfs are the same in both p and pbar), and you loose out from the complications (both in luminosity and cash!) of making antiprotons.