If Higgs has mass of 125GeV why did the LHC need 3.5TeV?

[SheriffPeabody]

Hi, I've tried to find an answer to this question, sorry if it's already been asked. I'm sure I have misunderstood something important here, but if the Higgs was found to have a mass of 125GeV, why did we need such a powerful collider to find it? (I think the LHC was running at 3.5TeV when they found the Higgs particle)

I'm guessing there's more to it than just power, but I'm wondering why it wasn't possible to have found the Higgs at a different lower powered collider?

 

[Orodruin]

The 3.5 TeV was the energy of the protons being collided. The partons inside the proton (quarks and gluons) only carry a fraction of this energy. At 3.5 TeV, you would need to get very lucky to find a parton collision where the partons each carry a large part of the energy. It is much more likely to have a collision where the partons carry only a fraction of the total energy.

 

[SheriffPeabody]

Ah right so it's technically possible to find it at lower energy collisions, but just incredibly unlikely?

 

[mfb]

It is technically possible to produce it at lower energy, just incredibly unlikely. Finding it is even more challenging, because most collisions produce other particles and you have to find the few events with Higgs in them. I wrote an insights article about this.
A higher energy increases the fraction of collisions with a Higgs.

 

[Vanadium 50]

It's a question of practicality. The Teavtron would have found the Higgs in the 2 photon mode (which is not the best mode for them) had they run long enough. However, "long enough" is 1600 years.