Why was the LHC required to find the Higgs?

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SUMMARY

The Large Hadron Collider (LHC) was essential for discovering the Higgs boson due to its higher luminosity and advanced detector technology compared to the Tevatron. While the Tevatron could achieve 1 TeV collisions and had previously identified the top quark, it lacked the necessary sensitivity to detect the Higgs at 126 GeV with the required 5 sigma significance. The LHC's proton-proton collisions, characterized by a larger gluon Parton distribution function and a significantly higher cross-section, resulted in approximately 50 times more Higgs particles detected, despite only 2.5 times more background noise.

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  • Understanding of particle physics and the Standard Model
  • Familiarity with collider physics, specifically proton-proton collisions
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  • Basic concepts of cross-section and Parton distribution functions
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  • Research the differences between LHC and Tevatron collider technologies
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Particle physicists, researchers in high-energy physics, and students studying the Higgs boson and collider experiments will benefit from this discussion.

copernicus1
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If the Higgs is around 126 GeV, why was the LHC required to find it, when the Tevatron is capable of 1 TeV collisions and had already found the top quark which is quite a bit heavier? Is this because of something special about proton-proton collisions?

Thanks!

PS Please don't say "they did see the Higgs at the Tevatron!" I'm aware of those results, but clearly there must've been some reason why the LHC was thought to be more effective in discovering this particle.
 
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It is more difficult to see the Higgs particle in the noise. Identifying the top quark is easier than identifying the Higgs. So you need a collider with higher luminosity, which is the LHC.

Regarding the Higgs being "found" at the Tevatron: I don't think they had 5 sigma significance to declare a discovery.
 
Also, at the LHC the production is dominated by gluon fusion process via top loop.

With higher energy hadrons (3.5, 4 TeV) the gluon Parton distribution function is larger and thus the cross section increases.

Also Lhc detectors are newer technology, so in general better
 
http://pdg3.lbl.gov/atlasblog/wp-content/uploads/2010/04/Picture-1.png
The plot is older than the discovery, so there is no line for 126 GeV, but 150 GeV is close enough. At the LHC, the cross-section is more than an order of magnitude larger (even with 7 and 8 TeV), and at the same time the LHC collected more collisions (25/fb integrated luminosity, while the Tevatron experiments got 10/fb). This means the LHC experiments had ~50 times more Higgs particles, with just ~2.5 times more background.
And the LHC detectors are better, of course.

Antiproton-proton collisions would have been even better, but at the LHC energy, that does not matter so much any more.
 
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