The Benefits of the Cancelled SSC in Texas

[CookieSalesman]

The SSC that was planned to be built in Texas was cancelled, and was supposed to produce protons of about 20 TeV?

Can anyone tell me exactly why it would have been much better?
For instance, discovering the higgs-englert would have been easier, and sooner, had we used the SSC- but what other experiements require such energies? What's the benefit of the SSC? Apparently we can't test string theory with the SSC...

 

[RGevo]

It terms of centre of mass energies:
The hard interaction for producing new particles can be well described by the interaction of partons (quarks /antiquarks and gluons) within the hadron and the associated probability of finding these partons with a given energy with the hadron.

If the colliding hadrons have more energy, this means kinematically the partons can have higher energy, but perhaps more importantly is the probability of finding a Parton in both hadrons with enough energy to produce a particle X (the Higgs for example) can increase dramatically.

A good example is the gluon-gluon luminosity for producing a 125 GeV object. Here is and old plot with some luminosities
http://lutece.fnal.gov/PartonLum/WebFigs/gglum.pdf

On the other hand, the detectors which were designed back then would not have been as good (older technology). So less precision in the measurements (with more statistics).

On string theory, current collider experiments are not directly testing string theory. If string theories are designed in a way to have phenomenological consequences (such as heavy Gauge bosons), then these things may be tested at current collider searches (http://inspirehep.net/record/265862/citations, I just googled this last one as an example)

 

[mfb]

The SSC was planned with a lower collision rate (only 10% of the LHC design luminosity) - for low-energetic particles the LHC is better. At the Higgs mass, the higher luminosity would probably win, and the SSC would have needed a bit longer to find it (but it would have started earlier...).

In addition to the higher parton probabilities RGevo mentioned, a higher energy simply allows to look for heavier particles. We don't know if there are particles with 15 TeV, for example, but the SSC would have had some chance to proce them, while it is completely impossible to directly produce them at the LHC. Indirect searches still allow to look for them, however.