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Protons Collide At 13 TeV For the First Time At the LHC
An anonymous reader writes to let everyone know the LHC has now smashed protons together at 13 TeV, the highest energy level yet achieved. They've posted the first images captured from the collisions, and explained the testing process as well. Jorg Wenninger of the LHC Operations team says, "When we start to bring the beams into collision at a new energy, they often miss each other. The beams are tiny – only about 20 microns in diameter at 6.5 TeV; more than 10 times smaller than at 450 GeV. So we have to scan around – adjusting the orbit of each beam until collision rates provided by the experiments tell us that they are colliding properly." Spokesperson Tiziano Camporesi adds, "The collisions at 13 TeV will allow us to further test all improvements that have been made to the trigger and reconstruction systems, and check the synchronisation of all the components of our detector."
well this was actually a calibration not a "test". From my understanding to make sure no stray particles are going "off track" they ran this test. So while it is the first time its been run to full power, it wasnt for any reason other than calibration. Now, I dont know if they are collecting and running any data on the collisions that did happen
have you seen my sig? there are many others like it but none that are the same
The true excellence in the LHC is not its maximum collision energy alone (which of course is awesome in itself), but the luminosity and resolution that is included with it. The reactions that are hunted occur at miniscule rates, and the major effect of the LHC is the big step up in several orders of magnitude as the pure number of collisions go. The design figures quoted for the SSC luminosity were only an order of magnitude lower than corresponding figures for the LHC, but that is not to be taken lightly.
Regarding energy resolution, the SSC would probably due to its time have been comparable to Tevatron, which is a factor 5 worse than the LHC. In practice this accounts to a large disadvantage for particle detection, which could qualitatively be mulitplied by the difference in luminosity, leaving the SSC at a disadvantage of about a factor 50 in resolving new particles, though compensated to some degree by its higher maximum energy. In a way, this might mean that it would have been more difficult to discover the Higgs with SSC, but that it would had greater potential in finding physics "beyond the standard model". The latter statement is extremely speculative, though, since the LHC has not even been running near its maximum capacity yet.
Also, the intended much larger jump in maximum energies as compared to available technology at the time might very well have led to SSC becoming a giant money-eating hole, which is one of the very reasons it got cancelled. It would be easy (for a certain definition of "easy") to draw up blueprints for a machine 10 times more powerful than the LHC -- but you would need to be a right-out magician to make it realizable due to monetary constraints. The LHC was successful in this regard, much since it could draw on the lowered price of technology over time as compared to SSC, which is another fantastic achievement by the design team. The re-use of the tunnels saved an enormous amount of construction funding, which could instead be channeled towards more interesting technology advancements.
Projects such as the SSC, Clic, ILC, etc., are greatly useful in their own right, even though they might not end up in realizable machines. The ideas and experiences from the design phase permeate to upcoming projects. As an example, the "Super" in SSC meant the use of superconducting magnets, which is a basis of the LHC construction.
The lack of computing resources at the time would also have been a major blocker for SSC, as you mention. In the design of the SSC, it in hindsight seems like they designed it without real regard for the needed monetary investments, or at least as if they expected several orders of magnitude larger funds than reasonably were to be expected. Perhaps the design process started in a different climate, and they expected "blue skies" scientific budgets to continue to rise so that they would meet their requirements when the design phase was done, when the actual development turned out to be the opposite.