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Facts about the LHC and its future
Here's an article from The New Scientist about the LHC and beyond. It answers questions like "what are they looking for", and "what's next". It's interesting to read that they are already thinking about the next bigger hardron collider which might be available by the end of the next decade, after spending tons of money on the project. Will this device help invent new stuff that we might use in our day to day life ? We already have the microwave, what's next !?!
Who wants a black hole for diner ?
Here goes the article:
The Large Hadron Collider is by no means the last of the particle smashers. A group at CERN recently explored the various scenarios that might emerge from the atomic debris in Geneva – and how they would shape what colliders we build next. We draw out the key points about each of the scenarios.
Detect a Higgs
What will detecting a Higgs boson mean?
If the characteristics of the Higgs fit with the predictions of the standard model of particle physics, it should be found within three years. The discovery would confirm that a Higgs "field" permeates the universe, lending all other particles their mass. If it is a Higgs that does not conform to the standard model, it may turn up even earlier, because it would likely be lighter and so more commonly produced in collisions than heavier particles.
What next?
The Super LHC will have more collisions per second and be more accurate than the LHC, and would be able to start to explore the properties of a Higgs. Its high energy would be especially useful if the Higgs turns out to be heavy, though a linear collider would be more precise. The Compact Linear Collider would have an advantage over the International Linear Collider with its higher collision energy.
No Higgs
What will failing to detect a Higgs mean?
If no Higgs is detected after three years of the LHC running at full energy, then this points to a more complicated Higgs field. It could be because the Higgs decays to known particles that are difficult to detect at the LHC or it decays to invisible particles - ones that don't interact with the detector.
Failure could also be a sign of a non-standard model Higgs - which would mean it could be lighter or heavier than expected and thus harder to find. Or it could indicate a more exotic Higgs field - perhaps with several different Higgs bosons interacting in a way not yet fully understood.
What next?
Other mechanisms for endowing particles with mass will be seriously considered. For example, when two W bosons collide, they are thought to produce a Higgs. If no Higgs exists, however, whatever else is produced by W boson scattering would be the obvious next place to look for what endows matter with mass. The process could be examined extensively with the Super LHC.
No detection at the LHC could be bad news for the International Linear Collider, because it has a lower energy than the LHC and so couldn't look for a potentially heavy Higgs. The Compact Linear Collider would be the better option.
Supersymmetry
What will evidence of supersymmetry mean?
Supersymmetry (SUSY) is a theory positing that all the known particles in the standard model have partners. Unlike a Higgs, the particles would not show themselves directly. In some models, the particles pass through the detector without interacting with it. Their presence in a collision can be inferred from the imbalance of the total momentum - or in other words, the energy missing from the collision. In the most likely version of SUSY, the lightest particles should show up via this approach within the first year at the LHC. The lightest SUSY particle is a possible candidate for dark matter.
What next?
The Super LHC could start measuring the mass and spin of most SUSY particles and could detect unexpectedly heavy particles out of reach of the LHC. However, to study SUSY in detail, a linear collider would be far superior, because the initial energy of the colliding electrons and positrons is exactly known. At the LHC and the sLHC, the energy of the quarks and gluons inside the colliding protons is not known so it is harder to keep track of the overall energy and momentum. What's more, most models predict that the SUSY particles are below 0.5 teraelectronvolts, which makes the ILC the ideal machine to explore these particles.
New physics
What are the implications of new physics?
New physics refers to anything that lies beyond the standard model. Aside from supersymmetry (see above), this includes gravitons or particles associated with extra dimensions. If light enough, these could be seen fairly early on at the LHC. Likewise a next generation of the standard model could be discovered or excluded. More exotic suggestions include "unparticles", an entirely unrecognisable type of matter that could be detected by missing collision energy.
What next?
Once a new phenomenon is found, it will be necessary to flesh out the underlying theory. For example, supersymmetry or models with extra dimensions are the first steps towards confirming string theory. The Super LHC would collect vastly more data on any new physics than the LHC, and could discover processes too rare to be detected by its predecessor. Eventually, a linear collider will be necessary to complete the job - the best of the two proposed linear colliders would depend on the energy of the new phenomenon discovered.
The next generation
The Super LHC
The sLHC would be a souped-up LHC. If all goes to plan, it will come online in around a decade after upgrades. The beams would be 10 times as bright, which would involve increasing the number of protons in each beam by a factor of 10, and result in 10 times as many collisions per hour. This means the sLHC has a greater chance of seeing an interesting collision but also has more uninteresting collisions to filter through, as well as more radiation for the detector to withstand. To cope with these challenges, the beam injectors will be replaced, additional superconducting magnets will control the brighter beams, and detectors will be upgraded to cope with the higher data rates and radiation doses.
Date of completion: 2018
Cost: $1.27 billion
Pros: Much cheaper than building a new machine
Cons: Challenging environment to make precision measurements; only small increase in particle masses probed
The International Linear Collider
If the project receives financial backing after technical reports due in 2012, the ILC would be a 35-kilometre-long straight accelerator. While the LHC collides protons, which contain quarks and gluons, the ILC will smash electrons and positrons. Collisions will be "cleaner" than the LHC because electrons and positrons are fundamental particles. This makes for less ambiguity when trying to work out what produced any new particles. In the LHC, charged particles lose energy with each rotation.
Date of completion: 2020s
Cost: $8 billion
Pros: Cleaner collisions. Technology reliable and well understood
Cons: In some scenarios, the maximum energy may not be sufficient to see all new physics of interest
The Compact Linear Collider
The CLIC would be a positron and electron linear accelerator like the ILC - and is also yet to be approved - but it would be shorter and have collisions at higher energies. A high-intensity, low-energy drive beam runs parallel to the colliding beams. Power built up in the drive beam is transferred in quick bursts to the main beams.
Date of completion: 2020s
Cost: No official estimate, ~$10 billion
Pros: Cleaner collisions. High energy and compact - the ILC would need to be 140 kilometres long to achieve the same energy, so vastly more expensive. Greater sensitivity to massive particles compared with sLHC
Cons: R&D for the new technology is still at an early stage
Far in the future
Other proposals include the Very Large Hadron Collider, which would have a collision energy of 40 to 200 TeV and would have to be built from scratch. Muon colliders, and an LHeC - smashing an electron beam into a proton beam - are also being considered.
http://www.newscientist.com/article/mg20427354.900-future-colliders-beyond-the-lhc.html
Here's an article from The New Scientist about the LHC and beyond. It answers questions like "what are they looking for", and "what's next". It's interesting to read that they are already thinking about the next bigger hardron collider which might be available by the end of the next decade, after spending tons of money on the project. Will this device help invent new stuff that we might use in our day to day life ? We already have the microwave, what's next !?!
Who wants a black hole for diner ?
Here goes the article:
The Large Hadron Collider is by no means the last of the particle smashers. A group at CERN recently explored the various scenarios that might emerge from the atomic debris in Geneva – and how they would shape what colliders we build next. We draw out the key points about each of the scenarios.
Detect a Higgs
What will detecting a Higgs boson mean?
If the characteristics of the Higgs fit with the predictions of the standard model of particle physics, it should be found within three years. The discovery would confirm that a Higgs "field" permeates the universe, lending all other particles their mass. If it is a Higgs that does not conform to the standard model, it may turn up even earlier, because it would likely be lighter and so more commonly produced in collisions than heavier particles.
What next?
The Super LHC will have more collisions per second and be more accurate than the LHC, and would be able to start to explore the properties of a Higgs. Its high energy would be especially useful if the Higgs turns out to be heavy, though a linear collider would be more precise. The Compact Linear Collider would have an advantage over the International Linear Collider with its higher collision energy.
No Higgs
What will failing to detect a Higgs mean?
If no Higgs is detected after three years of the LHC running at full energy, then this points to a more complicated Higgs field. It could be because the Higgs decays to known particles that are difficult to detect at the LHC or it decays to invisible particles - ones that don't interact with the detector.
Failure could also be a sign of a non-standard model Higgs - which would mean it could be lighter or heavier than expected and thus harder to find. Or it could indicate a more exotic Higgs field - perhaps with several different Higgs bosons interacting in a way not yet fully understood.
What next?
Other mechanisms for endowing particles with mass will be seriously considered. For example, when two W bosons collide, they are thought to produce a Higgs. If no Higgs exists, however, whatever else is produced by W boson scattering would be the obvious next place to look for what endows matter with mass. The process could be examined extensively with the Super LHC.
No detection at the LHC could be bad news for the International Linear Collider, because it has a lower energy than the LHC and so couldn't look for a potentially heavy Higgs. The Compact Linear Collider would be the better option.
Supersymmetry
What will evidence of supersymmetry mean?
Supersymmetry (SUSY) is a theory positing that all the known particles in the standard model have partners. Unlike a Higgs, the particles would not show themselves directly. In some models, the particles pass through the detector without interacting with it. Their presence in a collision can be inferred from the imbalance of the total momentum - or in other words, the energy missing from the collision. In the most likely version of SUSY, the lightest particles should show up via this approach within the first year at the LHC. The lightest SUSY particle is a possible candidate for dark matter.
What next?
The Super LHC could start measuring the mass and spin of most SUSY particles and could detect unexpectedly heavy particles out of reach of the LHC. However, to study SUSY in detail, a linear collider would be far superior, because the initial energy of the colliding electrons and positrons is exactly known. At the LHC and the sLHC, the energy of the quarks and gluons inside the colliding protons is not known so it is harder to keep track of the overall energy and momentum. What's more, most models predict that the SUSY particles are below 0.5 teraelectronvolts, which makes the ILC the ideal machine to explore these particles.
New physics
What are the implications of new physics?
New physics refers to anything that lies beyond the standard model. Aside from supersymmetry (see above), this includes gravitons or particles associated with extra dimensions. If light enough, these could be seen fairly early on at the LHC. Likewise a next generation of the standard model could be discovered or excluded. More exotic suggestions include "unparticles", an entirely unrecognisable type of matter that could be detected by missing collision energy.
What next?
Once a new phenomenon is found, it will be necessary to flesh out the underlying theory. For example, supersymmetry or models with extra dimensions are the first steps towards confirming string theory. The Super LHC would collect vastly more data on any new physics than the LHC, and could discover processes too rare to be detected by its predecessor. Eventually, a linear collider will be necessary to complete the job - the best of the two proposed linear colliders would depend on the energy of the new phenomenon discovered.
The next generation
The Super LHC
The sLHC would be a souped-up LHC. If all goes to plan, it will come online in around a decade after upgrades. The beams would be 10 times as bright, which would involve increasing the number of protons in each beam by a factor of 10, and result in 10 times as many collisions per hour. This means the sLHC has a greater chance of seeing an interesting collision but also has more uninteresting collisions to filter through, as well as more radiation for the detector to withstand. To cope with these challenges, the beam injectors will be replaced, additional superconducting magnets will control the brighter beams, and detectors will be upgraded to cope with the higher data rates and radiation doses.
Date of completion: 2018
Cost: $1.27 billion
Pros: Much cheaper than building a new machine
Cons: Challenging environment to make precision measurements; only small increase in particle masses probed
The International Linear Collider
If the project receives financial backing after technical reports due in 2012, the ILC would be a 35-kilometre-long straight accelerator. While the LHC collides protons, which contain quarks and gluons, the ILC will smash electrons and positrons. Collisions will be "cleaner" than the LHC because electrons and positrons are fundamental particles. This makes for less ambiguity when trying to work out what produced any new particles. In the LHC, charged particles lose energy with each rotation.
Date of completion: 2020s
Cost: $8 billion
Pros: Cleaner collisions. Technology reliable and well understood
Cons: In some scenarios, the maximum energy may not be sufficient to see all new physics of interest
The Compact Linear Collider
The CLIC would be a positron and electron linear accelerator like the ILC - and is also yet to be approved - but it would be shorter and have collisions at higher energies. A high-intensity, low-energy drive beam runs parallel to the colliding beams. Power built up in the drive beam is transferred in quick bursts to the main beams.
Date of completion: 2020s
Cost: No official estimate, ~$10 billion
Pros: Cleaner collisions. High energy and compact - the ILC would need to be 140 kilometres long to achieve the same energy, so vastly more expensive. Greater sensitivity to massive particles compared with sLHC
Cons: R&D for the new technology is still at an early stage
Far in the future
Other proposals include the Very Large Hadron Collider, which would have a collision energy of 40 to 200 TeV and would have to be built from scratch. Muon colliders, and an LHeC - smashing an electron beam into a proton beam - are also being considered.
http://www.newscientist.com/article/mg20427354.900-future-colliders-beyond-the-lhc.html