Didymos Thomas;24993 wrote:
Well, we're still alive.
Yes, but they haven't even got the thing up to full speed yet. It hasn't even accelerated particles faster than Fermilab's Tevatron at this point. (The Tevatron is a particle accelerator in Illinois, USA that is currently the world's highest energy atom smasher.) The Tevatron accelerates particles to 980 GeV
(giga elevtron volts) and crashes them head on, for a total energy of 1960 GeV
. So far the LHC has only gone up to about 500 GeV
or so, and they haven't done any collisions yet. In a couple of weeks however, the LHC should be smashing protons into each other with a total collision energy of 10,000 GeV
. And then in the spring I heard they're supposed to get it up to a collision energy of 14,000 GeV
. So if we're to get killed by what the LHC is doing it will still probably be a couple of weeks before it happens. Of course, we're not supposed to get killed, the physicists say.
Didymos Thomas;24993 wrote:
Expensive, but interesting invention. I'm happy to see it up and running. Hope we learn something for our billions of dollars in investment.
I was looking at an article yesterday about some of the advances that have come from this kind of research. Here's some highlights:
In 1897 J.J. Thomson discovered the electron, using a kind of particle accelerator, a cathode ray tube, that accelerated a beam of negatively charged particles between electrical terminals and made a phosphorescent green glow around the positive terminal. (Wilhelm Roentgen had used this same device in 1895 in his discovery of the particle beams that gave us x-ray technology.) Cathode ray tubes using this same principle of particle acceleration now sit in television sets in hundreds of millions of American homes, and illuminate the screens of millions of computers and scientific and medical instruments.
In 1909, students in the laboratory of physicist Ernest Rutherford directed alpha particles from a lump of decaying radium at sheets of gold foil. The unexpected way the particles scattered when they hit the foil led Rutherford to the discovery of the atomic nucleus in 1911. Rutherford's discovery was a scientific leap forward. However, no one, least of all Rutherford himself, foresaw the enormous consequences it would have. Rutherford is reported to have said, "Anyone who expects a source of power from the transformation of these atoms is talking moonshine." He made his statement five years before the first demonstration of nuclear fission. Rutherford's words have an ironic ring in a world transformed by nuclear energy.
In the 1920s, increasing data from experimental discoveries about the nature of the atom led to the theory of the structure and behavior of atoms we call quantum mechanics, and to an utterly new understanding of nature. From this new knowledge came lasers and solar cells and, in 1947, the discovery of the transistor, the basis of all modern electronics and the age of information.
Synchrotron radiation has become an indispensable tool for thousands of researchers in such fields as materials science and engineering, surface chemistry, biotechnology, medical imaging and environmental science.
Fermilab - The benefits of high-energy physics research
In the 1930s, Lawrence often kept the cyclotron in Berkeley running all night in order to produce enough radioisotopes for California hospitals to use in treating cancer. He began a tradition of using accelerators for medical diagnosis and treatment. Today, patients receive cancer treatment using beams of neutrons produced by accelerators whose main job is to produce protons for physics research. In another therapeutic approach, doctors at Loma Linda University Medical Center now treat over 100 cancer patients each day with protons from a synchrotron designed and built at Fermi National Accelerator Laboratory. Medical facilities around the world are investigating this technology. Linear electron accelerators in thousands of hospitals around the world treat millions of cancer patients every year.
Computer-aided tomography, the CAT scan, perhaps the most significant advance in medical radiography since the 1895 discovery of x-rays, originated in particle detection methods developed by high-energy physicists. The underlying magnet technology for Magnetic Resonance Imaging (MRI) came from particle physics research. Positron Emission Tomography (the PET scan) uses crystals of a material developed for high-energy physics particle detectors.
They released the week 1 progress report for the LHC yesterday.
CERN | LHC First Beam - Final LHC Synchronisation Test a Success
Geneva, 18 September 2008. After a spectacular start on 10 September, the LHC enjoyed a mixed first week of commissioning with beam. To get beams around the ring in both directions on the first day exceeded all expectations, and the success continued through the night, with several hundred orbits being achieved.
The next step in the commissioning process is to bring in the radio-frequency (RF) system that keeps the beams bunched, rather than spreading out around the ring, and will eventually accelerate them to 7 TeV. The RF system works by 'capturing' the beam, speeding up the slower moving particles and slowing down the faster ones so that the beam remains bunched into fine threads about 11 cm long. Without it, the beam quickly dissipates and cannot be used for physics.
On Thursday night, 11 September, beam two, the anti-clockwise beam, was captured and circulated for over half an hour before being safely extracted from the LHC. The next step is to repeat the process for beam one, and that is set to begin this week.
The intervening time has been spent recovering cryogenic conditions after the failure of a power transformer on one of the surface points of the LHC switched off the main compressors of the cryogenics for two sectors of the machine. The transformer, weighing 30 tonnes and with a rating of 12 MVA, was exchanged over the weekend. During this process, the cryogenics system was put into a standby mode with the two sectors kept at around 4.5 K. Since the beginning of the week the cryogenics team have been busy re-cooling the magnets and preparing for operation with beam, which is currently forecast for today. The next stage of the commissioning will be single turn studies using beam one, followed by RF capture and circulating beam in both rings.
The LHC is on course for first collisions in a matter of weeks. Next update 24 September at the latest.
And there are some of their detector images from the beam here - CMS - Breaking News
Such as this one: