As Futura explained in a previous articleresearchers from CERN collide with protons that they accelerate to gears increasingly close to that of the light for just over 60 years, with the commissioning on 24 November 1959 of CERN’s first large particle accelerator: the Proton Synchroton (PS).
At the time, the machine made it possible to produce protons whose energies reached 25 GeV, exceeding the hopes of the creators of the PS and making the instrument the most powerful particle accelerator in the world. The design of the machine was so brilliant that it still works today and serves as a pre-accelerator (there are several, as the video above explains) to the beams of the LHC. It was with it that CERN researchers discovered neutral currents and bosons intermediaries of the Glashow-Salam-Weinberg electroweak theory. Versatile, this synchrotron has been used both to accelerate electrons only light and heavy ions like those of theheliumof sulfurof the’indium and leadallowing you to explore the secrets of the quagma during the Big Bang.
A documentary on the discovery of W bosons, at CERN, in the early 1980s. These bosons are massive due to the supposed existence of the Brout-Englert-Higgs mechanism. Here are some of the keys to understanding how their discovery took place, keys that are still relevant to understanding those of the LHC today. It talks about the LEP, the electron-positron collider that occupied the LHC tunnel before it. © CERN
Collisions at 13.6 TeV this summer for Run 3
But, this Monday, April 25, 2022, the successors of the engineers and physicists responsible for the success of 1959 announce that they have broken a world record for the energy of protons accelerated in one of the last scientific and technological cathedrals of the noosphere with beams of protons reaching energies of 6.8 TeV, i.e. say 6,800 GeV!
They also announce that the first collisions with these beams in the detectors equipping the LHC should take place this summer, after the final adjustments and checks of the machine. We will therefore have at that time 13,600 GeV which could give as many new protons for each collision between two protons since in this unit of energy and because of the relation ofEinstein on equivalence mass energy, a proton has a mass of about 1 GeV. Many other particles are in fact generated with each collision and it is now hoped that by reaching the new threshold of 13.6 TeV of the particles of black matter which would be so heavy will finally be created, even perhaps, but it has become much less probable, mini quantum black holes and other effect of thespace-time foam.
Let’s hope that the third LHC data collection campaign, Run 3, which will start soon and will last a few years, will be full of surprises.
The LHC record on April 25, 2022. To obtain a fairly accurate French translation, click on the white rectangle at the bottom right. The English subtitles should then appear. Then click on the nut to the right of the rectangle, then on “Subtitles” and finally on “Translate automatically”. Choose “French”. © CERN
The LHC emerges from 3 years of slumber to hunt for new physics
Article of Laurent Sacco published on 04/25/2022
The Large Collider hadrons, the LHC, is again circulating protons in its 27 kilometer circumference ring. There are still tests and fine-tuning to be done, especially with the detectors, but in a few months the hunt for new particles and new physics that may help solve the puzzles of matter and dark energy will restart.
In a few months, we will be able to celebrate the 10th anniversary, on July 4, 2022, of the announcement of the discovery of the Brout-Englert-Higgs boson with the LHC, crowning the work more than 50 years ago of a handful of Nobel Prize in Physics, some of whom are now deceased, such as Steven Weinberg and Murray Gell Mannand others very much alive, like Francois Englert.
Admittedly, much more was expected of the LHC, such as the creation of black mini holes and dark matter particles. It hasn’t happened and all hope is not lost on that yet. More generally, new physics can still manifest itself there indirectly and this may already be the case with the last determination of the mass of the W boson, as physicists announced very recently..
The world’s largest and most powerful particle accelerator has restarted after a hiatus of more than three years for maintenance, consolidation and upgrades. On April 22, at 12:16 p.m., two proton beams circled the 27-kilometre ring of the Large Hadron Collider in opposite directions, at their injection energy of 450 billion electron volts (450 GeV). To obtain a fairly accurate French translation, click on the white rectangle at the bottom right. The English subtitles should then appear. Then click on the nut to the right of the rectangle, then on “Subtitles” and finally on “Translate automatically”. Choose “French”. © CERN
Protons at 450 GeV, but no collision yet
But for that, new collisions of protons are needed in the giant detectors along the 27 kilometer ring of the Large Hadron Collider. However, CERN has just announced that after a pause of several years devoted to work to improve the LHC accelerators and detectors, the circulation of proton beams had resumed, even if it is not yet question of taking new data to track new particles.
This just happened on April 22, at 12:16 p.m. CEST, with two proton beams circulating in opposite directions along the ring, the injection energy already being 450 billion electronvolts (450 GeV ) per particle in these beams, which in theory makes it possible to create for example approximately 900 protons for each collision between two particles (the mass of a proton is approximately 1 GeV, according to the units expressing the Einstein relation between energy and mass).
A partial version of the previous video directly in French. © CERN 2022
” These beams traveled at injection energy and contained a relatively small number of protons. The high-intensity, high-energy collisions will occur in a few months, but these first beams mark a successful restart of the accelerator after the intense work carried out during the long shutdown commented on this event Rhodri Jones, Head of the Beams Department at CERN.
” Machinery and equipment underwent significant upgrades during CERN’s second long shutdown of the accelerator complex”, the LHC itself has undergone an extensive consolidation program and will now operate at even higher energy. Thanks to major improvements to the injector complex, it will provide much more data to upgraded LHC experiments », Explains, meanwhile, in a press release from Cern Mike Lamont, director of accelerators and technology of the European laboratory.
For the record, a presentation of CERN. © CERN
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