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Scientists can not take pictures of the Higgs boson. But they can find proof of its existence by watching "E = mc2" play in hundreds of millions of particle collisions per second and detect how it decays into other particles that they know how to spot .
Now, six years after the official discovery of the Higgs boson, particle physicists announce that they have spotted the Higgs in another way.
This announcement is not a surprise. It corresponds to the predictions of the standard model of particle physics, the plan of the universe both solid rock and probably incomplete on smaller scales.
But the news is certainly important; one could say that it closes the first chapter of the history of the Higgs boson, and offers a potential window for exploring some of the most troubling issues in the universe.
"This is the first time we see the coupling of Higgs to quarks." John Huth, a particle physicist at Harvard University who is working on the ATLAS collaboration at CERN in Switzerland, said Gizmodo .
"We thought that would happen, but until we saw it, we would not know for sure that it was coupled in this way to the quarks."
Fifty years ago, a team of scientists, including Peter Higgs, theorized the existence of the Higgs boson.The theoretical particle would explain why some particles that should be mbadless actually have a mbad, and potentially why all the fundamental particles have a mbad.
A billion-dollar search uncovered a particle that was very similar to the Higgs boson, which scientists at the Large Hadron Collider ATLAS and CMS experiments announced on 4 July 2012.
spotted the Higgs candidate by slamming protons and observing what came out. They compared these results to simulations of the appearance of the resulting collisions if the new particle did not exist.
About 30% of the Higgs bosons produced in these collisions should produce either a set of photons or a set of W and Z bosons, the particles that carry the weak nuclear force (one of the four fundamental forces) . But nearly 60 percent of the Higgs bosons are expected to disintegrate into a pair of bottom quarks – the second heavier of the six quarks.
All available evidence clearly shows that the new particle was actually the Higgs boson. , but locating the Higgs through the decay of the bottom quark was much more difficult than finding it via photons or the W and Z bosons.
The photons are evident in the detectors, and Ws and Z themselves disintegrate in pairs of muons or electrons, also easy to understand and detect, Sarah Charley writes for Symmetry Magazine . But the lower quarks seem much more messy in the detector, and it's easy to confuse the bottom quark pairs that come from the Higgs bosons with those produced in other ways.
The ATLAS collaboration finally claimed to have seen enough collisions of protons and background quarks to justify the announcement of the discovery at the 2018 International Conference on High Energy Physics (ICHEP) in Seoul, in South Korea.
You might remember the expression "standard deviations", or "sigmas", a threshold that physicists use to determine how unlikely it is that their measurement occurred by chance if their hypothesis was wrong . The reference particle physicists use five sigma to say that, after taking a lot of data, it is unlikely that anything happened by chance that they made a discovery.
Physicists obtained their five-sigma observation, a conclusion consistent with the predictions of the standard model
Physicists from the other experiment of the Higgs hunters, CMS, have noted the difficulty of Discovery. "ATLAS had to combine all the data the LHC had never collected since 2011 … and even then, sophisticated stuff like deep artificial neural networks and other mechanical learning was needed," said physicist Freya Blekman. the Vrije Universiteit Brussel. Gizmodo . CMS will soon publish similar results on the discovery.
Huth was excited by the result for existential reasons. On the one hand, the Higgs boson offers a way for particles to get their mbad through a kind of physical field that permeates the universe. On the other hand, the force acting between the mbades, the gravity, does not seem to enter the same quantum theory that describes the Higgs boson and the paradigm just after the Big Bang, in which the weak and electromagnetic nuclear force the force was united.
One way to better solve this problem might be to understand the strange field that accompanies the Higgs. This requires learning how the Higgs interacts with itself, a behavior that could be examined by examining the four queues of the bottom resulting from such interaction.
"We are at an interesting time when we need more information to help fill this puzzle," said Huth.
Huth thought the discovery was rock solid, but he pointed out that it required a lot of maths and variables to get the discovery of five sigma – there's always the concern that the computer is doing something stupid, but they did a lot of cross checking.
Another physicist of the CMS collaboration, André David, tempers the excitement, saying Gizmodo that Higgs bosons disintegrating into background quarks is the prediction of the Standard Model – this is 39, is the null result. Nothing strange has yet been learned. But he was excited at the idea that the results could better explain how quarks get their mbad because it is a way to measure the interaction between quarks and the Higgs boson.
This discovery is yet another tool for probing the deepest foundations of the Universe. But there is so much more to learn and, therefore, more observations to make. Said Huth: "You just have to continue to flake it out."
[ATLAS]
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