In December, data suggested a particle six times heavier than Higgs
It would not be described by Standard Model of particle physics
More collisions started in April 2016, to collect more data
Experts expect confirmation or refutation of its existence ‘very soon’
CERN spokesman told MailOnline it is still likely to take weeks
The first signs of a particle heavier than the Higgs boson was seen at the Large Hadron Collider (LHC) back in December.
Unexplained by current models, its existence might lead to the discovery of a whole new set of particles and possibly even a fifth fundamental force.
The first results were not enough to confirm the particle exists, but now the new particle could be confirmed within the next few weeks.
Two of the detectors, ATLAS and CMS, were counting particle decays that ended up in two photons, and found a potential new particle. If it turns out to be real, and not a blip, this would be a huge discovery. Two high-energy photons whose energy, shown in red, was measured in the CMS is illustrated
In data produced last December at the LHC in Geneva, two separate measurements found what looked like a particle six time heavier than the Higgs boson.
If it turns out to be real, and not just a blip in the measurements, this would be a huge discovery.
‘We should have enough data by mid-July to either confirm the result or place serious doubt on its existence,’ Professor James Olsen, CMS physics coordinator and a physicist at Princeton, told MailOnline.
‘The CMS plan is to have an updated result using the 2016 data by the ICHEP conference in Chicago (starting Aug 3), although this timescale could be accelerated if the LHC outperforms expectations.’
According to Dr Michele Redi. a research scientist at INFN Florence, writing in Scientific American, the hints of the new particle might be confirmed ‘within just a few weeks, or possibly even within days.’
‘If the bump is real, we are about to start writing a whole new chapter in the history of fundamental physics,’ Dr Redi said.
‘It is impossible to imagine where this could lead.
‘We could know the answer very, very soon.’
‘The LHC is in good shape, therefore delivering collisions and new data to the experiments,’ a spokeman from CERN told MailOnline.
‘It is clear that the ATLAS and CMS collaborations plan to analyze these data in preparation for the big conference of the year – ICHEP 2016 Chicago – early August – so in case they have enough data and there is something new, it should be known by then or just before.
‘I would say it will still take a few weeks before we can provide an update about “the bump” as analyzing the data requires some careful work.’
‘It would be something completely beyond the Standard Model, and the tip of an iceberg of a large new set of particles,’ Professor John Ellis, theoretical physicist at Kings College London told MailOnline, ‘if it exists!’
Two of the detectors, ATLAS and CMS, were searching for new physics by counting particle decays that ended up in two photons.
Measuring photons is a good method for detecting new physics because photons are easy to detect and physicists know what to expect in terms of results from background events.
They both separately saw photons with a combined energy of 750 GeV.
When particles decay into photons, they release energy equivalent to their mass multiplied by the speed of light squared.
We’re all familiar with Einstein’s most famous equation, and this observation is it in action. This means the particle that produced these photons is an as yet unknown with this exact amount of energy in the form of its mass.
‘It weighs about 750 GeV, corresponding to about six times heavier than the Higgs boson, and almost 800 times heavier than the proton,’ said Ellis.
It was a similar ‘bump’ that gave the first hints to the Higgs boson.
But the difference now is that the existence of the Higgs boson had already been predicted.
This new particle, if it exists, has not been predicted by the Standard Model, so would open up physicists to a whole new unexplored world and could lead to the discovery of a new set of particles.
In December last year the two observations, in the ATLAS and CMS detectors, hinted at a new particle six times heavier than the Higgs boson. The LHC will start making more collisions next month, April 2016, and experts can expect confirmation or refutation in the summer
When particles decay into photons, they release energy equivalent to their mass multiplied by the speed of light squared. The measurements saw photons with a combined energy of 750 GeV, about six times heavier than the Higgs boson, something that has not been predicted by the current theory describing particle physics
The Standard Model claims everything in the universe is made from the most basic building blocks called fundamental particles, that are governed by four forces: gravity, electromagnetic, weak nuclear and strong nuclear.
The forces work over different ranges and have different strengths.
This new particle, if it exists, would not fit into the description given by the Standard Model and so would lead to a whole new area of particle physics for them to explore.
Some have suggested it might even lead to the discovery of a fifth fundamental force.
‘This is possible, but there must at least be a set of unknown particles to explain how this new particle decays, and probably how it is produced,’ said Ellis.
This development is exciting because the Standard Model has left some questions unanswered for years, so scientists are keen to break free of it and find new theories.
It can’t explain gravity, for example, because it is incompatible with our best explanation of how gravity works – general relativity, nor does it explain dark matter particles.
The quantum theory used to describe the small particles in the world, and the general theory of relativity used to describe the larger objects world, are also difficult to reconcile.
Nobody has managed to make the two mathematically compatible in the context of the Standard Model.
According to the Big Bang theory, matter and antimatter were created in equal amounts at the start of the universe and so they should have annihilated each other totally in the first second or so of the universe’s existence.
This means the cosmos should be full of light and little else.
But because it isn’t there must have been a subtle difference in the physics of matter and anti-matter that has left the universe with a surplus of matter and that makes up the stars we see, the planet we live on and ourselves.
The detectors saw photons with a combined energy of 750 GeV. When particles decay into photons they release energy equivalent to their mass multiplied by the speed of light squared. This means the particle that decayed into them would have been about six times heavier than the Higgs boson
But the observations seen so far are not enough to confirm the existence of a particle.
The CERN physicists need to make sure the observations were not just down to chance, so it comes down to collecting much more data and waiting to see if the particle is spotted again.
Some remain unconvinced.
‘Indeed, I don’t see yet statistically convincing bumps that would point to the existence of a new particle in the LHC data,’ Professor Patrick Janot, working on the CMS detector at CERN told MailOnline.
The LHC started making more collisions in April, and the results that might confirm or refute the existence of this particle could be available soon.
‘You will hear solid statements in summer,’ Professor Janot said back in March, ‘when a lot more data than in 2015 are accumulated at 13 TeV.’
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