Scientists are looking for mysterious hidden particles which they believe could help answer some of our most burning questions about the universe.
The so-called “hidden sector particles” have so far evaded all previous attempts to observe them and line up very weakly, if at all, with the current theory of particle physics, known as the Standard Model.
The Search For Hidden Particles (SHiP) experiment, an international collaboration between 54 institutes over 18 countries, will see a proton beam used to hit a fixed target and produce a variety of particles – far more than current methods have been able to.
Scientists hope hidden particles will then be found in within the mix.
SHiP will have its own facility built by CERN, the European Organisation for Nuclear Research, from 2027, with the experiment set to begin collecting data as soon as 2030, CERN says.
The project’s approval, which comes 10 years after its first pitch, marks “a new era” in the search for hidden particles, according to its leader Professor Andrey Golutvin.
Prof Golutvin, from Imperial College London, said: “SHiP has the unique possibility to solve several of the major problems of Standard Model of particle physics and we have the prospect of discovering particles that have never been seen before.”
Why is the experiment happening?
CERN, located near Geneva in Switzerland, is already home to the world’s largest particle accelerator – the Large Hadron Collider (LHC).
The LHC, which started operating in 2008, discovered the so-called “God particle” – the Higgs boson – which enabled researchers to better understand where matter gets its mass from.
However, it has still been unable to find out more about the secrets of dark matter and dark energy – little known forces and particles that would allow scientists to have a better understanding of the universe.
And those undetected forces and particles make up around 95% of the universe.
CERN have already put forward proposals for a new £17bn “supercollider” called the Future Circular Collider (FCC) which it hopes will help it uncover those mysteries – but that isn’t set to be constructed until the 2040s.
The hope is the SHiP experiment, which is significantly cheaper, will help the LHC find some non-Standard Model particles while the wait for the FCC goes on.
Professor Golutvin said: “Hidden sector theories give us the prospect of solving problems of the Standard Model and as time has passed, and we have not observed new particles at the energy-frontier, the case for exploring this area has been getting stronger and stronger.”
What is it looking for specifically?
The SHiP experiment is designed to be very broad in its search, looking for a range of particles that only interact very weakly with regular matter, including potential dark matter.
Dark matter, which is unobservable from Earth, is thought to make up around 80% of matter in the universe – but it doesn’t seem to absorb or emit detectable radiation.
Its existence can be inferred from the way galaxies move – they stay together and those in clusters move faster than expected.
SHiP also hopes to find particles that could explain other mysteries of the Standard Model – such as why there currently exists much more regular matter than antimatter, known as the matter-antimatter asymmetry.
How will it work?
To simplify an incredibly complicated process: SHiP will use high-intensity proton beams to smash particles into a block of material, producing a variety of particles at a bigger volume than current experiments.
Imperial College London, which is leading the collaboration, explains: “When these particles decay or interact, they can produce the hidden particles SHiP is looking for.
“The energy and intensity of the SPS beam will enable huge numbers of well-known particles to be produced, meaning that SHiP will be able to make the world’s best searches for new hidden particles.”