Large Hadron Collider scientists seek dark matter

19 April 2013
By Sofia Mitra-Thakur
Mobile version
Share |
The LHC (Large Hadron Collider) tunnel

The LHC (Large Hadron Collider) tunnel

After finding a species of the Higgs boson, CERN scientists are now seeking dark matter at the Large Hadron Collider (LHC).

A race is on between groups at the LHC, the world's biggest particle accelerator, and other scientists operating in space and deep underground who are chasing the same discovery.

Dark matter is invisible "stuff" that holds galaxies together with gravitational glue but defies common sense by being undetectable by any direct means.

It is thought to make up around a quarter of the mass-energy in the universe.

Finding it would be a major coup second only to detecting the Higgs boson, the elementary particle believed to be responsible for mass.

It will be a top priority when a revamped and almost twice as powerful LHC is switched back on in March 2015 after a two-year shut down and refit.

The £2.6 billion machine fills a 27 kilometre (17 mile) circular underground tunnel that straddles the border of France and Switzerland near Geneva.

Protons - the hearts of atoms - fired in opposite directions around the tunnel at just under the speed of light are smashed together at enormous energies, simulating conditions that occurred an instant after the Big Bang.

Scientists hope to create new particles out of the fire balls at four detector points placed around the LHC ring.

Before the shut down, the LHC reached a record-breaking energy level of eight trillion electrovolts (8 Tev). After the upgrade, this will be boosted to 14 Tev.

As energy is converted to matter, higher energies allow heavier and more exotic particles to be created.

One of them could turn out to be a weakly interacting massive particle, or Wimp - the leading candidate for dark matter.

Dr David Newbold, from the University of Bristol, a member of the CMS (Compact Muon Solenoid) detector experiment at the LHC, said: "There's a real conflict between astronomy, which says dark matter is there, and particle physics, which hasn't found anything yet.

"This has been the big surprise, Nature's failure to put dark matter in a place where we can find it."

The pressure is on the LHC scientists after possible signs of dark matter emerged from a laboratory buried 2,600 feet underground in an American mine.

Researchers from the Cryogenic Dark Matter Search (CDMS) in Minnesota are trying to detect dark matter particles clashing with the nuclei of normal Earthly atoms.

Earlier this week they reported three signals that could indicate Wimp particle collisions, but the evidence is a long way from being confirmed. 

One puzzle is that the data suggest Wimps are much lighter than had been thought, in which case they should already have been produced at the LHC or another accelerator facility.

Earlier this month, a team operating a £1.32 billion particle detector attached to the International Space Station announced that it had found a potential "smoking gun" of dark matter.

The Alpha Magnetic Spectrometer (AMS) spotted positrons - antimatter electrons - that could have been emitted by Wimp particle collisions far away in space.

"There's a bit of a race on," said Dr Newbold, speaking at CERN, the European Centre for Nuclear Research where the LHC is located.

"It's possible that we could see a direct signature of dark matter from one of these experiments before you see it in the LHC. 

"But the CDMS result isn't conclusive and the AMS needs more data."

Colleague Professor Jon Butterworth, from University College London, who works on the giant Atlas detector, said: "When we go up in energy from 8 Tev to 14 Tev I'd say there's a 50/50 chance of finding dark matter. There's a slim chance that dark matter might be hiding in the data we've got now.

"I think dark matter is the most important thing as far as my experiment is concerned.

"People are very excited about this, and have been for a while. 

"We are on the edges of knowledge here and the nature of dark matter is a big question. I hope we'll be able to answer it in the next few years."

Dark matter is closely tied up with the concept of supersymmetry, an extension of the Standard Model theory that explains the functions of elementary particles.

Supersymmetry proposes that every known particle should have a heavier twin. Many scientists believe dark matter consists of these supersymmetry partners, and are hoping to be proved right.

However, finding such a particle would just be the beginning.

"We're talking about the simplest kind of supersymmetry," said Dr Newbold.

"There are theories that conjure up the possibility of multiple dark matter particles.

"The properties of dark matter, how many kinds of dark matter there are - all this is science yet to come."

Dark matter is now believed to make up around 26 per cent of the universe and "normal" matter just 4 per cent.

Dark energy - a mysterious force causing galaxies to hurtle apart at accelerating speed - is thought to account for the remaining 70 per cent.

Latest Issue

E&T cover image 1607

"As the dust settles after the referendum result, we consider what happens next. We also look forward to an international summer of sport."

E&T jobs

  • Digital Forensic Specialist (Audio)

    Met Police
    • London
    • Circa £37,305 plus £3,406 location allowance

    You’ll contribute to a wide range of research and development activities.

    • Recruiter: Met Police

    Apply for this job

  • MetOp-SG Receiver Project Manager

    Science and Technology Facilities Council (STFC)
    • STFC Rutherford Appleton Laboratory, Harwell, Oxfordshire
    • £37,213 - £50,926 (depending on experience)

    Project Manager to oversee the development, production and test of spaceflight components and integrated receiver systems

    • Recruiter: Science and Technology Facilities Council (STFC)

    Apply for this job

  • Systems Engineer

    Reaction Engines Ltd
    • Abingdon, Oxfordshire
    • Competitive + Benefits

    Perform general systems engineering tasks as necessary with specific focus on electronic systems and instrumentation.

    • Recruiter: Reaction Engines Ltd

    Apply for this job

  • Production Manager

    Reaction Engines Ltd
    • Abingdon, Oxfordshire
    • Competitive + Benefits

    An amazing opportunity to plan, direct and coordinate all manufacturing operations and activities in line with company strategy and business plan.

    • Recruiter: Reaction Engines Ltd

    Apply for this job

  • Navigation Sensors Principle Engineer

    MBDA
    • Stevenage
    • Competitive Salary & Benefits

    What?s the opportunity? An exciting opportunity has arisen in a rapidly evolving international team with increasing capabilities.  The Navigation Sensors Group is responsible for the...

    • Recruiter: MBDA

    Apply for this job

  • Technology Manager - External Communications

    BAE Systems
    • Frimley, England, Surrey
    • Negotiable

    Technology Manager - External Communications Would you like Lead the technical delivery of the External Communications System (ECS) capability sustainment & evolution projects within the common ECS (cECS) Baseline Design Management (BDM) programme? Th

    • Recruiter: BAE Systems

    Apply for this job

  • Graduate Process Engineer

    EFFECT Photonics
    • Brixham, Devon
    • £20,000 to £25,000

    Join our exciting journey to deliver new standards in the availability of data bandwidth.

    • Recruiter: EFFECT Photonics

    Apply for this job

  • Senior Principal Materials Engineer

    MBDA
    • Stevenage
    • Competitive salary & benefits

    What?s the opportunity? A fantastic opportunity has arisen for an experienced materials engineer/scientist specialising in non-metallic materials and processing. You will be given responsibility for...

    • Recruiter: MBDA

    Apply for this job

  • Postdoctoral Research Associate

    The University of Liverpool
    • Liverpool, Merseyside
    • £32,600 - £37,768 pa

    Applications are invited for a Postdoctoral Research Associate in a brand new area of communications.

    • Recruiter: The University of Liverpool

    Apply for this job

  • Test Engineering Opportunities

    HMGCC
    • Hanslope Park, Milton Keynes
    • Salary offered will depend on skills and experience

    Push incredible innovations beyond their limits. Opportunities for Software, Hardware, EMC, Test and Inspection Engineers!

    • Recruiter: HMGCC

    Apply for this job

More jobs ▶

Subscribe

Choose the way you would like to access the latest news and developments in your field.

Subscribe to E&T