Large Hadron Collider discovers new particle called the pentaquark

Large Hadron Collider discovers new particle called the pentaquark

Large Hadron Collider discovers new particle called the pentaquark

0 comments 📅15 July 2015, 02:18

A new particle called the pentaquark has been discovered by scientists at the Large Hadron Collider (LHC).

The previously unseen class of particle was first predicted to exist in the 1960s but has eluded physicists until now.

It was detected by Cern’s Large Hadron Collider beauty (LHCb) experiment at the LHC in Switzerland.

A new particle called the pentaquark has been discovered by scientists at the Large Hadron Collider (LHC). This illustration shows one possible layout of quarks in a pentaquark particle

A new particle called the pentaquark has been discovered by scientists at the Large Hadron Collider (LHC). This illustration shows one possible layout of quarks in a pentaquark particle

The LHCb experiment specialises in investigating the slight differences between matter and antimatter.

LHCb spokesperson Guy Wilkinson said: ‘The pentaquark is not just any new particle.

‘It represents a way to aggregate quarks, namely the fundamental constituents of ordinary protons and neutrons, in a pattern that has never been observed before in over fifty years of experimental searches.

‘Studying its properties may allow us to understand better how ordinary matter, the protons and neutrons from which we’re all made, is constituted.’

Back in 1964 American physicist, Murray Gell-Mann proposed the existence of sub-atomic particles called quarks. The work earned him the Nobel Prize in 1969.

He claimed that the properties of particles called baryons and mesons could be explained if they were made up of other even tinier particles – quarks.

He also theorised that there could be a particle called a pentaquark, made up of four quarks and an antiquark, which is the anti-matter equivalent of a quark, the BBC reported.

It has taken until now to prove his idea true.

The findings have been submitted to the journal Physical Review Letters.

To come to their conclusions, the international team of physicists studied the way in which an unstable sub-atomic particle called Lambda b decayed into three other particles.

They found that the production of the three particles sometimes involved intermediate states, which have been named Pc(4450)+ and Pc(4380)+.

LHCb physicist Tomasz Skwarnicki of Syracuse University in New York, said: ‘We have examined all possibilities for these signals and conclude that they can only be explained by pentaquark states.’

‘More precisely the states must be formed of two up quarks, one down quark, one charm quark and one anti-charm quark.’

Scientists got excited that the particle had been found earlier in the millennium, but sightings proved to be inconclusive because they measured mass distribution against background noise to look for a pentaquark’s signature.

The experts described the previous searches as looking for silhouettes in the dark, whereas LHCb conducted the search with the lights on.

Using the LHC allowed experts to look at data from four different perspectives, giving them a multi-dimensional view of the transformation of sub-atomic particles.

All these perspectives pointed to the same conclusion – the presence of pentaquarks.

Wilkinson told The Guardian: ‘One place where pentaquarks may be relevant is when stars collapse and form neutron stars, the final stage of collapse before some go on to make black holes.

‘In that environment, it’s quite possible that pentaquarks are formed, and if that’s so, it could have significant consequences for what happens to the stars, what they look like and what is their ultimate fate.’

The discovery comes just four months after the LHC shut down for repairs and upgrades for two years.

source: http://www.dailymail.co.uk