March 21, 2017

LHC discovers five new particles at the same time

Last week, the Large Hadron Collider beauty experiment (LHCb) reported finding a new system of five particles, all in a single analysis.

Finding just one new particle is an accomplishment by itself, but finding five new states all at once is simply remarkable.

"These particles have been hiding in plain sight for years, but it has taken the exquisite sensitivity of the LHCb to bring them to our attention,” Tara Shears, an LHCb team member from of Liverpool University told BBC News.

According to a published academic report, the particles discovered were the excited states, or states with energy above the ground state, of a particle known as "Omega-c-zero", Ωc0. According to standard convention, the particles were named Ωc(3000)0, Ωc(3050)0, Ωc(3066)0, Ωc(3090)0 and Ωc(3119)0.

The Omega-c-zero particle is baryon, which is in the same category of particles as the neutron and proton, but far more exotic. All of these particles are comprised of quarks, but the Omega-c particles are made of "Charm" and "Strange" quarks, heavier versions of the Up and Down quarks that neutrons and protons contain.

Discovering more about the universe

Since the discovery of the Omega-c particle, it was believed that there were heavier variations and now, physicists at the European Organization for Nuclear Research (CERN) have discovered them. CERN researchers said by investigating these heavier sibling particles, they'll learn more around the nuclear “strong” force, which holds atoms together.

The researchers at CERN behind the LHCb experiment said this discovery was achievable because of the specialized capabilities of the LHCb detector in the specific recognition of several kinds of particles and also as a result of the massive dataset accrued throughout the first and second runs of the Large Hadron Collider. These two factors permitted the five excited states to be discovered with a tremendous degree of statistical significance, meaning the discovery is not merely a statistical fluke of data.

The LHCb researchers said the next phase will be figuring out the quantum numbers of the new particles, which are unique numbers used to establish the properties of a particular particle. The team said they will also be figuring out the particles' theoretical significance. This discovery may lead to realizing how the three constituent quarks are held within a baryon. Finally, the team said they plan to probe the connection between quarks, which plays a crucial role in identifying multi-quark states, like tetraquarks and pentaquarks.


Image credit: LHCb Collaboration