European scientists discover two new subatomic particles
The discovery was made in an experiment at the Large Hadron Collider, subatomic particle accelerator
GENEVE, November 19. /TASS/. European Organization on Nuclear Research (CERN) scientists discovered two new subatomic particles in the baryon family. According to the CERN headquarters statement, the discovery was made in an experiment at the Large Hadron Collider (LHC), subatomic particles accelerator, situated in Switzerland and France.
According to the communique, these particles “were predicted to exist by the quark model but had never been seen before”. But another particle in the baryon family was discovered in 2012.
Like the protons that the LHC accelerates, the new particles are baryons made up of three quarks (fundamental particles) bound together by the strong force. The types of quarks are different, though. Thanks to one of them, the heavyweight b quark, they are more than six times as massive as the proton.
However the mass of the opened particles depends not only on total weight of quarks but also on their configuration. Because of different spin position (elementary particles angular momentum) in two lighter quarks the particles have different mass.
"Nature was kind and gave us two particles for the price of one," added Matthew Charles, of the CNRS's LPNHE laboratory at Paris VI University, in a statement. Ha said one of the particles “is very close in mass to the sum of its decay products: if it had been just a little lighter, we wouldn't have seen it at all using the decay signature that we were looking for”.
As well as their masses, scientists have also studied their stability. The results match predictions based on the Quantum Chromodynamics (QCD) theory – in theoretical physics describing the interaction of particles.
The measurements were based on data collected at the Large Hadron Collider during 2011-2012.
The LHC is currently being prepared to operate at higher energies when it restarts in the spring of 2015.