Cern discovers a boson, but not the Higgs

Scientists at the Cern physics research centre outside Geneva have made their first new particle discovery using the massive Large Hadron Collider (LHC) atom smasher.

The sub-atomic particle known as Chi-b (3P) was uncovered in the debris from colliding protons. The finding should help scientists better understand the forces that hold matter together.

The Chi-b(3P) comprises two relatively heavy particles, the beauty quark and its antiquark, which are bonded by the so-called “strong” force, which also causes the atomic nucleus to stick together, say researchers. Quarks are the building blocks of protons and neutrons, which in turn are the building blocks of atoms.

The Chi-b(3P) is a heavier version of a particle that was first observed around 25 years ago.

“People have thought this more excited state should exist for years but nobody has managed to see it until now,” Professor Roger Jones, who works on the Atlas detector at the LHC, told BBC News. 

“It’s also interesting for what it tells us about the forces that hold the quark and the anti-quark together – the strong nuclear force. And that’s the same force that holds, for instance, the atomic nucleus together with its protons and the neutrons.”

On December 13, physicists at Cern said they had narrowed the search for the Higgs boson – the so-called elusive sub-atomic, or “God particle”, which is said to be the missing link in the Standard Model of physics and may confer mass.

Cern oversees the $10 billion (SFr9.4 billion) LHC under the Swiss-French border, a 27-kilometre tunnel where high energy beams of protons are sent crashing into each other at incredible speeds.