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The collaboration has observed a new kind of “pentaquark” and the first-ever pair of “tetraquarks” The international LHCb collaboration at the Large Hadron Collider (LHC) has observed three never-before-seen particles: a new kind of “pentaquark” and the first-ever pair of “tetraquarks”, which includes a new type of tetraquark. The findings, presented today at a CERN seminar, add three new exotic members to the growing list of new hadrons found at the LHC. They will help physicists better understand how quarks bind together into these composite particles. Quarks are elementary particles and come in six flavours: up, down, charm, strange, top...

New York, March 3 : A team of US researchers has detected a new form of elementary particle called the "four-flavoured" tetraquark that can affect scientists' understanding of "quark matter" -- the hot, dense material that existed moments after the Big Bang and may still exist in the super-dense interior of neutron stars. For most of the history of quarks, it's seemed that all particles were made of either a quark and an antiquark or three quarks, "This new particle is unique -- a strange, charged beauty. It's the birth of a new paradigm. Particles made of four quarks --...

All tetraquarks and pentaquarks that have been discovered so far contain two charm quarks, which are relatively heavy, and two or three light quarks – up, down or strange. This particular configuration is indeed the easiest to discover in experiments. But the latest tetraquark discovered by LHCb, which has been dubbed X(6900), is composed of four charm quarks. Produced in high-energy proton collisions at the Large Hadron Collider, the new tetraquark was observed via its decay into pairs of well-known particles called J/psi mesons, each made of a charm quark and a charm antiquark. This makes it particularly interesting as...

The newly-discovered particles, named Σb(6097)+ and Σb(6097)-, are predicted by the quark model, and belong to the same family of particles as the protons that the Large Hadron Collider (LHC) accelerates and collides: baryons, which are made up of three quarks. But the type of quarks they contain are different: whereas protons contain two up quarks and one down quark, the new particles are bottom baryons composed of one bottom quark and two up quarks or one bottom quark and two down quarks respectively.The LHCb researchers found these particles using the classic particle-hunting technique of looking for an excess of...