Scientists at CERN discover 3 exotic subatomic particles
What's the story
As scientists at CERN's Large Hadron Collider (LHC) continue to uncover the mysteries of the universe's formation, they have discovered three never-before-seen subatomic particles. The new "exotic particles" include a new kind of 'pentaquark' and the first-ever pair of 'tetraquarks.' The new discovery is by physicists who are part of the Large Hadron Collider beauty (LHCb) collaboration.
Context
Why does this story matter?
After three years of inactivity, the Large Hadron Collider is back at it again. Operating at an unprecedented energy of 13.6 trillion electronvolts, the collider offers prospects for new discoveries in particle physics. The discovery of new quarks is considered only the beginning as the collider begins its 'Run 3' or third round of collisions. We will certainly see more in the coming days.
Terminology
What are quarks?
Quarks are elementary particles that usually combine in groups of two or three to form hadrons like protons and neutrons. Rarely, however, they combine to form four quarks and five-quark particles, or tetraquarks and pentaquarks. Quarks are found in six flavors: up, down, charm, strange, top, and bottom. Scientists began observing quarks in experiments only in the last 20 years.
Discovery
The doubly-charged tetraquark was found along with its neutral partner
The latest discoveries include the pentaquark, the doubly-charged tetraquark, and its neutral partner. The former was found during an analysis of decays of negatively charged B-mesons. It is made up of charm quark, charm antiquark and up, down, and strange quarks. The tetraquark was found alongside its neutral counterpart in an analysis of decays of positively charged and neutral B mesons.
Information
Pentaquark discovered is the first with a strange quark
The pentaquark discovered is the first one to be found with a strange quark. The doubly-charged open-charm tetraquark is composed of a charm quark, a strange antiquark, an up quark, and a down antiquark.
Importance
The observation will help develop unified model of exotic hadrons
The new kind of pentaquark and the first duo of tetraquarks will provide a better understanding of the strong force that holds the nuclei of atoms together. "Finding new kinds of tetraquarks and pentaquarks and measuring their properties will help theorists develop a unified model of exotic hadrons, the exact nature of which is largely unknown," said Dr. Chris Parkes, spokesperson of LHCb Collaboration.