Mesons are subatomic particles composed of one quark and one antiquark.
The importance of lighter mesons is that they are the associated quantum-field particles that transmit the nuclear force, in the same way that photons are the particles that transmit the electromagnetic force. However, such particles are regularly created in experiments, in order to understand the nature and types of the heavier types of quarks which compose the heavier mesons.
Mesons are composed of quarks, they participate in both the weak and strong interactions. Mesons with net electric charge also participate in the electromagnetic interaction.
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