charm A quantum number that is equal to the number of charm quarks in a particle minus the number of anticharm quarks. Charm quarks were the fourth flavor (type) of quark to be discovered, in 1974. The lightest particles with charm are the D mesons, which are approximately twice as heavy as the proton. Related category PARTICLE PHYSICS Also on this site: Encyclopedia of Alternative Energy & Sustainable Living Encyclopedia of History Transport Concepts & Designs (partner site) |