41. The Upsilon is a flavourless meson called a quarkonium. 42. Adapted from Meson Galicia, Norwalk, Conn. 43. Several other hypothetical " exotic " mesons lie outside the quark model of classification. 44. These interactions usually produce pi mesons initially, which most often decay to muons. 45. Each pion consists of a quark and an antiquark and is therefore a meson . 46. The other members of this octet are the four kaons and the eta meson . 47. Examples of mesons include the pion, kaon, and the J / ?. 48. Meson power is dangerous to use in atmosphere.49. By 1935 the nuclear force was conceived to be transmitted by particles called mesons . 50. CLEO decided to study the various bottom and charm quarkonia states and charm mesons .
