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:''This list is of all known and predicted scalar, pseudoscalar and vector mesons. See list of particles for a more detailed list of particles found in particle physics.'' Mesons are unstable subatomic particles composed of one quark and one antiquark. They are part of the hadron particle family – particles made of quarks. The other members of the hadron family are the baryons – subatomic particles composed of three quarks. The main difference between mesons and baryons is that mesons have integer spin (thus are bosons) while baryons are fermions (half-integer spin). Because mesons are bosons, the Pauli exclusion principle does not apply to them. Because of this, they can act as force mediating particles on short distances, and thus play a part in processes such as the nuclear interaction. Since 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. They are classified according to their quark content, total angular momentum, parity, and various other properties such as C-parity and G-parity. While no meson is stable, those of lower mass are nonetheless more stable than the most massive mesons, and are easier to observe and study in particle accelerators or in cosmic ray experiments. They are also typically less massive than baryons, meaning that they are more easily produced in experiments, and will exhibit higher-energy phenomena sooner than baryons would. For example, the charm quark was first seen in the J/Psi meson () in 1974,〔J.J. Aubert ''et al.'' (1974)〕〔J.E. Augustin ''et al.'' (1974)〕 and the bottom quark in the upsilon meson () in 1977.〔S.W. Herb ''et al.'' (1977)〕 Each meson has a corresponding antiparticle (antimeson) where quarks are replaced by their corresponding antiquarks and vice versa. For example, a positive pion () is made of one up quark and one down antiquark; and its corresponding antiparticle, the negative pion (), is made of one up antiquark and one down quark. Some experiments show the evidence of ''tetraquarks'' – "exotic" mesons made of two quarks and two antiquarks, but the particle physics community as a whole does not view their existence as likely, although still possible.〔C. Amsler ''et al.'' (2008): (Charmonium States )〕 The symbols encountered in these lists are: I (''isospin''), J (''total angular momentum''), P (''parity''), C (''C-parity''), G (''G-parity''), u (''up quark''), d (''down quark''), s (''strange quark''), c (''charm quark''), b (''bottom quark''), Q (''charge''), B (''baryon number''), S (''strangeness''), C (''charm''), and B′ (''bottomness''), as well as a wide array of subatomic particles (hover for name). ==Summary table== Because this table was initially derived from published results and many of those results were preliminary, as many as 64 of the mesons in the following table may not exist or have the wrong mass or quantum numbers. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「List of mesons」の詳細全文を読む スポンサード リンク
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