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出典:『Wikipedia』 (2011/04/23 05:13 UTC 版)

英語による解説

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The bottom quark, also known as the beauty quark, is a third-generation quark with a charge of −¹⁄₃ e. Although all quarks are described in a similar way by the quantum chromodynamics, the bottom quark's large bare mass (around 4,200 MeV/c2, a bit more than four times the mass of a proton), combined with low values of the CKM matrix elements V_ub and V_cb, gives it a distinctive signature that makes it relatively easy to identify experimentally (using a technique called B-tagging). Because three generations of quark are required for CP violation (see CKM matrix), mesons containing the bottom quark are the easiest particles to use to investigate the phenomenon; such experiments are being performed at the BaBar and Belle experiments. The bottom quark is also notable because it is a product in almost all top quark decays, and would be a frequent decay product for the hypothetical Higgs boson if it is sufficiently light.