B-meson, as the abbreviation suggests, is any meson that contains a bottom (or an antibottom) quark.

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When a meson and an anti-meson of any description are created in a particle accelerator, they normally fly off in opposite directions.

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When a D0-meson decays, it produces daughter particles called pions and kaons.

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B-meson travelled before it broke down, and thus how long it lasted.

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The first example was a type of meson called a kaon.

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"The Argentine kicker, Santiago Meson, hit the upright with three of his four penalties, so things just didn't go well for the Pumas that day, " said Johnstone.

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They are looking in particular at how long it takes a B-meson to change its nature, focusing on one particular member of the extended B-meson family, the electrically neutral B0.

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Other experiments had seen some evidence of the D-meson's flipping, but this is the first that crosses the "five sigma" level of statistical significance that particle physicists use to denote an official discovery.

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