A quantum property of the charm quark whose conservation explains the absence of certain strange-particle decay modes and that accounts for the longevity of the J particle.

分子量夸克粒子的一种量子属性，夸克粒子的存在说明了某些特别粒子腐蚀模式的缺乏，这也是J粒子存在时间长的原因。

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The old linear accelerator at Stanford was repurposed, turning it from the machine that co-discovered a particle known as the charm quark (thus winning its operators a Nobel prize) into a factory for making particles called B mesons.

ECONOMIST: The arrow of time