The minimal standard model of quarks and leptons is extended with a set of vectorlike fermions to allow baryon number $B$ to become a gauged $U(1)_B$ symmetry. The $B$ assignments of the new particles are determined by renormalizable interactions with the known quarks through a color triplet scalar diquark. The spontaneous breaking of $U(1)_B$ by a scalar with $B=3$ results in a conserved residual global $B$ symmetry. A singlet neutral scalar with $B=2$ is a possible long-lived dark-matter candidate.

中文翻译：

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测量重子数和二重子暗物质

夸克和轻子的最小标准模型扩展了一组类似向量的费米子，以允许重子数 $B$ 成为测量的 $U(1)_B$ 对称性。新粒子的 $B$ 分配是由通过彩色三重标量双夸克与已知夸克的可重整化相互作用决定的。$U(1)_B$ 被$B=3$ 的标量自发破坏导致守恒的剩余全局$B$ 对称性。$B=2$ 的单重态中性标量可能是一种可能存在的长寿命暗物质候选者。